Joseph Henry's Record of Experiments Book 3

ID: SIA2012-6592 through SIA2012-6786

Creator: Henry, Joseph 1797-1878

Form/Genre: Paper

Date: 1842-1863

Citation: Smithsonian Institution Archives, Record Unit 7001, Box 21A, Folder: 3

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Summary

Record of Experiments book 3. Joseph Henry kept this record beginning with his tenure as a professor of natural philosophy, or physics, at Princeton University, and continued recording experiments after he became the first Secretary of the Smithsonian Institution in 1846. The book includes notes on his experiments dealing with electromagnetism and other scientific topics.

Subject

Princeton University

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Historic Images of the Smithsonian

Notes

See SIA2013-07399 through SIA2013-07575 for Henry's Record of Experiments Book 1 and SIA2013-07399 through SIA2013-07575 for Henry's Record of Experiments Book 2.

Contained within

Smithsonian Institution Archives, Record Unit 7001, Box 21A, Folder: 3

Contact information

Institutional History Division, Smithsonian Archives, 600 Maryland Avenue, SW, Washington, D.C. 20024-2520, SIHistory@si.edu

Date

1842-1863

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Topic

  • Secretaries
  • Science
  • Electromagnets
  • Experiments
  • Records
  • Physics
  • Electromagnetism

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  • Paper
  • Book

ID Number

SIA2012-6592 through SIA2012-6786

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Number of Images: 195 ; Color: Color ; Size: 18.35w x 13.53h ; Type of Image: Book ; Medium: Paper

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[[Front cover]] (III.)
[[blank page]] [[end page]] [[start page]] Note Book of Experiments by J Hentry Princeton N.Y.
[[term.?]] Aug. 21 st '94 [[end page]] [[start page]] 1 Oct 5th 1842 [[vertical line]] Phenomenon of a drop of water on heated metal Made to day a few experiments on the slow evaporation of water from the surface of heated metal. 1. Supported a silver spoon over a [[torch?]] lamp with a larger wick. Then after the metal was heatedpoured in water from a pipe, until [[strikethrough]] the [[?]] [[/strikethrough]] the spoon was nearly, or quite half full. The water was considerably aggitated,but remained without boiling and very slowly evaporated. 2. Made the same experiment with alcohol, the effect was produced as a lower temperature than with water,— also reheated the same with eather. 3. ^[[See page 222, this book]] Placed a quantity of [[?]] filings in the spoon, these were much agitated, and gathered up with the drop of water, and then floated, as it were, at some distance from the metal until the whole of the liquid was evaporated. It appears evident from the experiment, that the water is not in contact with the surface of the metal. Then is [??] [??] attraction of cohesion between the water and the metal, or if any, it is very small, for when a stick or [piece?] of wine is thrust into the drop, the water adheres to the wine on stick. 4. ^[[See page 222 of this book]] A piece of this metal ([filale?]) was thrown into the drop. The metal remained suspended, and moved with the gliding motion of the drop showing, as is the case of the filings, that the drop is not in close approximation with the surface of the metal. 5.Next tried mercury on a slip of platinum
9 October 5th 1842 [[vertical line-wavy]] Drop of water on heated metal---------, found that the same phenomenon was produced, the platinum was heated to [[strikeover]] [??]] [[/strikeover]] a white heat nearly. The globule remained a few moments staling, or in motion with the gliding motion of the drop of water, and then suddenly disappeared with something like an explosive action. 6. Tried on the same piece of platinum small globules of melted lead and tin, but no effect like that produced by the mercury and water was observed. The substance was incapable of giving off a vapour. 7 Small drops of water were thrown on to a small cup formed of thin plate platinum, heated to whiteness in the spirit lamp. The water remained some minutes un evaporated, slowly however diminishing in bulk, and when it got to the size of about that of a pin's head, it disappeared at once with a kind of an explosion & sometimes an explosion took place which seperated the small dish into two parts. _ all the time ^[[the]] drop was diminishing, the little cup of platinum which contained it, was at a low red heat, but the moment that the drop disappeared, the metal became white hot. This shows the constant evaporation which is going on. 8 When a drop of water ^[[is]] taken up on the end of a rod of bad conducting matter (for heat), and then held in the midst of the [[end page]] [[start page]] Oct 5th 1842 [[vertical line-wavy]]Drop of water on heated metal [[margin-upper right hand corner]] B [[/margin]] flame of a spirit lamp, the drop does not instantaneously disappear, but it remains several minutes and gradually disappears. It would appear from these experiments, that the slow evaporation of a drop of water on heated metal is due to the [[underlined]] constant[[/underlined]] generation as the lower surface of the drop of a quantity of steam, which by its elastic force, prevents the drop from coming [[black crossed out]] in contact with the heated metal. The heat necessary for the constant production of the steam, is conveyed to the water by eradiation from the heated metal. [[horizontal line-wavy]] Also it would appear that in order to the sudden evaporation which produces the phenomenon called boiling, it appears necessary that the water should be in physical contact with the metal, and if this be correct, boiling will not take place at the same temperature in vessels which are not capable of being infilmed with the liquid. Hence, I should infer that mercury will boil in a vessel of which the inner surface is amalgamated ^[[sooner]] than in one of glass, which has no attraction or little, for the metal. [[strikeover]] 8 [[/strikeover]] [[pencil]] 9 [[/pencil]] Could not produce the same effect with a glass plate. This substance appears to be [[page end]]
4 1842 Oct 6th } Water on heated metal so bad a conductor of heat, that the upper surface on which the drop is thrown, almost instantly cools, and lets the water down to the glass. The sudden evaporation then takes place. Put the drop upon a piece of [[??**]] platen [[**??]] into which a hole [[overstrike**]] of [[**end overstrike]] was made of about the 1/20 of an inch in diameter. Placed this over the lamp, and when the heat was up to that of redness, a drop of water would not pass through until the diameter was so much reduced, as to be less than that of the hole; it then fell through as if it had been a piece of lead. If a large ladle be heated red hot, and water poured cautiously into it, the liquid will not pass through holes of 1/10 of an inch in diameter. The cause of this is evident, the cohesion of the water remains nearly as strong as before the heating, while the stratus of steam prevents the water from [[circled**]] wetting [[**end circled]] wetting or infilming the iron. [[end page]] [[NEW PAGE]] 5 Oct. 6th 1842 } Arrangement of Long wire from Phil Hall to my study I made an arrangement a few days since of a long wire, extending from the electriccal machine in the Philos. Hall, to my study on the opposite side of the campus. The wire passed diagonally across the large lecture room to the south west window facing the Library, and thence to the southern most window of the two upper ones of the East end of the old college, then through the long upper college hall to the [[overstrike**]] window [[**end overstrike]] southerly window of the west end of the college, to the door of my study.The whole length of this wire is feet. It is supported by silk ribbons fastened to the side of the windows. This morning I completed a connect with this wire and the ground, by plunging the end next my study into the well, or rather by connecting it with the wire which is already in the well for the experiments on atmosphere elect., (see last book), and by placing the end of a copper wire with a plate of lead on it into Mr. Clow's well, and then connecting this last with the wire first mentioned. Whence small galvanometer of fine wire was placed in the circuit in my study and a small [[overstrike**]] galvano [[**end overstrike]] electromotor, consisting of a plate of Lead of about a tenth of an inch in width, and the end of the wire (1/20 of an inch) for a negation element, the needle was deflected, showing that this small galvanic arrangement was
6 Oct 6th 1842 } Experiments on the induction of the long wire and other parallel wire Sufficient to send a current through feet of wire and feet of earth [[sketch of wire routing from philos hall to my study]] The above sketch will serve to give an idea of the arrangement. Oct 7th Made a number of experiments to day with the the wire above described, and another placed parallel to it. A discharge [[overstrike**]] went [[**end overstrike]] of electricity from 3 jars of the French [[battery?]] was passed through the wire, and a needle placed in a helix connected with the secondary wire was magnetized. The arrangement was as follows. Two poles, supported by tripods formed of long slats of boards, were placed upright in the back campus, and over the tops of these a part of a wire was stretched parallel to the wire through the old college, and of a length equal to the whole breadth of the campus. This wire was continued backward on each side, until it extended to the two halls, it then crossed over with the two ends united, so as to form a complete parallelogram. In the first experiment, the distance of the [[means?]] and parallel parts of the two wires was 60 feet, and with this the needle placed in the helix used in the study for atmospheric electricity, was strongly magnetized. The parallel part of the second wire was next removed to the distance of 90 feet from that of the wire through the old college, and [[NEW PAGE]] 7 Oct 7th 1842 } Induction of ordinary electricity [[overstrike**]] at [[**end overstrike]] at a great distance again at this distance several needles were magnetized to a degree scarcely less than in the case of the least distance. In the experiments previous to the one now to be mentioned, the electrical discharge was from three jars. The charge was now reduced to that from one jar, the needle again came from the helix strongly magnetic. Next, the jar was removed, and a single spark thrown on to the suspended end of the conducting wire, while the other end was connected with the rubber. The needle with this was also magnetic but apparently not quite as strongly as before. After this, the second wire was removed from the long poles, and the parallel part stretched between the two upper windows of the first entry of the two parallel colleges. By this arrangement, the distance between the parallel parts was increased to 165 feet but not withstanding this great distance, the needle from the induction of a discharge of 3 jars was strongly magnetized. The experiment of a single spark was not attempted on account of the lateness of the hour. It would appear from the strength of the inductive action that at this distance, that the space between the two wires can be further increased. The needles in all the above mentioned experiments were magnetized in the same direction, indicating a current in of the running current
8 Oct 8th 1842 Removed the secondary wire to the farther entry of the parallel building. Sent through the primary wire a charge from three jars. The needle placed in the helix mentioned before, was again magnetic, and in the same direction as in the experiment of yesterday and the day before. Next sent a charge from a single jar, the needle was in this case magnetized in the same direction as before but not to the same degree of intensity. In these experiments, the whole parallelogram formed by the secondary wire, was carried back- ward, so that the farthest side was in the field beyond the society halls. The experiments were not continued this day on account of the dampness of the weather. In the morning a very heavy fog rested on the ground until about 10 oclock AM.. [[new page]] 9 Oct 15th 1842 Spent the forepart of this day with Lieut Lupoy of the Royal artillery in determining the dir and the intensity of terrestrial magnetism at this place. The station was that at which my observations were made on the intensity several years ago, namely in Mr. Clows field, south of the west college. The spot may be known by a depression in the general level of the ground, The station was the middle of this.
10 Thursday Dec 15th 1842 Mr Welsh, the engineer of the Raritan Canal; called on me this morning and gave [[strikethrough]] an account of a series of not very extensive but very interesting experiments, at which he had been assisting, relative to the velocity, range, and elevation of a ball, shot from Capt Stocktons large gun of wrought iron. This gun throws a ball of 212 lbs and is found to hit the mark with great precision, at the distance of 2730 feet. Mr Welsh has devised a very simple method of getting the velocity approximately by means of the deflection from a straight line. Thus, he measures the [[image]] fall of the ball by means of a series of screens placed at regular distances, through which the ball passes, and from these falls or deflections aa' bb' cc' &c he gets the times. The object of making this memorandum is to record my own idea of getting the velocity the ball at different distances, by means of a current of galvanism. Mr Welsh had thought that some method might be devised for using electricity, forgetting the velocity of the ball, but as he said, his knowledge of the agent was not sufficient to enable him to devise any means. The idea first occurred to me of using the revolving mirror as a means of determining the [[strikethrough]] ?[[/strikethrough]] velocity, but the electrical method which almost immediately suggested itself appears preferable. [[image]] The general arrangement will be something like this. A number of screens being erected at equal distance, a circuit ^[[of]] wire is made from each [[strikethrough]] screen [[/strikethrough]] to a galvanometer placed tangent or nearly so to a large graduated wheel, which is made to revolve once in a second or oftener. Suppose the wheel revolves once in a second and the needle of the galvanometer be made to carry a bar [[end page]] [[start page]] [[vertical line]] To test the truth of the indications of the needles, two sets of wires may be attached to the same. [[end vertical line]] N 13 Oct 1843 I have improved the plan of this apparatus, and published an account of it in the proceedings of the Phil Society. on its end so as to make a dot on the revolving cylinder at the moment the current is stopped by breaking the circuit. In this way the time may be noted to the 1000th part of a second. All the registers may be made possibly by one galvanometer, by using a current of less intensity than the one connected with the screens to deflect the needle constantly against a fixed pin. The connected current may also be used, if the register be made with a number of galvanometers. The ^[[same]] current may be continued around each. If it should be found necessary to use several galvanometers , then the inertia of each needle and the resistance of the point may not be the same. In this case, it would be necessary to test the accuracy of the register, and this could be affected by causing another wheel graduated like the first to revolve with two pins on it at intervals along its circumference. These could be made to interrupt two circuits [[strikethrough]] ? [[/strikethrough]] by striking against two wires in mercury, and as the distance of this pin apart are known, they would give the elapsed time which should also be given of the same duration by the other revolving wheel. The difference of the result given by the index wheel, and the other, would probably be constant, or at least it could be made approximately so. If one of the needles were a little heavier than the other, then the time noted would be a little later, comparatively, and the interval would be shorter than the truth if the heavier needle were the first to move. If the heavier were placed behind the other on the register, then the interval would be lengthened. The wheel may be made to revolve by means of a weight with thread over a pulley or cylindrical [[part ?]] of the axis, and the same axis furnished with two pairs of centrifugal balls to regulate the motion. If the wheel was a foot in diameter and revolved one in a second, then the 1/100th of [[strikethrough]] [[?]] [[/strikethrough]] second would indicate by about .4 of an inch, and the 1/1000th part of a second by .04 of an inch. [[end page]]
12 Dec 28th 1842 I have been studying for some days past [[capillary?]], and in connection with the subject, I have made to day a few experiments. First, to determine the affect of heat on [[capillary?]]. I wetted a tube of about 1/50 of an inch [[strikethrough]] with [[/strikethrough]] internal diameter with water, found the elevation of the liquid, when the tube was withdrawn from the water. I then plunged the same tube with its contained columns of water into a kettle of boiling water, when the [[grip??]] was withdrawn, the column was about to the tenth of an inch or about this quantity below its former level. This was repeated several times and always with the same result. Reflecting on this experiment, which in prin ciple is an old one, the thought occurred to me that if a column of water were placed in a tube in a horizontal position thus, [[image]] and heat applied to the one end, a motion should be produced in the column towards the other. The column will be equally attracted by the [[capillary]] in each direction, namely, towards a and b, therefore if we begin the attraction at one end, the column will move in the direction of the other. When the experiment was tried, the result was I anticipated. The motion of the column was quite rapid and could be moved several inches by the cautious application of the heat of the [[short?]] lamp. This experiment explains very satisfactorily the fact, mentioned by [[Raoult?]] in his chemistry of the motion of [[strikethrough]]heat[[/strikethrough]] oil along a wire, by applying a lamp to the wire of one side of the oil. The effect is given as an illustration of the repulsive power of heat. [[end page]] [[start page]] Another idea has occurred to me in the course of my reflection on this subject, in reference to the theory of capillary of [[Poision??]], namely that the legend is [[rarified?]] and condensed by the action of the [[capillary]] force. If this hypothesis be correct, should not the top of a capillary column depolarize light? Tried this by means of the polarizing apparatus of a [[?]] but with [[not?]] [[success?]] I have since [[writing]] the account of the machine for determining the velocity of a cannon ball, by means of electricity, conversed with Mr Saxton on the subject, and learned from him that there would be but little difficulty in constructing the revolving disk, it would be rendered sufficiently uniform in motion by means of a fly wheel, or by its [[over?]] momentum. He advises however a wheel or rather cylinder of not more than 4 or 5 inches in diameter, and [[says?]] on this spaces corresponding to the [[too?]] of a second could be [[marked]] out. I have since though of a method adjusting the several needles so as to advocate the difficulty attending the different degrees of [[invection?]], and this consists in deflecting the different needles to different distances by measure of [[pius?]], moved backward and forward by means of fluid screws. The needles could all be provided by attending all the wires on the wire for each, to the same screen, and when this was broken through, each needle should work the same moment on the revolving disc, if they did not, then the deflecting [[pews?]] should be so adjusted that the [[deserved?]] result would be produced. Another improvement was made in this method by causing the velocity to make it [[over?]] [[??]] see my [[??]], [[??]] [[??]] [[??]] [[??]] [[??]]. N B.another improvement in the arrangement, consists in smashing the [[earth??]] [[perform?]] the part of half the conductor.
14 Feby 23rd 1843 } Information from Mr. Quinby Mr. Quinby informes me that with an insulated lighting rod of copper 90 feet in height, terminated at the top by several points and connected with an insulated conductor below - and near the latter a ball connected with the ground to receive the discharge, he [[overstrike]] puts [[end overstrike]] has observed several times that when the pith balls connected with the [[overstrike]] pith balls [[end overstrike]] end of the rod exhibited no signs of electricity, and when a flash was observed at the distance of several miles, a spark passed between the end of the rod and the communication with the ground. In some cases, two sparks were observed in rapid succession with the same flash. He observed this for the first time in 1837. Feby 23 1843. The fact of the two sparks is in accordance with my new news of the action of the discharge of a Leyden jar. In connection with this subject the idea has just occurred to me that the several discharges in succession which may be observed in the discharge of a cloud, may in part at least be due to the reflex action of the electrical induction. [[end page]] [[start page]] March 5th 1843 15 Made a number of experiments today on the phosphorogence emination. 1st found that it would pass through a cup of water, the bottom of the cup was formed of a plate of quartz, and the sides of beeswax. 2nd It also passes through salt a plate of this mineral nearly half an inch thick, was placed over the paper box or tray in which the phosphorous was placed, the luminosity was as intense as if only air intervened between the spark and the substance. 3rd A plate of thin transparent mica was next interposed, the phosphorus remained dark 4th Next a plate of sulphate of lime was interposed the emmintion passed freely through this 5th Alcohol was next tried, and with the same results as that of the last experiment 6 A thick (one inch) crystal was next interposed, the phosphorescence was as vivid with this as without it. Feby 10th 7 The emination did not pass through a specimen of white carnilean which was pelucid, but not transparent. 8 Passed through smoky quartz, an inch thick. 9 Placed a quantity of the phosphorous between two plates of quartz, and then wound wire around [[image - 2 rectangular objects circled 5 times]] the whole, and passed a shock from the jar through the wire, but no effect could be perceived. The phosphorous did not become luminous.
16 March 10th 1843 Prepared phosphorous paper by first moisting or rather wetting the paper with gum water, and then sprinkling by means of a sieve, the powdered sulphuret of lime over the wet surface. The sulphuret of lime was prepared by first calcing a quantity of powdered oyster shells for at least an hour in an intense fire, then mixing with this powder 1/3 part by weight of flower of sulphur, and lastly heating the mixture for an hour in a crucible. This preparation is very sensible to the electrical emination. With a discharge from a single jar, the spark appearing between the points of two blunt wires, the phosphorous became luminous when placed at the distance of 54 inches from the spark. I observed one fact which may lead to some interesting results, namely that the emination which produces the phosphoro[[hole in page]] light looses more by being reflected from a surface of glass or of metal, than ordinary light does [[diagram in margin]] under the same circumstances. The phosphorous was so placed as that the direct emination could not reach it The arrangement was as shown in the margin [[underlined]] a [[/underlined]] is the mirror, [[underlined]] c [[/underlined]] the spark, [[underlined]] b [[/underlined]] the phosphoring, [[underlined]] s [[/underlined]] a screen. The light was more feeble from the mirror than from the direct radiation, although in the case of the latter, the phosphorous was placed at 4 times the distance I at first thought this was peculiar to the glass but found the same result with a metallic mirror [[end page]] [[start page]] [[overwrite]] Feby/March [[/overwrite]] ^[[March]] 11th 1843 17 Made a number of experiments with the object [[overwrite]] to [[overwritten by]] of [[/overwrite]] polar[[overwrite]] ize [[overwritten by]] izing [[/overwrite]] the phosphoregence emination, but was not successful. I however established the fact that the emination does not produce the phosphorescence when it is passed through a Nichols eye piece, combined of two pieces of calk spar, so arranged as to reflect under the extra ray - The light is much more vivid under two pieces of spar, making a thickness of 4 inches, than under an eye piece of one inch in thickness. The substance which is most impervious to the phosphorogence emination which I have as yet tried, is tourmaline. I can determine with some approximation to accuracy the comparative transfo[[blurred ink]] by making two holes in the same card and covering one with one substance and the other with another, the same powder being placed under each, the comparitive brightness gives the comparitive transmitting power. Part of the effect in reference to the now luminous result, when a Nichol's prism was used, may be ascribed to the fact that overly half of the incidental light passed through the crystal, the other half was reflected aside but result was so intense [[strikethrough]] when [[/strikethrough]] ^[[under]] the crystal and so feeble under the eye piece, that the difference cannot be attributed entirely to this cause. It appears to me that a simple polarized beam does not produce as much effect as a [[strikethrough]] a [[/strikethrough]] beam of ordinary light of the same quantity and intensity. I next placed a crystal of carbonate of lime above, and again below the eye piece, with the idea that the depolarization of the light
18 Feby 11th 1843 | Phos phorogence Emination makes a difference in the result but no peculiar effect was observed. The sulphuret of lime has been exposed to the air for several days and is not quite as sensible as at first or as it was yesterday, but by illuminating it several times by the discharge it increased very much in sensibillity, but it did not appear to remain luminous as long as it did yesterday. Found that the same phosphorescent light was produced by a coal of stone coal, intensely heated in the anthracite stove. The sulphuret of lime was defended from the direct heat by a thick crystal of sulphate of lime. The same substance is rendered luminous by a small degree of heat. The emination is screened by carnelian, and this substance, as I am informed by Dr Torrey, is supposed to be fused quartz, or it is quartz with a glassy structure. The action appears to diffuse itself. If a paper be placed over the tray with a hole in it, and another paper at some distance above also pierced with a small hole, then the ray will not diverge, but the whole surface of the mineral powder will exhibit the phosphorescence, the most intense light is confined to the center of the hole, but still there is light all around and over the whole surface. I find on comparing my experiments with those which are given in the Encyclopedia Britannica on the subject of phosphorescence, that those ^[[substances]] which I find do not transmit the phosphorigence principle are also incapable of being made phosphorescent by a discharge of electricity. [[end page]] [[begin page]] Feby 16th 1843 | Experiments on Mesmerism 19 [[three penciled in checkmarks]] Agreeably to appointment, I made some experiments today on a mesmeric subject, in order to test the truth of the assertion which had been made, that by throwing a person into what is called the mesmeric state, magnetism could be imparted to soft iron by a touch of his hand, and that his body would exhibit electrical phenomena. The subject was a young Negro, in the employment of a Mr. Anthon, a lecturer on Mesmerism. He appeared to be about 20 years old, not very intelligent, and was perhaps a good subject to be wrought upon, in the way of exciting his imagination. The magnetizer appeared to be an honest man, and fully convinced of the reality of the phenomena of animal magnetism. Before Mr. Anthon performed his operations on the boy, the frequency of his pulse was noted, and found to be 65 per minute, also a thermometer was placed under his tongue in order to determine the temperature of his body. On being asked if he perceived any peculiar feeling when the instrument was in his mouth, he declared that he did, that it made him [[underlined]] numb [[/underlined]]. After this he was placed on an electrical stool and made to touch a delicate gold leaf electrometer, but he gave no signs of free electricity. After these experiments, he was thrown into what the operator called, the mesmeric sleep. Of the nature of this state, I can say nothing from my own observation, although I am inclined to believe that the condition was not intirely feigned. The eyes were closed [[strike out]] and [[/strike out]] or nearly so, and the countenance assumed, or rather exhibited, a stupid expression, resem
20 July 16th 1843 that of a troubled sleep. At the command of the operator, he stood up and walked about the floor, stumbling against the benches and chairs. He was first brought to the electrical stool and ordered to stand on it, but he did not obey the [[magnetiser?]], and finally we were obliged to lift him on by man strength. The [[electrodes?]] was then placed in [[communication?]] with his hand, but it exhibited no signs of excitement, although the instrument was so delicate that the least touch of his coat with a silk handkerchief would make the leaves strike the side of the glass. This fact may perhaps have given rise to the assertion that by making what are called the [[passes?]] down the body, it would become electrical. a slight touch of the [[magnetizers?]] hand would be sufficient to produce this effect by the ordinary action of friction. Next his hands were placed in contact with the wires of a delicate electro magnet, and then [[passes?]] made along them, but the soft iron exhibited no signs of magnetism, although it was tested very carefully with iron filings. The boy appeared very reluctant although in the [[mesmeric?]] [[?]], to approach the apparatus. I next placed in his hands the two poles of a magnetic-electrical apparatus, the shocks of which were very severe, and could scarcely be endured by an ordinary individual. When the machine was put in operation, the [[muscles?]] of his arms were thrown into convulsive motions, [[end page]] [[start page]] July 16th 1843 21 and he exclaimed "I want to be waked up", "I want to be waked up". He however still kept his eyes closed and retained the same stupid and sleepy appearance, and as soon as he was released from the machine, he wandered, as it were, as far from the apparatus as the room [[strikethrough]] would [[/strikethrough]] would permit. When he was at [[strikethrough]] about [[/strikethrough]] the distance of about 18 feet from the operator, and his back to the [[?]], it was proposed by the Author himself that he should take the shocks inorder to test if the negro by sympathy, would exhibit any signs of [[?]] at the first shock given to Author, then face and neck of the negro were observed to be [[?]] affected. I was myself working the machine and giving the shocks and therefore did not myself see the face of the subject, but I did observe the twitching of the body. The experiment was by no means satisfactory, the boy could hear the [[sounds?]] of the machine and could [[perceive?]] the start of the person shocked. Whe Professor [[Maclean?]] took the shock instead of Mr A, the effect was said not to be produced. I can say nothing in reference to this observation [[?]] my position at the machine prevented my observing the effect. In order to avoid all perception of the ordinary kind by the boy in reference to the shocks given Mr A, the latter with this machine was placed in an adjoining room with the door open, but so that the sound would not be as perceptable as before and nothing could be [[seen?]] - with this arrangement, no effect was produced on the boy, however [[?]]
22 July 16th, 1843 the shocks might be which to Mr. [[A?]] [[induced.?]] [[Next?]] the door between the two rooms was shut and the boy placed close up to it so that Mr. A and himself were separated by only the thickness of the door, but in this case, as in the last, no effect could be observed, although shocks of great intensity were given to the operator. I forgot to mention in its proper place that the boy was brought near a large and powerful electro magnet when in full activity, and also when the contact with the galvanic battery was broken but no effect could be observed, although the [[Mesmerizer?]] had informed me, and probably believed what he said, that a magnet powerfully affected his subject. After this, Mr. A attempted to restore the boy to his natural state by a [[?]] of [[underlined]] [["passes?"]] [[/underlined]], motions with their hands upwards, while the boy was in the outer room, and the operator in the inner, but he appeared to make no progress - He next came in to the outer room, and commenced making the [[passes?]], but still the boy remained in the same state. At length by coming in contact with him he restored him to his natural state, the pulse was then at 75, but this acceleration was probably due to a violent fit of [[coughing?]] with which the boy was seized, just before waking. [[end page]] [[start page]] July 16th 1843 | 23 The result of these experiments prove nothing in favor of [[animal?]] magnetism, and do not even establish the fact that a person can be thrown into an unnatural state by the [[manipulations?]] of the [[Mesmerizer?]], although from the testimony of many respectable persons, I am inclined to believe that the [[immagination?]]can be so operated on as to induce a state resembling calulepsy or hysteria in case the subject is of a [[proper?]] temperament or of sufficient [[credulity?]]. The subject is just now attracting great attention in our country and in England, and although it would require a considerable amount of positive and definitive experimental evidence to induce me to believe in the sympathy of [[mind?]]or [[?]], such as is [[contended for?]] by the magnetizer, yet I do not think it philosophical to disclaim that the whole matter is too ridiculous to merit the least attention, since in this case, we assume that nothing can exist but what is already known to us. The probability in favor of the fallacy of the whole is certainly very great, but there [[may?]] be notwithstanding this, something in it, and at least it is a curious cycological [[phenomenon?]] that so many intelligent persons are at this time firm believers in the truth of the principles of this most improbable of all [[science?]], if it can be so called. [[end page]]
24 March 23rd 1843 Made an experiment today on the "pasivity" of iron. A piece of iron wire was heated, and then suffered to cool. On plunging this into strong nitric acid, no action was perceptible, and this state is called pasivity. The idea had occurred to me that perhaps if the wire were magnetized and demagnetized while in the acid, the natural state would return. On making the experiment however, the effect was not produced. The iron remained in the acid unaffected. The experiment consisted in surrounding the glass tube containing the acid, and into which the wire was dipped with a coil. When the passive wire was made, the negative element of a galvanic [[encircled]]couplet [[encircled]], the passive state was destroyed, and action produced. [[end page]] [[start page]] April 24th 1843 25 Being in Phild, I was requested, or I should say invited, to call and see a new microscope, lately imported by Dr. Beck(son of P. Beck Esq.) from England, this is the most perfect instrument of the kind which has yet reached this country. It is furnished with all the arrangements for ease of use as well as for exhibiting everything at present known, in reference to the microscope. With this instrument, I made two original observations, or at least two which I do not know to have been previously made. The first was in reference to starch. This substance is contained in minute [[membraneacious?]] bags which, when wet, swell and burst; the starch has therefore been considered a kind of organic substance. Each particle under the microscope presented an appearance similar to the nodules of indurated clay found about Albany [[image-drawing]] of the appearance of the figure. The idea occurred to me to view this by means of polarized light, the effect was beautiful, each particle of starch showed the action called depolarization of light and exhibited the black cross similar to that shown by a crystal of carbonate of lime when viewed parallel to the optical axis. This fact proves that the starch within the bags is in a state of segregation approximating crystalization. The black cross was not perfect, but the arms were curved somewhat irregularly the centre of the cross in each case was the same as that of the concentric circles which were observed on the surface of the particle without the aid of polarized light. [See the figure] The other observation with this microscope was in reference to capillarity. According to the theory of Poisson, the fluid which comes in contact with the plate of glass suffers a change of density. The idea occurred to me sometime ago, that if this were true to any appreciable degree, it might be rendered evident by means of the transmission of polarized light. The effect was as I anticipated. When a small quantity of water was placed between two glass plates, separated by a frame of thin writing paper, and this submitted to the action of polarized light
26 April 24th The apparatus being so arranged as to produce a dark field, the glasses with the contained liquid being introduced, a line of light was observed along the edge of the water. The effect appeared to be that of depolarization, but I should desire to make a number of experiments before asserting probably that the phenomenon was the one which I anticipated. Colours were also observed which were probably due [[strikethrough]] I was about to say [[/strikethrough]] to the curve of the water [[strikethrough// but this could not be the case since [[/strikethrough]] They say as it [[strikethrough]] extend one side [[/strikethrough]] passed from the [[strikethrough [[second?]] [[/strikethrough]] second side of the first curves of the [[circled]] meniscus [[/circled]] would be refracted from the perpendicular and as it entered the first surface of the 2nd limb of the same would be bent in the same direction. So that both limbs of the [[circled]] meniscus [[/circled]] would act as a prism to refract the light and produce colours but I do not see that a bright lining of light could be produced in this way so as to exhibit the appearance of depolarization. The only defect in the experiment which strikes me at present is that the field was not perfectly dark the polarization was effected by one of Nichol's prisms or rather Nichol's polarizing eye pieces. I intend to repeat the experiment with a darker ground produced by the polarization of a tourmaline. [[end page]] [[start page]] April 27th 1843 27 Commenced to day to experiment with the apparatice of Mallone, made for me by Rumkhorff of Paris. The cost of this set of articles, including a file of a single row of elements for determining the heat of the different parts of the solar spectrum, was 90 [[francs?]]. The galvanometer is furnished with an article for increasing to [[?]] consisting of two magnets to be placed on the top of the glass cover, and which, by being separated at their lower extremities, act with increasing power on the compound needle below and thus render it approximately nearer a perfect [[?]] state. The result of the experiments made with this apparatus are very satisfactory. It exhibits polarization of heat by means of two bundles of mica, also depolarization by placing between the bundles a plate of mica. Also the different transmissive power of different substances. particularly those of alum and common salt. I was much surprised at the effect produced by one of the articles. It consists of a pile of mica plates moveable around an axis and adjustable to any angle by means of a graduated arc. When the pile of mica was placed perpendicularly to the beam of heat, the needle stood at about 4°, but when it was placed so as to make an angle with the beam of about 33°, then the needle stood at 13 or 14°. This phenomenon is mentioned by Mallone in his article on polarization transcribed into the scientific memoirs. The explanation appears to be that the heat which passes the first lamina of mica is partially polarized, and is then in a proper condition to pass the next plate, which is placed at the polarizing angle. The same effect is produced by the transmission of light, if the article of apparatus by [[?]] before a beam of light at right angles to the same, and afterward turned into an angle of 33°, with it a great increase will be perceived in the quantity of transmitted light.
28 April 28th 1843 April 29 Repeated some of the other experiments of Mallone and gained some experience in the use of the apparatus. Tried with the Mellony galvanometer the thermopile which I purchased in London, found this nearly as sensitive as the new one from Paris - Also tried the single pair of plates, which I constructed some year or two ago - found that the approximation of the hand to this produced a wide deflection of the needle. [[image - cylinder with positive and negative charges]] Placed a small cup of platina on the face of the London pile [[page torn]], poured into this a few drops of water, the evaporization of the liquid produced a permanent deflection of 30 [[degree symbol]]. The pile was supported by passing it perpendicularly through a disk of pasteboard, which rested on the rim of a glass tumbler. When a crystal of muriate of soda of the size of grain of rice was thrown into the water in the little cup, a deflection of 20° degrees was produced by the reduction of temperature due to the solution of the salt. It is on this principle that M Peltier of Paris has formed an hygrometer which gives the rapidity of evaporation by the deflection of a needle connected with a cup, containing water and placed on the thermopile. Some experiments were also made, relative to the solution of tin foil in mercury. this gave cold although the mere contact of mercury with lead appeared to produce a slight increase of temperature. of this result at present I am not confident, further experiments will be required in order to establish it. [[end page]] [[start page]] May 1st 1843} Heat from the magnetization of Iron-- 29 Attempted to get an indication of an increase of temperature in the act of magnetizing a small bar of soft iron. for this purpose, two long wires were attached to the galvanometer, in order that the polarity of iron might not affect the position of the needle. [[margin]][[image--magnet suspended]][[/margin]] The magnet was suspended from a lamp stand, with the thermo-pile placed under it, and across this was laid the small bar of soft iron; the whole apparatus was supposed to obtain the temperature of the room, and then the thermo-pile with the cross bar of soft iron, was raised up by moving up the ring of the brass ring stand until the iron touched the magnet, care being taken not to impart sensibly any heat to the several parts of the arrangement. When the experiment was made the needle was observed to move slowly from rest at zero to [[edited from 25 to 15?]]°. This effect was produced 3 times in succession; the motion of the needle was not as if by a single impulse as in the ordinary cases of the action of the pile when affected by radiant heat, but as if from a source of heat gradually conducted through or from the interior of the iron. *If there be no falacy in this experiment, it shows the evolution of heat by the change produced in a bar by the process of magnetization. There are however several sources from which the heat may be derived as well as from the magnetization of the iron. 1st. It may come from the percussion of the iron and the magnet. 2nd. from the condensation of the air which takes place when the bar is suddenly brought in contact with the face of the horse shoe. I must make farther experimts on these points tomorrow. The experimt may be made with the horse shoe in a vacuum, and by bring the iron fully in contact with the face of the horse shoe, the sources of heat before mentioned will be obviated. * Repeated these experiments on 2nd of May (page 32), found no Result of the kind.
[[start page]] 30 May 1st 1843 In the afternoon of this day, I made some experiments with the thermo pile exposed with its reflector attached on the radiation of [[distant?]] objects. I had at first concluded to place a [[image]] small sheet iron stove in an open field, and endeavored to determine the distance to which the [[strikeout]] [[?]] [[/strikeout]] stove might be [[]] and still its heat be sensible to the thermo apparatus. The idea afterwards ocurred to me to try the affect of a distant cloud. The thermoscope was at first directed towards the clear sky, when the needle moved to the side indicating a reduction of temperature and stood at 48°. The tube or rather [[]] reflector, was then directed to a bright cloud which was in the same part of the heavens and but a few degrees distant from the part to which the cone was first directed, the needle now stood at 25°. The experiment was made after the sun had left the cloud, with the same result, except that the difference was not now as great as before, the needle moved from 48° to 34°. When the mouth of the [[]]reflector was lowered, so as to take in the rays from the distant horizon, then the needle advanced rapidly towards the warmer side, indicating an increased eradiation from the ground. These experiments lead me to suppose that the instrument may be improved for meterological observation by using a [[]] [[]] cone and connecting this with a straight tube blackened on the inside and highly polished on the out [[image]] make a large cone so as to fit the end of the "large reflector" use this for heat of moon. [[end page]] [[start page]] May 2nd 1843 attempt to get heat from [[]] action 31 1. Repeated the experiment with the magnetization of the bar of soft iron and with the same result as stated page 29. The needle [[]] gradually from [[underlined]] minus [[underlined]] 2° to [[underlined]] plus [[underlined]] 14°. The same experiment was tried again, and with the same result. The needle was next supposed to come to rest, and then the bar was seperated from the magnet. After the whole had attained the temperature of the room, the needle was slightly disturbed and [[]] through and arc of about 30°. While the articles used in the last experiment were slowly attaining the temperature of the room, I next tried an experiment with a thermopile of a single hair, for the purpose of determining if any change of temperature was produced by cappillarity. The thermopile was inserted into [[image]] the neck of a flat bottle, and the whole [[]] closed with a cork, so as to prevent the evaporation of the liquid contained in the phial. In this exp. I found considerable difficulty in bringing the extremity of the within the phial to the same temperature as that without. When the needle came to rest and then the phial was shaken, so as to throw the water up on the end of the pile, the needle [[]] to 22° degrees and then settled at about 12° on the side of the [[]], which indicated an increase of cold instead of heat. Repeated this and found that the needle [[]] [[]] to the [[underlined]] cold [[underlined]] side , and then by throwing up the water so as to wet the end of the pile, the motion took place in the [[]] [[]] but I afterwards found that this return was due to the heat of y fingers, acting by conduction through the glass. The causes of error in these experiments are very numerous and must be guarded against with great care. connected the coil with [[]] machine which was kept in action for nearly an hour, but the heat of the bar was very slighly increased. [[end page]]
32 May 2nd 1843 [[boxed in]]Heat from the magnetization of iron[[end of box]] [[image in left margin]] Made a new arrangement of the apparatus for seperating the small bar from the keeper, this consisted in fastening the bar across a hole in a small board, and placing this on the magnet inverted. The board is elevated or depressed when the bar is to be brought in contact with or seperated from the magnet. When the bar was seperated from the magnet, the needle moved about 2 1/2° to the [[underlined]] cold [[/underlined]] side. Also when the needle was again suffered to come to rest, and the bar was suddenly brought into contact with the magnet, the needle again moved to the [[underlined]] cold [[/underlined]] side about 2° degrees. These experiments would appear to show that no heat is produced by the magnetization of the bar, and that the effects I obtained before were due to the friction of the pile on the surface of the bar. The last arrangement was such as to prevent any rubbing, and also to lessen the effect of percussion. [[underlined]] May 3rd [[/underlined]] When the same exp. was repeated this morning, the needle again moved to the [[underlined]] cold [[/underlined]] side about 10°. These changes appear to be owing to the difference of temperature in the thermo pile, and the magnet, the latter being large and consequently requiring considerable time to assume the temperature of the [[circled]] circumambient [[/circled]] while the former being small soon feels each change of temperature. Try this exp. with a long bar and a coil, one end of the former being thrust into the latter, the pile at the further end. [[end page]] [[start page]] May 3rd 1843 33 [[image]] Made an experiment to day to determine the polarization of a conductor, when a current of galvanism is passing through it. It is well known that when a current is passed from the circumference to the centre of a wheel, or in the opposite direction, that motion will be produced in the wheel, provided a magnet be placed on each side of it. Now this effect could not take place according to my view of the phenomenon, unless there was a degree of persistence in the direction of the current. It was with the intention measuring this persistence that this experiment was instituted. The apparatus was however too heavy to exhibit any effect even if it existed, since no motion was produced by placing a powerful horse shoe magnet on the plane of the axis of the plate. I intended to give motion to the plate, supported as it was on friction [[strikeout]] [[soles?]] [[/strikeout]] by means of a small weight [[strikeout]] passing over [[/strikeout]] suspended from a string suspended over an axle. The friction was so great that no difference in the velocity could be observed, wether a current was passing or not. When however the the magnet was placed with its legs on each side of the wheel, the force of persistance was sufficient to stop the descent of the weight. Next tried to get indications of[[strikeout]]rom[[/strikeout]] heat from the magnetization of a bar of soft iron - For this purpose the bar was placed in the lecture room, at the distance of 27 feet from the galvanometer; yet at this distance the needle was slightly affected with the polarity of the bar, and in the direction which would indicate heat when the pile was connected. The result of the exp. was very unsatisfactory. the heat if any was developed could not be eliminated from that of the galvanic current around the iron, and the difference of temperature of the bar and the pile.
[[start page]] 34 May 3rd 1843 Next prepared some of the sulphuret of calcium, by mixing pounded calcined oyster shells with 1/3 of their weight of sulphur. First tried if this would become luminous by the galvanic spark, or rather from the coil with a rod of iron in its axis. The effect was apparently as great in proportion to the size of the spark, as in the case of the discharge from the Leyden Jar. The powder was supported on a plate of rock crystal, in order to hold it immediately over the mercury from which the spark was taken. I next tried if the emination from galvanic spark would pass through glass. The powder was removed to a plate of glass of the same thickness as the plate of rock crystal, but although the same number of sparks were taken, the powder remained quite dark. It would appear from this that the spark from mercury gives the same emination as as that from the electrical discharge. Tried the comparative transmissive power of glass and allum, found that [[underlined]] alum [[underlined]] was nearly the same as rock crystal. Next tried the polarizable capacity of the phosphogenic emination, found that it was polarizable, by placing one of the small trays which I made of sheet lead, under the mica pile of Mellom's apparatus [[image]] first with the mica horizontal, and again with the same inclined to the polarizing angle. A greater effect was produced with the latter position of the mica than with the former. The effect was not however as great as in the case of light. [[end page]] [[start page]]May 4th 1843 35 Next arranged the apparatus for ascertaining the reflectability of the phosgenic emenations. [[image]] A [[underlined]] metallic [[/underlined]] mirror was arranged so as to throw the reflection of the spark down through a hole in a plate, underneath which the lime was placed, when the discharge was made the sulphuret of lime glowed very brightly. Found a source of error in the last experiment, the light direct from the spark was not sufficently screaned. Remedied, tried the experiment again, but the same result was produced. The lime was luminous and not much less so than by the direct discharge. Tried the same experiment with a peace of black glass. The result was the same, but the amount of reflected light much less than from the mirror of speculum metal. Repeated the experment of the polarization of the phos. emination, and from the result there can be no doubt of the fact of the polar capability of the emination. The mica pile was placed horizontally then the discharge made. The lime was dark, the pile was next inclined in an angle of about 33[[degree symbol]] with the ___ The spark, again pass. the lime now was luminous. The light was then suffered to disappear, the pile was returned to its horizontal position, no effect. The pile again inclined at the polarizing angle, now the lime exhibited a [[strikeout]] shining [[/strikeout]] shining surface. [[image]] This establishes the fact. In the forgoing experiments, I used the apparatus for supporting the little pans which is represented in the margin. [[end page]]
36 Monday May 8th 1843 Phosphorogenic emination transmissibility of different substances for Experimented on the relative transmissability of different susbstances for the phosphoregenic emination. The following appears to be the order as obtained by comparing one with another. [[underlined]]1st series of exp[[/underlined]] Rock crystal Calc spar Sulphate of Barita [[underlined]] 2nd series [[/underlined]] Rock crystal Calc spar very little difference Salt Alum [[underlined]] 3rd series [[/underlined]] Sul barita White glass Viol[[e]]t [[strikethrough]] Red [[/strikethrough]] glass Red glass Mica [[underlined]] 4th series [[/underlined]] White glass Mica Tourmaline [[underlined]] 5th series[[/underlined]] Rock crystal Sulphate of lime Calc spar [[underlined]] 6th series [[/underlined]] Fluor spar Calc spar Sulphate of Barita Transmitted the emination through quartz cut perpendicularly to the axis, and obliquely to the same, but could not perceive any difference in the intensity of the light. Tried the same experiment with calc spar, but no difference in the result was observed, although the difference in thickness of the two pieces of spar was. On sunday the 7th - There was a thunder shower which as usual came from the south west and passed at a great elevation above Princeton - several needles were magnetized in my study by the flash. with the same apparatus which failed a few days since to give any results when it was connected with the long wire. It was on the 7th connected with the roof of the house. [[end page]] [[start page]] Tuesday May 9th 1843 37 Mr Professor Hamilton informes that within the last three years he has observed 5 or 6 cases of houses struck with lighting, and in each of these the discharge was on the end of the gutter or in the vicinity of the same. He knows of but one exception to this, and then the whole house was surrounded by water as if the building were on an island. It was struck at the chimney. The house was in a hollow - does not know if the chimney had fire in it at the time. This fact in reference to the gutter [[overwritten]] are [[/overwritten]] is in accordance with the explanation I gave of the phenomena of the striking of old Mrs Hamiltons Houses (see back vol) May 9th. Commenced to day with the manipulation of the Daguerrotype process in order to study the chemical emination in connection with that of the Posphorogenic. [[image: a box with 6 small squares inside it that are numbered, placed in two rows of three; 3 squares in the first row, labeled 1,2,3 from left to right; 3 squares in the second row labeled 4,5,6.]] A prepared plate was placed under a block of wood, through which holes were cut as represented in the figure, and over these holes were paced plates of different transparent substances, [[underlined]]Viz[[/underlined]] over No 1 mica, No 2 glass, No 3 Calc spar, No 4 Salt, No 5 Quartz, No 6 alum. The plate was then exposed to the diffuse light of the sky for about 2 minutes and then removed to the mercury. While the process was going on, the iodized plate underneath could be distinctly seen, and it appeared to change colour under each but under the cal spar the heat appeared dif[[hole in page]]nt. The final result of the experiment was not satisfactory, the whole effect was overdone, the spots No 1 2 & 3 were more solarized than those marked 4 5 6 - Tried the same experiment, but the time was again too long to indicate any difference of result. The plate under each opening in the wood was marked as before. [[end page]]
38 Tuesday May 9th 1843 Chemical Emination Tried the last experiment again. The plate with the different substances as before was exposed to the diffuse light of the sky. for 25 seconds, all the openings produced spots on the plate but those under the mica, and salt appeared a little less intense. The experiment must be repeated several times, inorder to bring out the facts relative to the specific influence of the different screening substances. Repeated the same experiment again with the same arrangement, the plate was exposed however during 12 seconds instead of 25. The result was that no difference could be perceived in the intensity of the impressions from the different openings. The impressions were as vivid as in any of the other experiments, although the light was gradually declining. Repeated the same experiment, the time of exposing the plate to the light, being 7 seconds. The spots were well developed on the plate, but no difference or very little, could be observed. One + 4 [[underlined]]ie[[/underlined]] the salt and the mica, appeared rather more blue than the others. In the foregoing experiments, the plate has been coated first with the vapour of iodine, and then to render it more sensible, has been placed over the vapour of the clo[[hole in page]]e of iodine. Inorder to decrease the sensibility of the plate, the exposure to the [[clornette?]] was omitted, and the plate exposed during about 10 seconds to the light of the sky. The impressions all came out as strong as before, the one under the glass being the more intense if anything. [[end page]] [[start page]] Wednesday May 10th 1843 [[underlined]]Chemical emination[[/underlined]] 39 Repeated the experiment with the plate prepaired as in the last experiment, the time was shortened to [[underlined]]6[[/underlined]] seconds. The light however is gradually diminishing. The plate again received an impression from each opening, the one under the glass was apparently the most intense although they were all faint. The light at the last experiment was quite faint, the sky was cloudy [[illegible strikeout]] the clock struck 6 at the time of the experiment. From all the results obtained this afternoon, it would appear that the phosphorogenic emination, and the chemical are as distinct as the luminiferous and the calorific. [[dividing line across page]] [[underlined]]May 10th[[underlined]] It is will known that when a discharge of electricity is passed through an orange, an egg, or an apple, and even through the thumb, the whole interior of the substance becomes illuminated by a phosphorescent red light. Made some experiments to day, or rather this morning, on the penetrating power of the light from the electrical discharge. 1 Four cakes of about one 4th of an inch in thickness of white wax was placed on a stand, before the spark from a Leyden jar, as in the arrangement [[image]] of the margin, and then the light observed through. The effect was beautiful and brilliant, the whole surface of the wax appeared to be illuminated with a white light. The experiment is a good class exhibition. I next placed a tube of pasteboard in front of of the wax and the eye at the other end, the effect with this was still more striking. The result could be seen without closing the windows. [[end page]]
40 Permeability of Electrical Light Wednesday May 10th 1843 The white wax was removed and its place sulphur with a cake of common bees wax unpurified was substituted in its place. The light still appeared through this, although it was just an inch and a half thick, and apparently impervious to the light of the day- The light was not however perfectly excluded from the inside of the tube as a small quantity entered between the end [[strikeout]] of the [[strikeout]] and the surface of the wax. The two lights howere were not conpounded with each other, that though the wax from the machine was red while, the other was the white light of day. [[image]] The defect in the arrangement mentioned in the last paragraph was remedied by fitting to the end of this tube a short cylinder of copper, and pressing the latter into the bees wax. With this, all extraneous light was cut off and the discharge [[strikeout]] through [[/strikeout]] appeared through of a beautiful red color like that of the sun through the fingers. The points in this experiment were placed at the distance of 3/4 of an inch from each other and 1/4 of an inch from the surface of the wax. Next the points were joined by a piece of wax softened so as to bury them in the substance of the [[mass?]], but the effect was not as great as with the [[strikeout]] wax [[/strikeout]] points at a ^small distance from the surface. The points were now removed to the distance of about two inches from the surface , the light through was still perceptible but very faint. [[end page]] [[start page]] Wednesday May 10th 1843 [[underlined]]electrical ligh[[/underlined]] [[underlined]] chemical emination[[/underlined]] 41 To compare this with the light of the clouds, [[strikeout]] wax [[/strikeout]]the same cake of wax with its tube was placed before a hole in a window shutter, and the light observed through. The effect was much stronger than I expected, the wax appeared of a beautiful crimson, and the [[strikeout]]intense [[/strikeout]] light was as intense as that from the discharge of the jar. From this result, it appears that there is nothing peculiar in the permability of wax for the electrical light. Whether the same is the case in reference to other substances,remains to be seen by experiment. Next placed a piece of wax a little yellower and thicker, before the end of the tube. The electrical light did not appear through this, although the light of the cloud was faintly perceptible. Resumed the experiments on the chemical rays: placed a prepared plate under the piece of wood pierced with holes, and brought over this the points used in the last experiments, but no impression could be produced on the plate from the electrical light, although the machine was turned for 5 or 6 minutes. The light from the clouds gave an impression on the same plate in the course of 20 seconds. This experiment combined with that of the phosphorescence, produced under the same circumstances mark a strong distinction between the chemical and phosphorogenic eminations. A series of different coloured glass was nex placed over the openings in the wooden block before mentioned, and these again over a prepared plate. The impression were very different. The order was as follows : [[underlined]]white[[/underlined]],[[underlined]] violet [[/underlined]], [[underlined blue[[/underlined]], (distinct), [[underlined]] green [[/underlined]], [[underlined]] salmon [[/underlined]], & [[underlined]]red [[/underlined]], no impression. The transparency of the green and blue was very nearly the same. [[end page]]
[[start page]] 42 Wednesday 10th May 1843 [[underlined]]Phosphoroscence emination[[/underlined]] Contrasted the effect of the light in the last experiment with that of the electrical spark in the production of phosphorescence. The same glasses resting on the wood block were placed over a shallow box containg the sulphurette of lime and the spark from a single phial passed over them. The only plates under which the lime became phosphorescent, was the thin clear glass and the violet, but under the latter it was much less intense than under the former. All coloured glasses appear to lessen the transmissability of the phosphoresence principle. The refrangibility of the phosphorosence emination was very prettily exhibited by placing the larger lead box containing the sulphurette of lime under a plate with a slit in it, and then passing the discharge over the slit at the distance of about an inch, the [[strikeout]] lime being at about the same distance below the slit. The image of the slit was depicted on the surface of lime in a well defined [[strikeout]] broad [[/strikeout]] narrow line. The same experiment was repeated with the difference of placing a prism of salt over the slit, the impression was now increased 5 or 6 times in width and the whole impression thrown to the other end of the box by the[[underlined]] refraction power [[underlined]] of the salt prism. I next made some experiments on the refractive[[?]] transmissability of this emination through different liquid substances. The liquid was placed in a cube made of the cylindrical part of a 4 ounce phial to which a bottom of a plate of rock crystal was cemented. [[end page]] [[start page]] Wednesday 10th May 1843 order of phosphorescence transmissibility of [[underlined]] liquids [[underlined]] 43 The first series was with [[underlined]] water bichromate [/underlined]] of [[underlined]] potassa [[/underlined]] and [[underlined]chlorate [[?]] of lead [[/underlined]]. The water is not perfectly [[transoophorescent?]]. The bichromate is less so , and the perfectly transparent [chlorate? of lead is almost as impervious as glass or mica. 1st series [[underlined]] the order is as follows [[/underlined]] 1 transparent water 2 boron solution bicarb pottass dark 3 transparent chromate of lead - dark found this a solution of [[circled]][[acetic?]][[/circled]] acid [[underlined]] 2nd series [[/underlined]] 1 water dark 2 nitric acid dark 3 chlorate of lead all transparent [[} grouping items 1 through 3]] [[underlined]] 3rd series [[/underlined]] water solution of alum sulphate of magnesia minerals of ammonia x camphor water [[Grouped]]all transparent all transmit like water[[/grouped]] (see [[strikeout]] page 44) [[underlined]] 4th series [[/underlined]] sulphate of copper nitrate of copper [[grouped]]coloured blue transmit much more feebly than water[[/grouped]] 5th series sulphate of zinc transparent but transmits badly The bad transmitters according to these experiments are as follows: [[underlined]] nitric acid[[underlined]] [[strikeout]] [[difulconate?]] of lead [[/strikeout]] sul acid, n. 47 [[underlined]] sulphate of zinc[[underlined]], [[underlined]] acetate of lead[[underlined]], (page 44) [[?]] n. 47, [[underlined]] acetate of zinc [[underlined]] (p 46), [[underlined]] sulphate of lead [[underlined]] (p. 46), alcohol p 47, [[end page]]
[[start page]] 44 Thursday 11th May 1843 Procured this morning a transparent solution of acetate of lead. The acetate is often of a milky colour but it may be rendered transparent by the addition of a small quantity of the pure acetate acid. This salt of lead like the other salts of the same metal which I have tried is nearly impervious to the phosphorogenc eminations. [[note in left margin beside this paragraph]] * [[/note in left margin]] Next tried a plate of transparent camphor, found this nearly as impervious as mica. More impervious than glass indeed I am not sure but that it is to be classed with mica. The plate of camphor was next submitted to the influence of the chemical examination, over a sensible plate in connection the acetate of lead and a plate of common glass. The [[strikeout]]whole [[/strikeout]] plate under each became blackened without any apparent difference. [[underlined]] the time of exposure was 10 seconds [[/underlined]] Next tried the transmissability of camphoretted water : found this about as permiable as water. [[in left margin beside this paragraph]] x [[vertical line]] [[/in left margin]] Next prepared a sensible plate, and placed over it a thin plate of mica, and over this again the pointed wires, or rather the blunt ends of the wires from the electrical machine. After turning the machine for about 10 minutes, the plate was impressed with the effect of the chemical examination. Repeated this experiment with a lens - of small focus (one inch) ; the ends of the wires connected with the machine wire about 2 1/2 inches from the plate with the lens interposed, with this arrangement no effect was produced. [[end page]] [[start page]]Thursday 11th May 1843 45 Repeated the last experiment with the same arrangement as in the first case, and with the same result--the impression was very distinct-the time was about 10 minutes--This establishes [[in left margin]] [[underlined]] * [[/underlined]] [[/in left margin]] the fact that the electric spark can produce the effect. [[dividing line across page]] In making the last experiment, a fact was observed of some interest apparently--When the thread of light of the electrical machine was viewed through a glass coloured deep [[smudged]] red [[/smudged]], it appeared as if cut into two by a black line through the middle thus: [[drawing]] as in the figure, except that the space which appears white in the drawing is black in the spark. It appears from this experiment that the middle part of the electrical spectrum is absorbed by red glass. [[dividing line across page]] The transparent plate of camphor mentioned on the last page was next tested in reference to its thermacy. For this purpose, it was compared with salt. alum & glass. [[image beside results below: hand with index finger extended, pointing rightward.]] alum gave 4 1/2 degrees of deflection camphor--4 1/2 glass(trans) 38 degrees glass(ground) 28 degrees salt -- 90 degrees Repeated this with the same general result. Camphor scraped, let pass a few more rays. From this result it appears that camphor is as thermal as alum. The experiment must however be repeated with a perfect polished plate of camphor. * The same effect would have been produced by the light of the clouds in 5 or 10 seconds.
46 Friday May 12th 1843 Tried this afternoon the transmissibility of sulphat and acetate of Zinc - found that they should be classed with nitric acid and the other substances which have little transmissibility Made a comparative experiment on the effect of the exposure of a quantity of the sulphuret of lime to the reflected sun light and the electrical spark. The effect was much more brilliant with the electrical discharge once made from a single jar than from the reflected sun light for 60 seconds. By reflected sun light is here understood the ordinary reflection of bright sun shine from buildings and other objects. The phosphorescent light becomes quite brilliant after a few moments exposure of the sulphurate for a few moments to the direct action of bright sun shine. [[_________]] [[underlined]] Friday [[/underlined]] 12th Examined the plate of camphor used in the last experiment in reference to its action on light; found that it possessed the polarizing structure as indicated by its depolarizing power between the tourmalines. I was occupied during the remainder of this day in preparing a frame to support a tube on the end of Melonies pile to study the radiation from the moon and the sky. Did not however, succeed in getting the apparatus arranged in time for the experiment. [[end page]] [[start page]] Saturday May 13th 47 Prepaird a plate for the chemical emination submitted it to the electrical spark screaned by a plate of glass and a plate of [[strikeout]] sulp [[/strikeout]] carbonate of lime placed side by side. I could perceve however very little impression and no difference in the action on the plate under the two substances. Tried alcohol, acetic acid , & [[strikethrough]] [[illegible]] [[/strikethrough]]the sul acid: The order of transmissability was as follows: [[the following note appears to the left of the bracketed list]] coloured less transparent solutions [[bracketed list]] water acetic acid ether alcohol sulphuric acid annisceeded [[/bracketed list]] [[the following note appears to the right of the bracketed list]] all nearly opaque, the pos-genic emanation Next tried oil of anniscede, found it more opaque than alcohol acetic acid acetate of lime Found that [[underlined]] Ices transmitts [[/underlined]] the emination as readily as water. Also Rochelle Salts transmits [[list]] copal } opaque to the emination & saltpeter } Next tried spirits of turpentine, found it in comparison with water almost opaque. Horn depolarizes light, but it transmitts the phosgenic emination about as glass. Tried relative transmissability of fluid and crown glass found little or no difference.
48 Monday May 15th 1843 phosphoregenic emination under water Tried on saturday eving at the time of full moon to produce the phosphorous glow on sulphuret of lime by means of moon light, but I did not succeed. The experiment however was not decisive the lime may not have been in proper condition, although when I tried it this morning with the electrical discharge, it answered very well. Tried this morning a number of substances in reference to the transmissability by the phosogenic emination, among others the sulphate of potassiam a transparent salt, this gave a beautiful violet coloured light [[in margin]]Remarkable effect of sul pot[[/in margin]] as well as transmitted the influence to the lime below. The phosphoresence was more brilliant than with the lime but did not continue so long nor was it acted on at so great a distance. This is an interesting fact. Exposed the same substance, sulphate of potassa, to the direct light of the sun for a bout a minute, then removed it into the dark, found it phosphorescent but much less so than when exposed to the discharge of the Leyden Jar. I next discovered the remarkable fact that the phosphorescence of the sulphate of potash was produced as brilliantly under water, [[underlined]] ie [[/underlined]] when the substance was immersed in water, as when in the air. Tried the same experiment with the sulphat of lime, found the same result both with the sun light and that of the electrical discharge. When the sulphate of potassa is powdered, it gives a beautiful effect with the electrical discharge, more brilliant but less durable than the sulphuret of lime. [[end page]] [[start page]] Monday May 15th 1843 49 Made a series of experiments on different substances relative to their transmisability. The following is the result: [[Comment to the left of the following bracketed list]] Solids [[/End of Comment]] [[Comment to the right of the following bracketed list]] Powder under these Brilliant [[/End of Comment]] | Borax | | Sulphate of potassa | | sulphate of soda | | Citric acid | | Rochelle salt | [[strikethrough]]Hyposulphate of soda[[/strikethrough]] [[Comment to the right of the following bracketed list]] Powder dark under these [[/End of Comment]] Salt petre Tartaric acid Solids Hyposulfate of soda [[Comment to the right of the following bracketed list]] Powder light [[/End of Comment]] Trans Muriate of Barreta Solution ammonia (doubtful) [[Comment to the right of the following bracketed list]] Powder dark under these [[/End of Comment]] Muriatic acid Spirits of turpentine Trans Arceneous acid Solutions Ammonia Phosphoric acid
50 Tuesday May 16th 1843 Repeated the experiment of rendering the sulphur[[retic?]] luminous under water after the substance had stood thus immersed 30 hours and more, it appeared as brilliant as that which had not been thus placed. Submitted the sul of lime to the light of a candle and then examined it in the dark; found it phosphorescent. The phosphorogenic emination therefore exists in the light of a candle. I have before found that alcohol is a bad transmitter of the phosgenic emination to test this again. I placed in a shallow glass vessel a few crystals of sulphate of potassa and over them about 3/4 of an inch of alcohol. The crystals [[strikethrough]] however [[/strikethrough]] remained dark when the discharge of electricity passed over them, although when they were shaped in water in the same way they glowed with great brilliancy. Tried the transmissibility of white wax, found that the lime became luminous faintly below a plate of white wax 1/4 of an inch thick. Found that common chalk became quite brilliant by a discharge of the jar at the distance of 4 or 5 inches, also that the same screening influence was exerted by glass and other substances, - also the screening took place in the case of the light from the candle; this was not however as fully proved as it might be. [[end page]] [[start page]] Wednesday May 17th 51 According to [[circled]] Becquerel [[/circled]], there are three substances which give light during a change of form from the [[insertion]] liquid to the [[/insertion]] solid [[strikethrough]] to the liqui [[/strikethrough]] state. Sulphate of potassa, [[circled]] arcenious [[/circled] acid, & muriate of ammonia. -- Since the sulphate of potassa is phosphoresent I thought that perhaps the other substances might be so also, tried the [[circled]] arcens [[/circled]], but got no result. It should have been however the crystallized transparent [[circled]] arcenic [[/circled]] and not the ordinary kind (Kane). Friday June 9th. Since the last date, I have been engaged in lecturing to the senior class, and have also attended the centenary anniversary of the american Phil society. At this meeting, I made a communication of the results of my investigation of the phosphorogenic emination. also gave an account of the method I have proposed for determining the velocity of a cannon ball. The meeting was well attended, 45 communications were made but I was not much impressed with the importance of this method of advancing science. The temptation to make a display and to bring forward communications merely to produce an effect for the moment is very strong, and while the mere declarations on the foundation of other men's labours produces quite an effect, the man of true science who modestly brings forth the result of his labours is scarcely noticed, provided he has arranged nothing for effect. These reflections are not made inreference to my own case, since I was more complimented than I deserved, but they are the sober inference from an attentive watching of the result of the meeting. I am not sure that the British association has much advanced the cause of science, except in the case of meteorology and magnetism.
52 Friday June 9th 1843 The idea occurred to me while in Phi[[superscript]]o[[/superscript]]. that possibly the emination from the electrical spark was not of the same intensity throughout the whole line of the discharge, and perhaps it might be compared to the poles of the discharging wires. To test this, a [[strikethrough]] hole [[/strikethrough]] [[insertion]] slit [[/insertion]] was made in two plates and these slits were placed transversely to the path of the spark so that the lines underneath could not be reached by the emination except from a single point of the spark, with this arrangement it was found that the light was produced from every part of the line of the discharge, but that it was much more intense at the two ends. To test this more accurately another arrangement was made by which the impression from the line could be made at once from several points, and the intensity of the action [[insertion]] from each [[/insertion]] compaired at once with one another. For this purpose three holes were cut in a plate of mica [[strikethrough]]and the [[/strikethrough]] so that one hole would be directly under each pole of the discharger and the other be midway between the other two. When the discharge was made close to the plate of mica, so that the emination [[strikethrough]] from [[/strikethrough]] [[insertion]] through [[/insertion]] each hole might make its impression on one spot without any effect from other parts of the spark; the impression at the middle hole produced a faint phosphorescence which continued a few seconds and then disappeared while those at the two ends continued to glow for more than a minute. I have called the openings holes, they were rather slits, so that the impressions from the whole width of the spark might be viewable [[strikethrough]]from [[/strikethrough]] on the line through each slit. [[Image at bottom of page of a rectangle with the three slits]] [[end page]] [[start page]] Oct. 3-1843 Heat of a thunder cloud - 53 Since the last date, I have been engaged in college and other duties, an I am now for the first time since then enabled to resum the business of experimenting. This being our autumnal vacation, I hope to have a few weeks of uninterrupted leasure. I must however make the best use of this since on account of the new arrangements of college vacations during the next year, my time will be more than usually occupied. [[illustration in the left margin of a tubular device on a pole that resembles a windsock fully extended, might be a telescope.]] Agreeably to the suggestion given at page 30, during the summer I have [[insertion]] had [[/insertion]] attached to the thermo pile of Melloni's apparatus a tube of pasteboard covered on the outside with gilt paper inorder to reflect the heat from the outside. The object of the tube is to screen the pile from all radiation except such as proceeds from some circumscribed portion of space. The instrument thus furnished gave very satisfactory and interesting results. When turned towards a cloud of a white appearance, it indicated an increase of temperature over that of the blue sky, the needle taraversing in some cases an arc equal to 50 degrees. As the instrument was lowered towards the horizon, the heat was increased-the experiment being repeated in the forenoon and afternoon, but perhaps the result would be different were the observation made early in the morning or late in the eveng, or rather after sundown. When the instrument was [[jesccled?]] to a dark thunder cloud, it indicated [[strikethrough]] an [[/strikethrough]] a diminution of temperature. This is in accordance with the theory of Peltier. Found the heat decreased towards eveng, from the smith downwards.
[[Start Page]] 54 Tuesday Oct 3rd 1843 Does ordinary elect pass along the surface? Made a series of experiments to determine whether ordinary electricity in passing through a conductor passes on the surface, or through the entire mass. For this purpose, a spiral was made of a number of turns of a piece of bell wire and this was placed with a needle in it in the axis of [[image- tube with line running through it, line/wire spiraled in the center of the tube and straightened again to end]] a hollow iron tube and a shock from a single jar sent through the tube, but the needle exhibited no signes of magnetism. The same wire and spiral were next placed on the outside of the tube, the shock again passed, and now the needle was found to be magnetic. The experiment was repeated by substituting a tube of tin foil around a paper cylinder, the needle spiral and connected wire being placed in the inside. The needle exhibited no signes of magnetism, but when the needle and spiral were arranged on the outside, magnetic effects were produced. The intensity of the charge of the battery was about the same in the different experiments. The discharge was from a single jar highly charged--with a larger battery less highly charged the effect would probably was different. [See American Endycopedia Dobsons Edition] Repeat this exp with battery of several jars less highly charged, ___ Also with galvanism the wire soldered to the tube. [See Exp of Mr Kennedy, I think in the Phil Mag Irish academy] [[Written on side of sheet with line leading to this part of text]] The surface alone is not however to be considered in erecting lighter rods. [[underlined]]Made an other experiment. [[/underlined]] Put sulphate of pottassa in cup of water, introduced under the surface of the same two insulated ends of wires, sent shock through water from single jar, The salt became luminous and was broken by the concussion of the water. [[end of page]] [[New page]] Wednesday Oct 4th 1843 Lateral Induction. Ordinary Electricity 55 Water appears to conduct electricity badly, and when a large quantity is to be transmitted, the effect is the same as that of sending a discharge through the air. Try if the same noise and projection of the water would be produced, which I observed in this experiment when the discharge is made between two plates of [[water? metal?]]. [[image- battery created with bottle on wax, wire leading from top of bottle to wire suspended on flat platform, other end of wire leads to wax circle on bottom of bottle. Tube around wire on platform has spiral lines leading from center out]] Sent charge through the horizontal wire a b, while a ball c was placed at a small distance from the circuit and seperated from it by a tube of glass which surrounded the wire. The jar was insulated, so that the inside or outside could be rendered redundant at pleasure. In all cases induction was produced in the wire c d, which was connected with the earth at its lower end, or rather was united to a wire which passes out of the window and is soldered to a copper plate buried in the earth. The current was from the horizontal wire towards the earth, both when the outside had the redundant electricity and when it was deficient. In one experiment the most compounded of the three spirals used gave the needle the least degree of magnetism of the three, and this would seam to indicate that action consists of an oscillatory motion, or that there is an action and a reflex action. In another experiment, a spark passed from the horizontal wire to the ball c and then the current as indicated by the magnetization of the needles, was towards the horizontal wire, of this however I am not very sure. To prevent the passage of the electricity from the wire to the ball, the glass tube was employed. [[end page]]
Wednesday Oct 4th 1843 Transverse Induction Continued _ Made the same experiment as described on the last page, with the exception that the battery of Dr Franklin was substituted for the jar, with this, the effect was not as great as with the jar. The needles were not as strongly magnetized, and those in the spirals less compounded were more intensely magnetized than the others. This result would also seam to indicate a wavey motion in the disturbance of the electrical plenum which as I suppose fills all [[space?]] [[image]] Placed a ball with the wire leading to the earth in connection with it opposite the points of the French discharger to determine if the electricity passing through the air would produce the induced current in the long wire. The result was as I expected, a strong current was exhibited by the magnetization of the needle in the spiral. [[margin]] Exp.1. [[/margin]] [[line separating paragraphs]] [[margin]] Exp.2. [[/margin]] Next the two ends of the wire of the discharger were placed in contact, so that the discharge might pass without making an explosion in the air, the same effect was produced as before, but the needles appeared a little more strongly magnetised. In the above experiments, the ball was seperated from the conductor by a plate of glass put between them. [[line separating paragraphs]] [[margin]] Exp.3. [[/margin]] The direction of the induction was not altered by changing the direction of the discharge through the discharger [[underscored]] c d [[/underscored]]. I have not yet however proved that this induction is independent of the [[face?]] electricity of the jar. [[line separating paragraphs]] [[margin]] Exp.4. [[/margin]] [[image]] Fastened by a little wax a piece of thread to the ball of the Lyden jar, and another piece to the outside. then after charging the jar the inside was touched so as to draw off the electricity until the two threads [[end page]] Thursday Oct 5th 1843 Induction Continued 57 stood at about the same angle with the axis of the jar, indicating that the quantity of free electricity in each was equal. When the discharge was made, the needle in the spiral was made magnetic, but not as strongly as with [[_]] [[margin]] Exp.5. [[/margin]] That the effect does not principally depend on the redundant electricity of the jar, is evident [[strikethrough?]] from the fact that when the jar was removed and the sparkes from the machine passed through between the points, no magnetism was imparted to the needle. [[illustration]] When the jar is discharged while standing on a cake of wax, and a wire is placed near it, the needle the [[strikethrough?]] spiral becomes magnetic the current being from the jar. Also a single spark thrown into the inside of the jar magnetizes the needle with the same arrangement as in the last experiment. NB. To prevent any direct communication of electricity from the outside of the jar, a plate of window glass was placed between the jar and the ball. [[line underscoring paragraph]] Exp. 7. [[Diagram of Leyden jar with Electrical wand on right. On left wire ab with resistor with arrow pointing upwards, while arrow pointing downwards on wand. Also written in pencil ..See page 103]] When an arrangement like that shown in the figure was made, the needle became magnetic and indicated a current in the adverse direction to that of the jar. The magnetic effect was feeble and this is what was to be expected since the return currant in the same wire would obliterate the direct, at least in part. Oct. 6 If a wire were attracted to the [[strikethrough]] conductor ab [[underscore a underscore b]]connecting it with the earth, an other effect would probably be produced, and perhaps this would be different, if the attachment were made at the top or the bottom of the conductor. [[Diagram Leyden jar with electrical wand on left, wire ab on right with resistor. a marked at bottom connection and b marked at top with a ground wire connected at a]] Tried the experiment when the wire connected with the conductor was placed at [[underscore]] a [[/underscore]], the bottom, no magnetism was developed in the needle, but when the same wire was connected with the upper part of the conductor as at [[underscore]] b [[/underscore]], a powerful developement took place showing a current upwards. Also when the discharging wire was removed, a current was produced as in exp above. [[End page]]
58 Thursday Oct 6th 1843 The effect in the last experiment may be explained by considering that the induction down the wire when placed at the bottom tends to invert the current by induction in the vertical conductor. [[diagram Leyden jar capacitor with wire halo connected to metal band around base of jar and wand]] With the arrangement shown in the anexed figure, no current was produced, or at least I should say, no development of the magnetism took place. ___ When however the circuit was opened, and the discharging wire attached to the ____ The weather to day is so [[impossible?]] for electricity that I have directed Sam to change four of the Daniel batteries. Placed around the room a strap of copper, and over this at the distance of three feet a wire of three [[spires??]] into which a set of magnetizing spirals was introduced, but no effect was produced, when a current was passed through the strap or ribbon from a Daniels battery of 4 elements. Hence the induction from galvanism in a short coil is much less intense than from the discharge of Lyden jar. [[end page]] Monday Oct. 9 59 [[Annotation in margin]] This result cannot be obtained by the discharge of a jar, but by two balls one + and the other minus. [[/End of annotation]] [[Diagram showing ball a[positive charge] and a ball b[negative charge] with current flow from point f to point e moving left to right. above the a ball on top of the flow line is a d marked negative and over the b, a c marked positive with arrows denoting counter flow between c and d]]. Repeated the experiment given at top of last page, found the result as shown in the diagram. [[underline]] a [[/underline]] and [[underline]] b [[/underline]] are two balls connected with the outside and inside of a jar. When the discharge is made, currents are produced towards [[underline]] d [[/underline]] from each direction, and [[strikethrough]] towards [[//strikethrough]] from C in each direction. When the discharging wire connected with the earth is connected with the point [[underline]] e [[/underline]], the current is downward, but when it is connected with f it is also downward, but this effect is due in all probability to the actions on the part of the wire between [[underline]] d [[/underline]] & [[underline]] c [[/underline]], the sum of the actions tend to send the current in the direction of [[underline]] c [[/underline]] [[underline]] d [[/underline]]. Exp.2 See vol.2. p282 June 6th 1842 [See vol.2. p282 June 6th 1842]] [Diagram of Leyden jar with wand positive at top negative at bottom, wire joint on left, wire with direction arrow downward at resistor mark]] When this arrangement was made, which is shown by the anexed figure, the current was downward [[crossed out]] and this was probably due to the action of the releving of the tension of the redundant electricity of the inside [[/crossed out]] Exp.3 [[Diagram of Leyden jar with wand with square drawn behind top metal ball in jar, with wire running downward with variable resistor on wire marked b]] Next arranged the apparatus with the wire leading to the earth at top, but contrary to my expectation, the current as indicated by the needle, was towards the earth. Tried this many times in succession with needles no 5, in all the spirals of the set the result always the same [This result is in accordance with the exp on top of page 61. The whole charge passes through the knob.] Thinking the effect was due to the return wave, I used needles of a larger size No 1 and placed these in the least compound part of the set of spirals, but the effect was the same, the needle was still magnetized so as to exhibit a current downwards.
60 Monday Oct 9 [[entire paragraph notated as error, as per left column notation]] after several attemps to descover the cause of the anomaly which was exhibited in the last experiment, I found it due to charging of the pane of glass which I interposed between the two balls to prevent the transfer. When this was removed, and the balls seperated to the distance of two inches, the needle in the spiral [[underline]] b [[/underline]]] indicated a current in an upward direction, or in accordance with my previous hypothesis, and also my previous experiments. The effect of the glass was to produce such an arrangement as was given in the experiment above, the last on the last page. The one side of the glass was charged + and the other was (the one next the receiving ball of the induced current) was negative per the result. In all the subsequent experiments, the use of glass must be resorted to with a knowledge of the effect. I was mistaken in the last result, the glass being removed, the needle still indicates a current down tows the ground, and no arrangement I have yet been able to make will produce a contrary result. Exp. 4 [[Diagram shows a circle with perpendicular line on top with positive with line and loop underneath showing a variable resistor]] When the jar was removed and and an insulated plate led over the ball, the current was upward at the moment a spark was drawn from the dist. end of the machine. The effect cannot therefore be due to the redundant or free electricity, for this would tend to produce a different result. [[Initialled NB in right margin]] The fact that a current is sent off in every direction from a wire transmitting a discharge, will explain the induction produced in thunder storms. See a case in Comptes Rendus for 1843 Aug 4th Cathedral of Strasbourgh. [[end page]] Monday Oct. 9 61 [[Diagram of plane with two wires at perpendicular angles to plane at either end. Wire running through two balls at top of each perpendicular wires, wire joints, protruding from plane marked at one end a and the other end b. + sign over perpendicular wire on right with directional arrows pointing to the left. A fuse with wire and resistor just after wire joint b]] [[note in left margin]] Exp. 1 [[/end of note in left margin]] Arranged the apparatus as in the figure-placed the receiving ball near the plus end, made the discharge. The needle indicated a current from the wire. The receiving ball was then moved toward the negative end, the result was the same, the needle still indicated a current towards the earth or from the wire. The induction therefore through the whole wire appears to be due to an accumulation of the fluid in the wire, and not to its being in a polar state the one end being +, and the other minus, and this is in accordance with the puzzling results I have obtained in the experiment of this morning. [[note in left margin]] Exp. 2 [[/end of note in left margin]] Next attached a ball to the end of the wire [[underline]] a [[/underline]]while the other end was placed in connection with the conductor of the machine. When a spark was drawn from the ball, a current was produced in the discharging wire [[underline]]from [[/underline]] the earth contrary to the direction of the current I have before obtained. [[note in left margin]] Exp. 3 [[/end of note in left margin]] Next connected the ball [[underline]] a [[/underline]] with the earth and then threw sparks on [[underline]] b [[/underline]]. The needle was now magnetized as if a shock had passed through the wire, or in such a manner as to indicate a current from the wire to the earth. Experiment 2 was varied by connecting the end b. with the machine, and then drawing sparks from the same end, the needle was magnetized by an ascending current. The results obtained in Experiment 3, page 59, are in accordance with the facts here obtained. The jar is charged, and the electricity as it passes out of the ball, sends a current in the direction towards
62 [[check mark]] Monday Oct 9 much stronger than that produced by the transmission of the ball from the plus state to the neutral. Or in other words, the induction is due to the sudden passage through the ball of all the electricity of the jar which for a moment produces a greater effect than the discharge of the ball, as in the case of exp 4, [[strikethrough]] 1 [[/strikethrough]] page 60, with the insulated plate. All the experiments would seem to indicate that the wire acts as though a quantity of additional electricity were added to it for a moment. Perhaps this may not be the case in a very long wire. In reflecting on the subject of the passage of electricity along the surface of a body, I am led to conclude that it does not follow that a greater conducting power will be given to a conductor of metal by flattening it so as to increase the surface. The opposite sides which by this process are brought into more near approximation, will cause a greater repulsion of the electricity and thus increase the resistance. [[vertical marginal entry underlined]] See Snow Harris' paper [[/vertical marginal entry]] [[vertical squiggle in margin along this paragraph]] The tendancy to spread must be greater in a long than in a short conductor, because the attraction for the negative surface [[strikethrough]] from [[/strikethrough]] to which the discharge is tending, will prevent a wide deviation from the direct path, but this tendancy to spread will be greater in proportion to the length of the conduction. Faradays proposition relative to the equality of the amount of negative induced electricity, and the positive is correct - the negative ball will not be as strongly electrified, but the difference will be made up by the induction on the [[covering?]] objects. [[drawing showing positive and negative balls]] [[end page]] [[start page]] 63 [checkmark] Tuesday Oct 10 1843 [[vertical squiggly line]] The spreading of the electrical discharge from a prime conductor is shown in the experiment of passing the spark through a vacuum. The beams fill all the bulls eye receivers. Try this experiment in the dark, with the the discharge from an insulated Lyden jar. The experiments of Priestly on the lateral discharge are not in discordance with the results I have obtained. A spark passed from the outside of the jar to a neighboring conductor and back again, without imparting but a very small charge to the conductor. [[illustration of pane of glass and wire with arrow pointing downwards in left margin]] [[underline]] Wednesday [[/underline]]Oct 11th Charged a pane of glass coated with tin foil on the two faces with the idea that the direction of the induction with this apparatus might be different from that with the jar, but the result was the same, the direction of the current as indicated by the magnetisation of the needle, was constantly from the glass, whether the receiving ball was in contact with the negative or positive side of the plate. The experiment was repeated many times in succession, and always with the same result. It appears that the induction is produced by the sudden transfer of the electricity from one side to the other of the glass, and that the effect is felt through the glass, the distance or rather difference of distance may be considered as nothing. When the discharge of the plate was produced by drawing off the electricity from the + side of the plate, the receiving ball being on the minus side, the needle was magnetized by an ascending current, as might have been expected. That the suggestion I stated above is true, is shown by the fact that when the jar was discharged slowly
64 Wednesday Oct. 11th [[squiggly vertical line] attaching to the discharging rod a needle so as to make the transfer by degrees, the needle was magnetized in the opposite direction, or so as to indicate an ascending current towards the [[underline]] plus [[/underline]] side of the plate. [[Diagram in margin is glass plate with electrical wand passing over the plate, with wire dropping down. Wire is shown with resistor and arrow pointing up along the wire. Plate is turned at an angle so that the wand indicates one ball on one side of the glass and the other ball on the other side.]] Repeated the above experiment with the different side of the glass, and found that in all cases when the discharge was made either rapid or slow, the needle on the negative side was [[strikethrough]] [[?]] [[/strikethrough]] magnetized by a descending current, while that in connection with the plus side of the glass with a sudden discharge was downwards, while with a slow discharge, upwards The discharge was upwards or towards the positive side of the glass, even when a spark passed between the needle point and the tinfoil of the glass. I found it is not invariably the case that a slow discharge gives a current downwards from the [[underline]] minus [[/underline]] side of the glass. Sometimes the result is different, but this may result from the spark drawn first by touching the side. The change of the direction in the above experiments depend principally on the extra spark being drawn from one or other side, but all the experiments I have thus far made, indicate that a sudden discharge of the glass plate sends a current from the plate from both sides to the ground. [[end page]] [[start page]] Wednesday Oct 11th 1843 √ 65 Made an experiment of the haphazard kind on the fringes produced by light. Sent charge from jar through two wires, which formed the apparatus of the two openings in diffraction, but no effect could be observed - The apparatus was formed by connecting a wire, as in the figure, on the surface of a piece of mica, and then two ends of this brought into contact with the opposite sides of a charged jar. The experiment must also be tried with galvanic electricity - The wires pass in opposite direction and may on this account vary the result, since the induced currents may neutralize each other. [[Drawing to the left of the above paragraph of the glass pane with connecting wire and plus sign top left and bottom right]] Arrange the discharges, as in the [[anexed?]] figure, first took the induction from [[underline]] a [[/underline]], and then from [[underline]] b [[/underline]], on each side of the break. The result however was the same, the needle was magnetized by a [[descending]] current in each case. [[Illustration of the experiment described above to the left of the text]] See Priestley on lateral discharge. Made an arrangement of wire similar to that represented in the figure, connected one end with the machine [[underline]] a [[/underline]] [[underline]] b [[/underline]] -, parallel to this I placed a wire [[underline]] e [[/underline]] f, which was joined at its two ends at g, when the machine was turned so as to charge, [[underline]] h [[/underline]] [[underline]] i [[/underline]], and then the electricity drawn off at [[underline]] a [[/underline]], a current was produced in [[underline]] e [[/underline]] [[underline]] f [[/underline]]. The [[side?]] in the spiral no 1 gave a current -, those in no 2 and 3 gave a current +.
66√ Wednesday Oct 11th 1843 [[vertical squiggly line]] Repeated the last experiment with needles in all [[strikethrough]] the set of [[/strikethrough]] spirals of the set. That in no 1 gave a - current, all the others gave + currents. In these two experiments needles no 5 were used. Tried the same experiment with larger needles no 2, the result however was the same, the needle in no 1 gave a - current , in the other spirals a +. It must be recollected that spiral no one is more complex than the others. Repeated the same experiment with the exception of drawing off the electricity from the end farthest from the machines, now the current as indicated by all the needles was adverse. The condition of the two experiments was not precisely the same, the whole discharge through the wire of all the electricity of the machine took place but this was not the case in the other case. [[following paragraph has a box drawn around it with notation in left margin stating Observation on Rain under trees during fog.]] [[underline]] Thursday [[/underline]] The sky last night at 10 oclock was perfectly cloudless, and yesterday was delightful. This morning a thick fog covers the face of the earth so as to obscure the sun, and the phenomenon of [[underlined]] rain under [[/underlined]] the trees is exhibited. I have directed an assistant to take the temperature of the air, and also that of the trees, by swing the thermometer first in the air, and next placing it amid the leaves of the trees. Temperature of the air 58◦, of the leaves 56½. This was however at the time the air was rising in temperature, and whenthe trees had almost ceased to rain. [[end boxed paragraph]] [[end page]] [[start page]] Thursday Oct 12th 1843 [[vertical squiggly line]] Shock passed through wire in water √67 [[image- drawing of small oval dish appearing to be referenced basin placed on a table and labeled "a" to the bottom right of dish. On opposing left and right side of dish are two small posts with loops on top. Left post has a negative sign above while the right has a positive sign. What appears to be a wire is passing through both post loops and coursing down towards the basin. A slight rounded bend on each side of wire above the dish occurs and the wire culminates in a half-moon shaped bend in the center of the wire; the half-moon portion dips into the basin. The tips of each end of the wire after they have passed through the post loops, out away from the basin, both end in loops as well.]] Placed a wire in a basin of water and sent shocks through it, while the finger was immersed in the water, a sudden concussion was felt by the finger, as from a shock from the jar passed through it, and this happened at each discharge. The effect was the same with a large wire, also when the conducting wire was grasped by the hand a sever concussion was felt when the discharge passed through, and this is not produced as has been supposed by the redundant redundan [[strikethrough]] d [[/strikethrough]] t electricity according to the explanation of [[Beot?]], but by the transfer of the electricity of the jar and the consequent induction. It was the same action in all probability which produced the electrical phenomena within Mrs. Hamilton's house at the time the discharge passed along the outside of the building (see vol 2nd pages ). (See also the proceedings of Amer. Phil. Society.) When the finger is placed in the water, and the conductor interrupted, quite a severe electrical concussion is felt, and this is the case when the finger is placed at the end of the dish at [[underlined]] a [[/underlined]]. According to the experiment of Wheatstone, the electrical action, whatever may be its nature, arrives last at the middle of the length of the conducting wire. This is in accordance with the theory of one fluid; the moment a spark starts from the knob, an equal quantity of the electricity on the end of the wire in contact with the outside of the jar is released, and rushes into the jar, so that a wave of rarefaction runs along the wire from the negative and [[strikethough]]in one direction [[/strikethrough]] towards the middle, and one of condensation for the other. These waves pass each other at the middle, and oscillate backwards and forwards several times.
68 Thursday Oct 12th 1843 [[vertical squiggly line]] The weather is unfavourable for experiments with the electrical machine, and I have therefore directed sam to put in operation four of the cups of the Daniell's battery. Attempted to get a current between two coils with the ends open, but did not succed. [[text in remainder of page enclosed in a box]] Made some rough experiments on the heat produced in a conducting wire by the transmission of an electrical current, the result however was not very satisfactory, the time required for the long bell wire to arrive at its maximum temperature was much greater than I had supposed. I devised the following apparatus for the purpose of detering the heat, namely: [[image of apparatus as described in the text below]] A copper wire is passed backward and forward over the face of a [[underlined]] pile [[/underlined]] with a single row of elements, and over this is placed a plate of polished or gilded metal to reflect all extraneous heat. This apparatus is introduced into the circuit at different points, and the effect noted. On this subject, see Pelteas exp Annals de Chem vol- [[end page]] [[start page]] [[underline]]Saturday[[/underline]] Oct 14th 1843 69 Made an experiment to get electricity by a change of the molecular arrangement of a metallic wire. For this purposed, I introduced into the circuit with a copper wire and the French galvanometer a [[underlined]] thermo pair [[/underlined]], so that the electricity might pass with more difficulty in one direction than the other, and thus a current be exhibited. But when the wire was stretched, no effect was observed, although the wire became quite hot. Why should the stretching of a wire thus increase the temperature? The fact is in opposition to the general law that heat is absorbed when the density of a body is lessened. The wire when stretched occupies more space than before. (See Philosophia Magaze for year 1845) [[vertical note in left margin]] molecular action [[/note in left margin]] Tried an experiment on the heat produced by stretching a piece of indian rubber. When the rubber was stretched, it produced a great increase of temperature, and when it was worked backward and forward, there was a permanent increase of the heat. When a piece was broken, and the fresh formed surface applied to the thermo-pile, an increase of heat was indicated. (give this under the head of cappillarity) Monday Oct 16th 1843 I have thought of a plan by which the velocity of the galvanic current can be measured. For this purpose the wire should be wound [[strikeout]] around [[/strikeout]] at intervals around a bundle of fine wire, and over this a long wire, to produce a secondary spark at the moment of breaking the primary current, the sparks might be inspected by means of the revolving mirror, or by means of the revolving cylinder according to the plan I have proprosed in my new method of determining the velocity of a projectile. The plan of making a hole with the spark:
70 Monday Oct 16th 1843 The experiment of Wheatston should be repeated and various partial conducting substances interposed, such as a tube of water, alcohol, sulphuric acid &c. Also the intensity of the discharge as well as its quantity should be varied and the effects carefully noted. [[small circuit diagram]] Arranged this afternoon a wire across the campus for transmitting a discharge of electricity from the Phil Hall to the well opposite our house and back through the ground [[strikeout]] from [[/strikeout]] to Mr. Clow's well at the end of the Phil Hall. The same wire had been stretched across the campus from the time of my lectures last winter, until the present, but it was taken down today and insulated at the windows of the Hall and library by [[sketched image of a tube]] placing a tube on a round stick, and over this the wire, the stick was then fastened across the window. Also another wire for receving the induction was stretched across the campus from the Mr Maclean's well to Dr. Carnahan's. The circuit of each of these was tested by means of the galvanometer with a small single battery the negative element of which was formed of a silver thimble, and the positive of a single point of zinc plate. At first with the wire near the old college, I found some difficulty in completing the circuit. There appeared a break somewhere, and after considerable search, it was found at our house at a point where the wire passed behind the window shutter. When the circuit was completed, the needle was violently agitated by the wire touching of the front of zinc to the surface of the acid - This result, which is a repetition [[END OF PAGE]] [[note: a page has been torn or cut out of the journal between pages numbered 70 and 71]] [[TOP OF PAGE]] Tuesday Oct 17th 1843. 71 of what I obtained last Oct., is still a matter of surprise of that [[strikeout]] the [[/strikeout]] electricity of such feeble intensity should pass through such a distance of partially conducting matter, could scarcely have been expected. [[sketch image of a basin with two wires on opposite sides]]. An opening was made in the same circuit and a basin of rain water was introduced, the points of the wire being about 8 inches apart. It was thought that in as much as the current had passed through several hundred feet of water or moist earth, that it would exhibit but little additional diminution but in this I was much mistaken, the effect appeared to be reduced at least one half by the small addition to the resistance of the water. This result is curious and deserves further investigation. {In accordance with the law, the earth offers little or no resistance, Dec 1845} The deflection of the needle of the same apparatus was considerably less when placed in the circuit between the wells of the President's and Vice President's houses. From this, it is probable that the two wells are not in aqueous connection. {Important result unless difference in the length of wire caused the difference in the effects, Dec 1845} The first experiment in induction with this arrangement was by sending a current through the first circuit and magnetizing a needle in the second. The magnetizing spiral was placed near the President's well and was the same which I have used before both [[strikeout]] from [[/strikeout]] for induction from an arrangement of this kind and the electricity of the clouds. The needle was strongly magnetized by a current [[underlined]] adverse [[/underlined]] to that of the battery current. Same experiment was several times repeated with the same result, each discharge gave indications of an [[underlined]] adverse [[/underlined]] current.
72 Tuesday Oct 17th 1843 [[vertical squiggly line]] Induction at a distance Long waves across the campus Attached to the secondary current [[described?]] yesterday, one of the sets of spirals of different convolutions, and also the compound spiral used yesterday. The following was the result: 1st With one jar highly charged [[following text enclosed in a box]] * Spirals NO A NO 1 NO 2 NO 3 NO 4 Dynamic [[defl?]] -22 -12 1/2 -17 -5 -3 [[/end box]] 2nd One jar [[following text enclosed in a box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Dynamic [[defl?]] -20 -3 -15 -3 +1 [[/end box]] 3rd One jar [[following text enclosed in a box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Deflec -20 -10 -18 -3 -1 [[/end box]] 4th One jar 2 sets of spirals (Stronger charged loud snap [[following text enclosed in a box]] Spirals 1st set NO A NO 1 NO 2 NO 3 NO 4 Defl [[underline]] -45 -45 -40 -20 -4 [[/underline]] Spirals 2nd set NO A NO 1 NO 2 NO 3 NO 4 Defl -45 -38 -23 -2 [[/end box]] 5th [[following text enclosed in a box]] Spirals 1st set NO A NO 1 NO 2 NO 3 NO 4 Def -25 -12 -18 -4 -0 Spirals 2nd set NO A NO 1 NO 2 NO 3 NO 4 Defl -17 -12 -4 -0 [[/end box]] [[underline]] NB [[/underline]] All the results give an induced current opposite to that of the battery * I have designated by NO [[underline]] A [[/underline]] the spiral used yesterday and also last Oct [[end page]] [[start page]] Tuesday Oct 17th 1843 [[vertical squiggly line]] 73 Induction at a distance Long wires across the campus 1st 2 jars [[following text enclosed in a box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Defl. -20 -3 -7 -11 -0 [[/end box]] 2nd 2 jars [[following text enclosed in a box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Deflec. -20 -20 -3 -12 -2 [[/end box]] [[image = diagram of suspended conductor]] Suspended large conductor one spark With this arrangement the needles came out magnetized - (Weather changed more damp) [[centered horizontal line]] Next used Dr Franklin's battery of 24 jars - charge 100 units Air to damp for the jars without warming to release the charge. Wednesday Oct 18th 1843 Attached two wires across the campus from Phil Hall to library. Return of one through the wells of the President and Vise President, the other (the discharging wire), through the other two wells. [[Image to the left of text - Diagram showing placement of the wires between the wells]] Wires at first about 18 inches apart. One jar [[following text enclosed in a box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Defl 65 +33 +26 +6 0 [[/end box]] Current in the direction of the discharge
74 Wednesday Feb 18th 1843 [[vertical squiggly line]] Experiments on parallel wires across the campus Arrangement the same as before [[underline]] One jar [[/underline]] higher charge 1 [[following text enclosed in box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Defl Needles no 5 + 50 +25 +35 +37 +42- [[/end box]] [[In the left margin]] Wires at the distance of about 18 inches [[/End of margin note]] One jar 2 sets spirals 2[[following text enclosed in box]] Spirals 1st set NO A NO 1 NO 2 NO 3 NO 4 Defl +60 -46 -55 -56 -52 Spirals 2nd set NO A NO 1 NO 2 NO 3 NO 4 Defl -45 -50 -50 -45 [[/end box]] This result is due to a much [[underline]] stronger charge [[/underline]] Tried the same with larger needles in one and small in the other set 3 [[following text enclosed in box]] Spirals 1st NO A NO 1 NO 2 NO 3 NO 4 Defl (needles 5) +65 +58 +45 +28 -22 Spirals 2nd set NO A NO 1 NO 2 NO 3 NO 4 Deflect (Large needles No 2 +56 -0 +6 -18 [[/end box]] This result is in perfect accordance with my previous results and [[underline]] anticipations [[underline]] One jar 4 [[following text enclosed in box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Def(Needles No 5) +35 +40 -32 -40 -38 Spirals NO A NO 1 NO 2 NO 3 NO 4 Defl. [[underline]] [[darning?]] need. [[/underline]] +38 -33 -40 -40 [[/end box]] This charge was very heavy jar warm [[end page]] [[start page]] Wednesday Oct 18 1843 [[vertical squiggly line]] Experiments on parallel wire 75 [[underline]] One jar small charge [[/underline]] [[following text enclosed in box]] Spirals NO A NO 1 NO 2 NO 3 NO 4 Defl Small needles No 5 +55 +47 +38 +33 +24 Defl [[Darning?]] needles +55 +38 +34 +18 [[/end box]] [[underline]] One jar [[/underline]] charged to 60◦ of Electrometer [[following text enclosed in box]] Spirals small needles 5 NO A NO 1 NO 2 NO 3 NO 4 darning needles +55 +45 +44 +35 +32 +50 +44 +42 +25 [[/end box]] [[vertical note in left margin]] Wires at same distance[[/note in left margin]] One jar charged to 60 [[following text enclosed in box]] Spirals small needles No 7 NO A NO 1 NO 2 NO 3 NO 4 +45 +40 +37 +28 +2 Darning needles +58 +42 +40 +30 [[end box]] Pint jar [[following text enclosed in box]] Spiral small needles No 7 NO A NO 1 NO 2 NO 3 NO 4 +45 +38 +33 +17 +0 Darning needles +50 +42 +30 +2 [[/end box]] Jar removed spark from the machine (number of sparks) [[following text enclosed in box]] Spiral small needles No 7 NO A NO 1 NO 2 NO 3 NO 4 +33 +25 +2 -2 -2 Darning needles +45 +45 +22 -2 -0 [[/end box]] Single spark (from machine) [[following text enclosed in box]] Spiral small needles No 7 NO A NO 1 NO 2 NO 3 NO 4 +31 +30 +30 0 0 Darning needles 35 +32 -2 0 [[/end box]]
76 Thursday Oct 19th 1843 [[vertical squiggly line]] When the two end of the long secondary conductor wire grasped, quite a smart shock was felt in each hand. I next tried the method of determining the direction of the current which was used by the Italian Philosopher Matteucy (see Annals de chimie 1841), which consits in piercing a hole in a thin piece of writing paper. The perforation as it is well known, will be nearer the negative point, and hence the direction may be determined. The experiment was perfectly successful, and gave a current in the adverse direction to that of the battery discharge. Made a galvanometer of about 300 turns well seperated by cement, suspended a needle in the centre and connected this with the [[strikethrough]] coil [[/strikethrough]] circuit at the same opening where the needles were placed yesterday, when the current was sent through, the long conductor across the campus, the needle was moved and indicated a current in an [[underlined]] adverse [[/underlined]] direction to that of the battery current. With three jars charged nearly to 90◦ the effect was the same except the needle was more moved. To be sure that the effect was due to the action of the current, the direction of the current as regards the electrometer, was changed, or in other words the current was sent through the galvanometer in an opposite direction, but it still indicated a current [[underlined]] adverse [[underlined]] to that of the battery discharge. [[end page]] [[start page]] Thursday Oct 19th 1843 [[vertical squiggly line]] 77 Made today an apparatus for for getting the perforation in a paper more conveniently a + b are two glass tubes supporting [[image of apparatus]] two corks through which a needles are passed. By sewing the needles more or less through the corks and by elevating one of them, the adjustment can be readily made. Also prepared two [[circled]] webs [[/circled]] of wires [[strikeout]] for [[/strikeout]] to serve as coiles, with them and others like them, I intend to repeat [[image of web]] the experiments on successive induction from the Leyden jar. [[line drawn across paper]] Friday Oct 20th Repeated the experiment of Matteucci in [[referen?]] to obtaining the current by means of a galvanometer. found the result the same as given in his paper. Repeated this exp with [[image of jar, wires and direction of current]] the same result. Three jars were used tolerably highly charged. When the experiment was first tried, and the jars highly charged, a spark quite loud was heard in the galvanometer. With a single jar, the discharge gave a current sometimes in one direction - and sometimes in the other.
78 Friday Oct 20th 1843 Repetition of Matteucci's Exp with galvanometer When [[underlined]] three [[/underlined]] jars were so charged that they did not produce a snap in the galvanometer, the needle remained unaffected. But when the charge was about 60 of the galvanometer, then a snap was heard in the galvanometer, and the needle was very visibly moved several degrees by a current in the [[underlined]] direction [[/underlined]] of the [[underlined]] primary [[/underlined]]. When the direction of the discharge was changed, in reference to the conductors, the result was still the same. When the snap ^did not appear in the galvanometer, then the needle was affected with a mere tremulous motion. [[underlined]] One Small [[/underlined]] jar charged with [[underlined]] 10 s/l [[/underlined]] of the unit jar, the needle moved 3 or 4 degrees current [[underlined]] direct [[/underlined]].[[underlined]] Snap in galvanometer [[/underlined]]. 3 jars charged with 10 s/l of the unit jar, no spark ---- [[underlined]] direct [[/underlined]] 4 [[degree symbol]]. [[+ in margin and a vertical line next to the next 4 entries]] 3 Jars Charge 20 s/l - no spark [[underlined]] adverse[[/underlined]] 3 Jars Charge 15 - no spark [[underlined]] direct [[/underlined]] 3 Jars charge 25 - " " no motion 3 Jars charge 30 a spark Direct 5[[degree symbol]] [[line across page]] [[+ in margin]] N B In this series, the shock might have, and probably did cut across in some cases either wholy or in part. [[end page]] [[Start page]] Friday Oct 20th 1843 Repetition of Matteucci's exp with the galvanometer 79 3 Jars charge of unit jar " " " 5 no spark in galvanometer [[underline]] no effect [[/underline]] " " " " 10 " [[underlined]] direct [[/underlined]] " " " " 15 " adverse " " " " 20 " adverse " " " " 25 spark adverse " " " " 30 " low spark [[underlined]] direct [[/underlined]] [[the next chart contained in a box]] 3 Jars change of unit jar in 0 " " " " " 5 No snap in galvanometer 0 " " " " " 10 0 " " " " " 15 Do Direct strong " " " " " 20 Do Adverse " " " " " 25 Do Adverse " " " " " 30 Snap Adverse strong " " " " " 35 Snap Adverse " " " " " 40 strong snap Direct strong " " " " " 45 Loud spark Direct feeble " " " " " 50 " Do Adverse feeble See bottom of page 91 From the above series of results, it is evident that the changes in the direction of the galvanometer are as great as with the magnetization of steel needle, and hence the results obtained by Matteucci the Italian, are not to be considered as absolutely ----- All these results are in conformity with the supposition that the reduced current is not a simple disturbance of the electricity of the wire in a surge discharge, but that it consists [[end page]]
80 Friday Oct 20th 1843 [[line wavy]] The secondary current may be represented by a wave in reference to its axis thus: [[image of drawing]] the beginning induction of the discharge of the jar will give an intense current which will be of very short duration. the end ^[[insert]] ing [[insert]] of the jar current will give a wave in the + direction, but since the ending takes place more gradually the than the beging, the wave will not be so intense. Again the rebound of the jar current will produce anothe wave adverse to itself, and hence in the + direction, and the stoppage of this another in the same direction with itself, and hence adverse to the primary wave, and there minus, this is represented by [[underlined]] a [[/underlined]], the others by [[underlined]] c [[/underlined]] [[underlined]] b [[/underlined]] and [[underlined]] e [[/underlined]]. The next rebound will produce an other which will again be on the same side with the first induced current and so on. The fact that more than one hole is piered in card, is mentioned by Mr Etrick, Annules of Electity,vol 2, x 3g. [[end page]] [[start page]] Monday 23rd 1843 [[squiggly line]] Exper. on the holes pierced in cards by the secondary current 81 Commenced this morning the Repetition of Matteucci's experiments, to determine the direction of the induced current by means of the pierced card. + - The points were placed 1/4 of an inch apart, with one jar, charge 60 [[strikeout]] three [[/strikeout]] two small holes near the - minus point, current adverse. + - charge 80, [[underlined]] three [[/underlined]] holes nearer the minus pole. The larger hole was ragged; one jar, distance same + - charge 90. Distance same, [[underlined]] three [[/underlined]] holes nearer the minus side. When these holes are examined with a magnifying glass, the larger appears ragged and triangular. + - All things remaining about the same with the same charge, a large irregular hole was formed nearer the - minus end. + - Small charge elect 30 [[degree symbol]], hole near the minus side. + - Distance 1/2 an inch, single hole near the [[underlined]] minus [[/underlined]] pole. At this distance, a brilliant spark appeared between the points of the needle. __ When the points were removed to a greater distance, so that the spark could not pass, a singular hollow sound was produced as if the discharge from the battery met with an interruption. + + Distance rather more than 1/2 an inch. One hole of a ragged appearance near the minus pole. NB all the larger holes appear double and sometimes triangular.
Monday Oct. 23rd 1843 Pierced card with 2nd current common elect In repeating the forgoing experiments, the position of the points must be attended to. If they have relative to the paper, the position shown in the figure. The whole is made as [[underline]]a[[/underline]] opposite the negative points, but near the + points. [[drawing of a upward curved line in between a point labeled positive and a point labeled negative. There is a point labeled "a" on the upward curve closer to the positive point.]] [[drawing of an inverted slight sin curve in between a point labeled positive and a point labeled negative with a point labeled "a" lying directly in the middle on the line.]] When the paper occupies the position shown in the figure, the hole is mid way between the two points. Mr Matteucci says that if the two points are farther separated than from 3 to 6 millimetres, or from about an 8th to the [[underline]]quarter[[/underline]] of an inch, the hole is no longer found as the negative end, but near the middle, as if we had made the experiment in rarified air. The results obtained by the Italian was probably due to the position of the paper. Repeated the last experiment with the same result, the hole was mid way. [[drawing of a positive sign with a circled dot above it. Next to that is a negative sign with two plain dots above it.]] Repeated the exp with the paper touching the needlepoint on the two sides, hole single but ragged on the [[underline]]minus side[[/underline]]. [[drawing of a positive sign (+) and negative sign (-) with bold lines above each, separated by a downward sloping diagonal line]] In these experiments , the paper was placed thus: [[drawing featuring a positive sign (+) with a dot above, next to it a negative sign (-) with three dots above.]] Dist [[underline]]one[[/underline]]eight, 3 holes near the minus end. [[Drawing featuring a circled dot, next to it a plain dot, and next to that, three dots increasing in size as they rise from bottom to the top meeting the end of a negative sign (-)]] Distance the same, 4 holes were made, one and the largest directly at the points],two below this point, and one mid way between, Elect 70⁰. [[Drawing featuring a line of three dots with a demarcation between the second and third dot]]Distance same , charge 30⁰, one ragged hole near [[underline]]minus[[/underlined]] point. [[drawing of a dot, x, dot]]Distance 1/20 of an inch, charge high, ^70⁰ ragged hole in the middle. [[End Page]] [[Start Page]] Monday 23 1843 Card pierced with 2nd current Common Elect. 83 [[drawing of three dots in horizontal line]] Distance 1/20 of an inch charge feeble 30 [[strikethrough]]three[[/strikethrough]] [[strikethrough]] one [[/strikethrough]]large hole[[strikethrough]]s[[/strikethrough]] largest near the + pole. [[drawing of a plus sign (+) with two dots over it and a dot to the right of the plus sign]] Distance same small charge one hole near plus point. [[drawing of plus sign beneath an open circle, colon, dot in between, open circle with a line underneath.]] [[Note in left margin]] One jar used in all these experiments [[/End of left margin note]] [[There are drawings to the left of each of the following entries]] Distance same 1/20 charge 20˚ three fine hole, near negative pole. " " " charge 30 one hole mid way " " " charge 20˚ one fine hole mid way " " " " 30 3 holes as per fig. " " " " 40 2 holes " " " " " " " " 60 single ragged hole " " " " " " " " 65 large [[drawing of a square]] triangular hole near the middle inclined to one side " " " " 70 two small holes [[Line drawn horizontally across page]] Experiments continued with 3 jars instead of [[underline]] one [[/underline]] [[There are drawings to the left of each of the following entries]] Dist 1/20 of an inch charge 10˚ two large holes at - point " " " 20˚ three holes near + pole " " " 25 three holes as in figure " " " 30 two holes " " " " " " 40 4 holes " " " " " " 60 One large irregular hole near the negative pole " " " 4˚ one hole " " " 5˚ one hole mid way " " " 6˚ two holes [[End of Page]]
84. Monday Oct 23 1843 Exp continued with 3 jars Distance 8/40th = 1/5 Charge 10º 3 holes as in the figure 11º 2 holes as in figure 20 one large irregular hole at the -po 30 one small hole as in fig. 35 one large irregular hole as in fig. 40 single hole at negative pole 50 three holes near negative pole 60 one large hole near the middle --- charge with 3 jars distance 17/40th of an inch charge 10º one hole ˄[[large]] near minus pole 20º Do do Do do 30º two small holes near - pole 40º one hole middle little [[circled]]near[[/circled]] - 50º two holes at minus pole 60º one hole at the minus pole 60º one large 2 small holes at minus pole --- In all the last experiments with the 3 jars, except one, the hole has been nearer the [[underline]] minus [[/underline]] pole. --- In making the foregoing experiments, I observed that when the wire of the secondary current came in contact with my leg at the time of the discharge, a spark was given off which produced a prickling sensation, with this, an electrometer might be charged. [[end page]] [[start page]] 85 Monday Oct 23. 1843 Experiments with the Franklin battery Charge 20 snaps of unit jar no perforation at the distance of 4/40 = 1/10 of an inch [figures in left margin like plus signs, dots and minus signs] 40 snaps one hole near plus side 50 snaps . Elect 4 Double hole in the middle 60 snps " 10 one large hole two small near + 70 " " 14 one hole middle 20° Four holes from point to point 25 large hole near plus --- Distance 1/5 of an inch Frank battery Electrometer 10° one hole near minus 20° three holes nearer the minus 30 one large hole two small near the minus 40 one large hole at minus All these results give holes near the minus pole --- [[margin]]One jar charged each time to 90°[[/margin]] Experiments with primary current Passed spark from the machine through paper between two needle points the perforation was very minute and directly opposite the [[underlined]] minus [[/underlined]] point Sent charge of one jar Elect 90 through paper perforation near [[strikethrough]] the needle and [[/strikethrough]] at one [[underlined]] minus [[/underlined]] two holes very fine compared with those of the secondary discharge - the paper was different. Repeated the same with other paper - one hole & larger near the minus pole Same distance in all these experiments 3/8 of an inch one hole near minus side Distance increased one hole at minus 5/8 of an inch
86 Monday & Tuesday Oct 23,24 - 1843 Exp. with Pierced and Primary Current [[Diagram]] Distance diminished to 1/8th of an inch, 2 holes [[underlined]]minus[[/underlined]]. [[Diagram]] Distance 1/10th of an inch. This gave a very beautiful result, four perforations each smaller than the other. The largest near or at the minus end, the nex at the middle, the third a little farther away and the third at the plus end. [[Diagram]] Distance 1/15 of an inch, 2 holes at plus, one at minus, holes at plus ragged as if by several discharges. [[Diagram]] Distance 1/10th of an inch, two holes, one near the minus end, the other near the middle. In all these experiments with the primary current, the perforation was no larger than with the secondary current. Exp. with smaller charge, points about 1/15th, one jar charged to [[Diagram]]30⁰ one fine hole at minus end. [[Diagram]]30 two holes near minus. [[Diagram]]20 two holes together near the middle. [[Diagram]]20 near the minus, one hole. Tuesday [[image of experimental device]] Sent shock from single jar through a thick card on the [[?]] apparatus with blunt points, which were about 3/4 of an inch apart, [[underlined]]three[[/underlined]] holes were made about one third way from the minus pole as in the figure. The points were next removed to the distance of an inch, one hole at the minus pole. Repeated the same, one hole at minus pole, distance of points 1/2 an inch. In these exp, the jar was charged to 90⁰, but it was cold. [[End Page]] [[Start Page]] Tuesday Oct 24th 1843 Experiments with the pierced card Primary current 87 [[Note in right margin]] Thick paper [[/End margin note]] one jar Repeated same one hole at minus Do " " " " " Do " " " " " Do with elect at 40⁰ points near 2 holes Repeated same in all respects one hole at minus Points 1/4 of an inch apart one jar Charge of elect 20⁰[[Diagram]] one hole at minus pole 25 [[Diagram]] Do do near do 40 [[Diagram]] Do do do do do 50 [[Diagram]] two do do do do 60 [[Diagram]] one do do do do 70 [[Diagram]] one do at the plus pole 80 [[Diagram]] one do at " minus pole 90 [[Diagram]] one do " " " " [[Right margin note]] Thick paper [[/End Margin Note]] Points one inch apart [[underlined]]one jar[[/underlined]] Charge elec 20 did not pass 40 do "" " + + 50[[Diagram]] one hole near minus pole 60[[Diagram]] " " " " " little farther from pole 70[[Diagram]] " " " " " 80[[Diagram]] one hole at minus pole 85[[Diagram]] four holes near each other and the [[underlined]]minus[[/underlined]] pole 90[[Diagram]] six holes as in the figure + - Points same distance 3 jars [[underlined]]Charge elect[[/underlined]] 40[[Diagram]] one hole near the minus pole 50[[Diagram]] " " " " " " 60[[Diagram]] two holes near minus pole 70[[Diagram]] two holes " " " 80[[Diagram]] " " " " " [[Right Margin Note]] Thick paper [[/End Margin Note]] 80 was about as high as I could charge three jars.
88 Tuesday oct 24th 1843 [[vertical squiggle line]] Experiments with pierced card by the primary current Repeated the experiment with one jar and distance one inch with thin paper the following is the result charge by elect. 50[[Diagram]] one hole at minus point 60[[Diagram]] one hole near " " 70[[Diagram]] one hole at " " 80[[Diagram]] two holes nearer " " 85[[Diagram]] one hole near " " 90[[Diagram]] two large holes and several small ones [[right margin note]] thin paper [[end note]] The general result of this set of experiments, is the same as that of the thick paper on the last page. [[line across the page]] Next made a series of experiments with fine sewing needle points. [[underlined]] One jar.[[/underlined]] First the distance apart is one inch, perhaps a little more. The charge was from 40 to 90 with the same result, the perforations were all at the minus pole, and single with one exception, the hole with the charge of 80 was double, but near the [[underlined]] minus [[/underlined]] pole. Next the points were 1/4 of an inch apart charge by the electrom. 20[[Diagram]] one hole near minus pole 40[[Diagram]] three " " " " 50[[Diagram]] one " " " " 60[[Diagram]] " " " " " 70[[Diagram]] three holes one in the middle two near minus pole 80[[Diagram]] two holes near minus pole are very small 85[[Diagram]] one " " " " 75[[Diagram]] five holes across the whole space [[Left Margin Note]] Fine needle points [[/End Margin Note]] When several holes were thus made, it appeared that the discharge took place [[underlined]] in parts [[/underlined]], and not in a single discharge. [[Bracket]] For other exp. on this point, see page 129 [[End Bracket]] [[end page]] [[start page]] Tuesday oct 24th 1843 [[vertical squiggle line]] Exp with pierced card primary current 89 Made a series of experiments on the suggestion from the remark at the bottom of the last page, with the spark from the prime conductor. The holes were generally single, and always at the minus pole, although the sparks were double and stable. The fact that a hole previously existed did not interfere with a new hole, since when a hole was perforated at the [[underlined]] plus [[/underlined]] pole an other was made at the [[underlined]] minus [[/underlined]], as if the first did not exist. [[underlined]]Wednesday[[/underlined]] To test the last experiment's result still, the jar was so arranged with a conductor [[image]] with a rounded end as to discharge itself when the intensity arose to a given height. The results however with this, were about the same as with the other arrangement. The paper was pierced sometimes with a single hole sometimes with two and more. When the interval at [[underlined]] a [[/underlined]] was 3/4 of an inch, and the points 3/4 also the perforation as at the negative pole and single, but when the points were brought within 1/5 of an inch, all the perforations were double and some of them [[?]] apart. Repeated last exp, distances same,- found [[underlined]] three holes [[/underlined]] produced twice, and one larger hole, one all near the negative end. From these results, it does not appear that the repeated discharges which I suspected might have some influence in producing the holes as much effect. The weather is not very favourable for elect exp. today, the wind is now southerly!
90 Wednesday Oct 25th 1843 [[squiggly bracket]] Pierced card with 2nd current Repeated the exp with pierced card, and the secondary current with the self discharging apparatus described on the last page. Thick pan needepoints 1/10 of an inch apart, distance of 3/8 of an inch. Results as follows: 7 holes perforated as the [[underlined]] minus [[/underlined]] pole and single. 2 singles near the middle. 4 double holes, 2 near the [[underlined]] plus [[/underlined]] pole, 2 with one at each pole. [[line across page]] Dist 14/40 = 7/20 of an inch the balls. The points 3/40 =1/13 of an inch. 1 one hole near the negative. 2 two holes one at negative small one near middle. 3 three holes near middle nearer plus pole. 4 two holes on a line mid way. 5 two holes " " " " ". 6 one hole at negative pole. [[line across page with illegible writing]] These results are similar to those obtained Monday 23 inst. [[NB written in left margin]] I observed a fact of some importance in these experiments, that although the spark did not pass through a hole which was pierced near the card at the plus pole, yet it passed a considerable distance out of its course to go through a hole near the minus end. Thus + & - [[image of symbols]] representing the points, and [[underlined]] a [[/underlined]] the hole, the discharge passed through [[underlined]] a [[/underlined]] rather than perforate a new hole - this shows the influence of the perforation of one current in determining that of the other.. [[end page]] [[start page]] Wednesday Oct 25 1843 [[squiggly line]] Tertiary current [[squiggly line]] secondary current with galvanometer 91 In one of the last experiments, when from the sound of the discharge it appeared evident that the electricity cut across from one part of the primary conductor to the other, the perforation was in the middle and not at the negative end. [[line across paper]] [[images of drawings]] Made an arrangement for the current of the [[underlined]]third [[\underlined]] order, - when the two ends of the conductor of the third order were placed near each other, a spark was produced 1/4 of an inch long with the mere snaps of the machine and without the jar. The perforations in the paper placed at [[underlined]] a [[/underlined]] were on the negative side, occasionally three very fine holes were made near the same pole, but this was by a succession of sparks. Placed the apparatus of the pierced card in the circuit of the Secondary current, and then three sparks in the conductor without the jar. The points were 1/20 of an inch apart. The perforation was generally near the negative side, but sometimes and often, near the middle inclining to the negative side. The spark appeared on one case to be double, but in general but one hole was perforated by a single spark. [[line across page]] Matteucci's experiments with the galvanometer were made with the battery. To make parallel exps the Franklin battery was charged as follows: charge per elect. 10˚ secondary current per galvanometer adverse - 12˚ " " " " direct 20˚ " " " " direct + 30˚ " " " " adverse - 40˚ " " " " direct + with the last a loud snap
Wednesday Oct 25th 1843 Magnetism of Needles by the Primary Current The motion of the galvanometer in these experiments was as if it were acted upon by more than one current charged the battery to 30º current [[underlined]] Direct [[/underlined]] Made various attempts this afternoon to get a reversal of the poles of a needle by the direct discharge but did not succeed. First sent charge from Franklin battery through copper bell wire about 18 inches long. Needles placed at different altitudes above, from contact to one inch, all magnetized +. The needles were small No 9. [[image- sketch wire wrapped wax block]] Next wrapped long piece of thin wire around a block of bees' wax, placed needle transversely, sent through charge from single jar, needle always magnetized +. The needles in the case of a single jar, highly charged, were more highly magnetized than with the battery in the experiment with a straight wire. Thursday [[margin note]] Needles no 12 [[/margin note]] Repeated the last exp with the battery charged to 60°. The needles were all magnetized [[underlined]] plus[[/underlined]], except the one nearest the wires, which was about one tenth of an inch distance, this was magnetized scarcely at all. Repeated same battery charge 45° [[margin note]] Needles no 12 [[/margin note]] Needles distance from wire Deflect 1 1/10 of an inch 0 2 .2 0 3 .3 -0 4 .4 +5° 5 .5 +15 6 .6 +19° 7 1.0 +17° [[end page]] [[start page]] Thursday Oct 26th 1843 Magnetization of Needles by the primary current 93 From the last experiment, it is evident that the feeble magnetism of the needles as given vol 2, p 271, 272, [[?]] is not due to position of the wire being confined to the middle of the needle, since in this case it is under the whole length, and yet the needle is not at all magnetized, or in the adverse direction. [[margin note]] used in this exp [[/margin note]] [[Box is drawn around the following table, with an asterisk to the right of the box]] [[margin note]] needles no 12 [[/margin note]] Repeated Battery charge 60° Needles distance Deflect 1 .1 of an inch 0 2 .2 0 3 .3 0 4 .4 +2° 5 .5 +15° [/end of box]] [[underlined]] NB [[/underlined]] In these experiments, care was taken to place the needles at right angles to the magnetic meridian, so that no influence from the earth might affect the result. [[margin note]] same coil around beeswax [[/margin note]] Needles with temper drawn to bluness Battery 60° [[margin note]] Needles No 12 temper blue[[/margin note]] Needles distance Deflect 1 .1th of an inch 0 2 .8 0 3 .4 1/2 +13° 4 .6 +18° 5 .7 1/2 +18° 6 .9 +19° The softness of the needle gives it a more intense magnetism. [[Line drawn across page]] * Made some very small needles from the hair spring of a watch, arranged three of these above each other at the distance of 1/8 of an inch. Needles distance Deflect Small [compass?] 1 1/8 +5° 2 1/4 0° 3 3/8 -1°
94 Thursday Oct 26th 1843 { Magnetization of Needles by primary current } In the last experiment, the result was a little doubtful, because the needles were slightly magnetic by cutting of the length from the spool of steel wire. Repeated the same, great care being taken to demagnetize the needles, the result was as follows: [[/margin]] * wire curled around bees wax. [[/margin]] Battery 45[[degree symbol]] [[Chart]] Wire Needles Needles distance Deflect 1 1/8 of an inch 0 2 " 1/4 " -5 3 1/2 +slightly Small Compass [[/chart]] Battery 45 [[degree symbol]] [[Chart]] Needles no 11 over coil around bees wax Needles distance Defl. 1 1/7 of an inch -2 [[underline]] minus [[/underlined]] 2 2/7 -0 3 3/7 +17 4 4/7 +19 5 5/7 + 1/2 23 6 6/7 +22 1/2 7 7/7 +22 8 8/7 +20 9 9/7 +17 1/2 10 10/7 +17 11 11/7 +14 Larger Compass [[/Chart]] [[Chart]] Needles no 11 Battery 45 Needles distance Defl 1 1/8 -1/2 [[underlined]] Minus [[/underlined]] 2 1/4 +3 3 3/8 +14 4 1/2 +20 [[/Chart]] [[end page]] [[start page]] Thursday Oct 26th 1843 { Magnetization of Needles by primary current } 95 Battery 48˚ [[Chart]] Needles no 11 Needles dist Defl 1 1/8 0 2 1/4 -1/2 minus 3 3/8 +20 4 5/8 +22 5 6/8 +25 6 1 1/8 +24 [[/Chart]] Large globe placed on the end of the wire, or rather I should say, introduced into the circuit, on the side next the positive poles. [[Line drawn across page]] It is evident from the foregoing experiments, on the magnetization of needles, that by increasing the number of wires the charge of polarity may be produced in larger needles, and this result is what I expected in making the arrangements. In this arrangement however, the diminution of force and change of direction is probably influenced by the currents in the spires on the under side of the bee's-wax. [[Double line drawn across page]] Evening, 8 o'clock. I made some experiments tonight on the electrical light. The discharge through a vacuum is continuous and larger in the middle, but when small sparks were pass, beams of electricity diverged in all directions towards the glass, and particularly when the hand was brought near, and this is undoubtedly owing to the lateral induction of the hand--when a negative conductor is placed at a little distance from a positive one, the induction is principally directed to the negative, but all the distant objects around allso receive the induction, so that the sum of the negative and the positive electricities is the same.
96 Oct. Thursday 26 1843 The negative conductor has however less negative electricity than is equal to the positive in the other, on account of the distance, but the remainder is made up by the induction of the other bodies in the room around, but at a distance. The two electrics must be equals, for the same reason that the attraction of gravitation may be said to be the same at all distances, when we consider the increasing spherecal surface which surrounds the attracting body. [[margin note]] See page 184 [[/margin note]] When the two bodies are near to each other, they act on the distant bodies as one, and tend to neutralize each other. From this consideration, we may perhaps get a more intimate acquaintance with the phenomenon which is exhibited by electrical light in a vacuum. I noticed one fact, which I have not seen described, [[underlined]] viz [[/underlined]], spots of light in the beams of electricity, as they were given off from the upper ball, they were about a fourth of the distance (6 inches) downwards. I also passed the secondary spark through the vacuum, and observed that it produced the same coloured appearance as the ordinary spark. The experiments I have made this evening have a bearing on the [[word circled]] speed [[/word circled]] of electricity in passing along a wire. See page 54 -- Friday, rain, weather unfavourable for elect exp. [[end page]] [[start page]] Saturday 28th 1843 97 We cannot explain all the phenomena of electricity, I think without admitting the existance of a plenum of an ethereal medium, the atoms of which repel each other and are possessed of inertia. When a Leyden jar is grasped by the hand, and a spark from a long conductor is thrown on it, the induction takes place with such intensity as to give a very unpleasant shock to the hand. When the outside of the jar is connected with an insulated ball, the jar being also insulated at the moment the jar receives a spark, the electricity is propelled from the outside of the jar to the connected insulated ball and immediately afterward a return wave is produced, which may be exhibited by the effect produced on the needles of the two sets of spirals. The equilibrium in this experiment is evidently produced by a series of oscillations. The return wave is not as strong as the direct wave, and when the wire conveying the wave to and from the jar is connected with the earth, instead of the insulated ball, the needle is always magnetized by a current from the jar. The return wave should perhaps be increased on the direct waves, diminished by the [[?]] of repulsion of the end of the conductor at the moment of the discharge, but this is not [[image of drawing]] sufficient to neutralize the current, particularly when it is drawn from the outside of the jar near the bottom. The fact of the evolution of oxygen and hydrogen from both poles of the decomposing apparatus, in case of ordinary elect. noticed by Waloston, is probably due to the oscillations.
98 Saturday Oct 28th 1843 My attention had particularly drawn to the subject of the last page from having seen last night, the letter of Dr Faraday to the Secretary of the East India House, on the question of defending the powder houses of India from thunder -. The Dr does not think that there is any danger from the induction of a rod near the house, but he appears to have no idea of the induction produced by a conductor at the the moment it is connecting a discharge, which I have discovered. [See page 65 of this vol.] The effects I have described as witnessed in the case of Pres Hamiltons House, are of this kind, and yesterday I found in the Comptes Rendus for Aug 9th 1843, an account of the steeple of the Strasbourgh cathedral being struck, and at the moment of the flash, every part of the shop of a tin man situated near the foot of the rod, or rather where the rod entered a fish well, was illuminated by spark of electricity, athough no thunder was heard. [[drawing]] In the paper of Dr Faraday (for an abstract of which, see common place book), an account is given of some experiments on lateral discharge one of which consists in throwing sparks on a thick wire C W [[refers to drawing]], aside of which a wire is placed 10 or 12 feet long an induced or rather lateral spark is seen at [[underlined]] a [[/underlined]] and [[underlined]] b [[/underlined]], and this is a fine illustration of the fact that I have been contending, for that one part of the wire is + (plus) to the other. [[End Page]] [[Start Page]] 99 [[Note in left margin]] Conjecture proved true pg 158 [[/End note]] The nature of the sparks at [[underlined]] a [[/underlined]] and [[underlined]] b [[/underlined]] in the experiment of the bottom of the last page, ought to be examined, is is probably a double one. There is also some objection to the experiment, as giving a double result, since the primary current would produce in the lateral wire as it is placed in the figure, an induced current, or rather two induced currents. [[Note in left margin]] Needles No 10 [[/End Note]] [[Note in right margin]] Magnetization of needles by the battery discharge [[/End Note]]Battery charged to 48˚ Needles distance defl 1 1/8 34 2 1/4 31 3 3/8 27 4 1/2 25 5 5/8 24 6 6/8 21 7 7/8 22 8 1 23 9 1 1/8 24 10 1 1/4 23 11 1 3/8 23 12 1 1/2 22 13 1 5/8 20 14 1 3/4 22˚ [[Right margin note]] NB in the case of a needle placed on the ribband in an other exp of same charge the def was 36. [[/End note]] In this experiment, instead of a single wire the discharge was passed through a copper ribbon 1 1/2 of an inch in width, and 2 feet long. [[Left margin note]] 1/2 Needles No 10 [[/End Note]] Needles Dist. defl. Middle 1 on 23 [[bracket to the right of this line and the next]] 21 1/2 [[/End bracket]] Middle 2 " 20 [[bracket to the right of this line and the next 3 lines]] 21 3/4 [[/End bracket]] N Side 3 " 22 N Side 4 " 22 S Side 5 " 23 S Side 6 " 20 See top of next page
[[start page]] [[top margin]] 100 Saturday Oct 28th 1843[[/top margin]] In the last experiment, several half needles were placed on different sides, and in the middle of the copper riband, in order to ascertain if there was any difference in the magnetizing power of the plate at the edges, and in the middle. The result would appear to give a greater intensity at the sides, but the difference is not sufficiently great to render it certain that such a result was to be depended on. The induction at a distance, which produces the changes in the small needles, would interfere with this result. [[line across width of page]] [[A figure takes up much of the bottom half of the page. It appears to have been drawn with the page turned sideways, with writing down the left and right margins, corresponding to the top and the bottom of the figure, respectively.]] [[sideways along left margin]]Large needles no 2 broken into two pieces[[/sideways along left margin]] [[sideways along right margin]] Battery charged to 48˚ All magnetized [[underline]]plus[[/underline]][[/sideways along right margin]] [[Drawing]] In the above drawing, the position of a number of half needles no 2 are shown as they were placed on the surface of the tin foil, on the coated pane of glass called the square of Franklin. [[end page]] [[start page]] [[top margin]]Saturday Oct 28th 1843 101[[/top margin]] Every needle on the tin foil was magnetized. The irregularity is due in part to the different magnetic capacity of the needles, some of them were shorter than others, as it was impossible to break them all of the same length. Also the tempre of the whole lot was not quite the same, since some of them could be bent much more than others. The numbers annexed to each needle indicates the deflection or relative magnetic intensity of each, and from there it will be seen that the electrical action extended to every part of the tin foil. This experiment is interesting, and must be varied in reference to the thickness of the sheet, also by seperating it into parallel sheets to acertain what part of the effect is due to the magnetization at a distance from the discharge. NB One result deserves particular notice, all the needles were magnetized by a [[underline]]plus action[[/underline]] [[line across page width]] [[A figure takes up much of the remaining page. It appears to have been drawn with the page turned sideways, and writing along the left and right margins, corresponding to the top and bottom of the figure, respectively.]] [[sideways along left margin]]half-needles no 11[[/sideways along left margin]] [[sideways along right margin]]Battery charge 48˚[[/sideways along right margin]] [[left margin]][[thickened X]]poles[[/left margin]] [[caption beneath figure]]The numbers indicate the deflection[[/caption]] Repeated the last exp. with smaller needles, also broken in two, but the parts were nearer alike and the tempres more ^[[nearly]] equal. [[notation in bottom right corner]]X extend around the hole! Have done So. p 180[[/notation]] [[end page]]
102 The experiment on the last page must be repeated with other neidles [[?]] and with the tin foil separated also with thick plate A.P.S. 3 Nov. 1843. Referred to the Comm. to whom the former papers of Prof. Henry were referred, viz. Dr. Patterson Examina therefore[[?]] Prof. Bache, Nov 4/43 A.D.Bache Mr. Lakinse [[?]] J.K.K. Four.[[?]] [[end page]] [[start page]] 103 [[image - drawing]] [[image - drawing]] In this arrangement, the return or rebound takes place in [[underline]]a[[/underline]] [[underline]]b[[/underline]] instead of in the conductor. See page 57 of this vol.
[[start page]] 104 Jany 2nd 1844 Observed to day a fact in reference to the drop of water on a hot iron which is some importance. A quantity of water was thrown on the top plate of an air tight sheet iron stove, a considerable sized dopule of this remained for several minutes in motion on the top of the iron. When the eye was brought down so as to be on the opposite side of the drop from a window, the light could be seen between the underside of the drop, the water was not in contact with the iron, but when the metal was so much cooled as to produce the explosive production of steam, the drop was seen at the moment of hissing to touch the metal. Jany 18th Repeated to day Dr. Faraday's exp given in the Philosophical magazine, vol 22 200p, on the induction through different vessels. [[image]] A large was kettle was placed on a cake of bees wax, and the out side of it was connected with an electrometer with gold leaves. A ball b was then let down into the kettle by means of a fine silk thread. The leaves instantly diverged and remained at the same angle, what ever position the ball b occupied within the kettle. It also remained the same agreeably to the account given by Dr Faraday when the ball was touched to the inside of the vessel. This experiment appears to me to be in strict accordance with the mathematical theory of elect. that the induction should be the same in total amount at what ever distance the surface of the circumscribing sphere is from the balls, is a consequence of the repulsion being inversely as the square of the distance, and the fact that the surface of the ball increases as the square of the same distance. [[end page]] [[start page]] Jany 18th 1844 105 I was enabled to make some variations in the experiment which is also in accordance with, and was suggested by this theory . When the outside of the globe, or rather bottle, was touched while the ball was inside, the leaves collapsed, because the unsaturated matter in the surface just balanced by its attraction the repulsion of the electricity in the ball. The condition [[image]] of the whole is shown by the figure in the margin. When the ball was withdrawn, the leaves then diverged with - elect! This effect was owing to the repulsion of the ball being withdrawn, and then the unsaturated matter of the globe drew into itself, the electricity of the electrometer and the leaves consequently diverged with negative electricity. [[image]] I next next removed the knob and inner wire of a jar, charged the same plus intensely, then insulated it on a cake of wax, touched the outside, then let down into the interior a carrying ball, but no signs of electricity could be perceived, neither side was in excess. The larger dimentions of the outer coating just made up for the thickness of the glass, so that in the arrangement of a jar without a knob, there is no excess of elect., and hence it would seem to follow that with the same amount of internal surface of coating, the same charge can be given to a jar without a knob whatever be its thickness. The globular form of a jar enables it to retain its electricity much better, but also to receive a greater charge. Dr. Robeson has some remarks on this point, Mechanical Phil., vol 4, page 131, also some remarks on the lateral explosion may be found at page 172 of the same.
106 Jany 19th 1844 I gave a lecture today on Dynamic induction, and in the course made the following attempt to explain the fact of the lateral currents or those produced in lateral adjacent wires. [[image - a diagram illustrating the following description]] In the moment the spark passes into the wire [[underline]]a[[/underline]], the fluid in it will be thrown into the condition as marked by the the [[?]] +, and minus. The natural electricity will be drawn to the farther end by the [[?]] elect of the jar as it is entering the upper part of the wire, and at the same moment, a part of the interior repulsion of the jar is removed by the rushing of the electricity to to knob, therefore, as I have before said, the wire will assume the condition [[crossed out]][[/crossed out]] shown in the figure. The effect that this will have on the adjacent wire, is readily seen, the upper end will become plus, and the lower minus, or the effect of a current from the lower to the upper end will be experienced. In the next moment, the electricity of the jar will pass to the outside through the wire, and the natural state will be restored with perhaps an effect something like a momentum, a current in the opposite direction will then be the result in the adjacent wire. The effect of this induction is perceived as so great a distance, that I cannot for a moment think that the effect is the result of mere [[strikeout]] repulsion acting at a distance, but from all analogy, I would contend that the result is produced by a wave motion communicated from atom to atom of the etherial medium, and this is the case of the intervening medium being air, would give rise to a progressive polarization of the particles. Perhaps this will be rendered more clear by the following figure: [[end page]] [[start page]] [[image]] 107 Let [[underline]]a b [[/underline]] be a row of etherial attoms extending in space [[strikeout]] from one wire to the other, then if the wire [[underline]]a [[/underline]] becomes polar as a whole, the atom [[underline]]a [[/underline]] will be attracted, and this will give motion to [[underline]]b[[/underline]] in the same direction, and then to the next, and so on to the last, which will [[strikethough]]rush to?[[/strikethrough]] and the electricity, will rush from the rod or will be drawn up in the rod to supply the tendancy to a vacuum, while the electricity in the lower end will be drawn up the rod by the increase of the pressure at the lower end. If an [[?]] the atoms in succession will be thrown in a polar state for an instant, and the [[force?]] will be transmitted wave pushing from one wave to the other. The effect will only be instantaneous. When the primary wave returns to its natural state, the reverse [[motion?]] will take place. To explain the phenomena of galvanic induction, the conducting wire may be considered as during all the time of discharge in a state of polarization as a whole. [[image of drawing]] Consequently when a second wire is brought up to it, induction is produced so as to produce a current in a definite direction. Also when the wire returns to its natrual condition, a return current will be produced.
[[page start]] 108 March 6th 1844 [[line-vertical&wavy]] on the distribution of magneto elect, in passing through a quantity of water In my paper on induction no4, I stated that when the ends of the conducting wire of the magneto electrical machine were dipped into water, the shock could be felt in the fingers when they were plunged into the water, provided they were not placed at right angles to the line joining the wires and not too far behind the end of one wire I have thought since that this method of experimenting with the fingers in water could be employed with some sucess in determining the spread of electricity as it is passing through an unperfect conductor like water. For carrying this idea into practice, eight cups of Daniells battery were put in operation and connected with the magneto machine of Dr. Page. The [[wires?]] end, of the long wire were inserted into a basin of salt water, but with this, no effect was observable, the conduction of the liquid was so perfect that the current would not leave it to come up into the fingers. It would appear to follow the line of least resistance between the two poles of the apparatus. [[image--circle with four holes like button; the two larger holes on the horizontal axis with two lines drawn away from the center in a horizontal fashion]] Next the same poles terminated by two large balls, were placed in a basin of about a foot in diameter of pump water._ When the finger and thumb of the same hand were placed at [[underlined]] a b [[/underlined]], so as to be directly at right angles between the centres of the balls, no shock was felt, but when the fingers were a little moved so that the line going through was not ^[[moved]] more than 5˚ or 10˚ degrees from the first portion, a slight sensation was perceived, the small distance through which the line was burned in this experiment was surprising. [[page end]] [[page start]] March [[strikeout]] Feby [[/strikeout]] 6th 1844 [[line-vertical&wavy]] Distribution of elect. in passing through a quantity of water 109 Next a tub 22 inches in internal diameter was partially filled with water, the depth of which was nine inches. The poles or wires from the same machine were passed through the interior of two glass tubes, and cemented in this position so that no water could touch them. The ends of these wires were left projecting and these were plunged to different depths into the water and placed at different distances, as the experiments were varied. [[image]] The poles were terminated by two ball, and the two finger of the same hand were plunged into the water in the positions indicated by the letters a b c d and e ; and the shocks were found about equally strong in the four positions first designated,but it was rather stronger in the position represented by e, this however is probably due to the nearness of one of the fingers to the other pole. [[image]] When the poles were terminated by two plates of copper about 4 inches long, and an inch and a half wide, and these placed perpendicularly in the water, and in the positions indicated by the figure + and -, no shock was felt when the fingers were placed parallel to the plate as at a, but when they were placed at right angles as at b, then a powerful shock was felt. From this, it would appear that the electricity is given off at right angles to the plate on all sides. [[image]] When one pole was connected with a ball, the other communicated in a plate, the interior was as follows: a feeble, d + b nothing, e pretty strong, g strong, h strong.
March 14th, 1844 110 Distribution of a current of elect in passing through a quantity of water [[image]] When one finger of one hand was placed at a, and the other at b of the other hand, a shock was felt, and this continued to be perceptible until the distance 'a' and 'b' from the poles was 8 inches, while the poles themselves were 6 inches apart. [[image]] The poles being terminated as before, and the fingers placed at 'a' and 'b', the shock was quite perceptible, but it became much more intense when the finger 'b' was moved to the position b'. This might have been expected on account of the increased distance of the fingers. From all these results, it appears that the electricity tends to pass through the whole mass of the fluid and move along the line of least resistance. A number of experiments were made to determine if the current [[income?]] particularly sought the surface, but no satisfactory result was obtained. These results are all connected with the fact that the liquid was a bad conductor, and the fingers comparatively a good one. [[end page]] [[start page]] March 21st 1844 Capilarity the tenacity of water 111 Some children this morning were engaged in blowing soap bubbles, and while I was admiring the beauty of the colours exhibited, the thought crossed my mind that the tenacity of water might be determined approximately by means of them. This thought was suggested by the fact that a considerable weight of water could be accumulated on the lower side of the bubble without breaking the thin film. [[image]] By weighing the water, and knowing the diameter of the bubble, we can find the tension due to the weight per linear inch. In our observation the quantity of water supported was certainly more than a grain, and the colour of the bubble was violet in the upper part before the breaking took place. Now by inspecting the cable of the thickness of thin plates, as given by Newton we can find the thickness of the bubble of the violet color. The diameter of this bubble was about 3 inches, and the circumference about the pipe [[strikeout]] where the breaking took place about one inch. Suppose the quantity of water supported was two grains, then [[strikeout]] each linear inch of the circumference of the bubble at the pipe would support 2 grain and suppose it to be 2/1000000th of an inch in thickness, then one square inch would support 1,000000 grains, or nearly 4 lbs [[?]]. But this is not the only force the tenacity of the water is caused to balance. The bubble is distended by the condensation of the air by the mouth, and the expansion of the same in the bubble, and this must be added to the other, so that the tenacity of water is probably as great as that of ice. The only difference consists in the perfect mobility of the particles of the one, and the fixed mass of those of the other. It is probable that the soap diminishes the real tenacity of the atoms of water, while by rendering it less liquid, it increases the apparent tenacity.
112 In order to estimate the tenacity of the soap suds, the circumference of the larger part of the bubble should not be estimated, but that of the circle around which the observed colour is exhibited. Experiments should be made on the relative tenacity of soap suds and pure water by means of the balance and a disc of wood on the surface of the liquid. The bubble may be allowed to break of itself by the gradual running down of the water from its top towards the underside, and the colour which it exhibits at any one circle may then be noted. In this way the pressure of the air within may be avoided. [[note in margin on left side]] This cannot be [[\note in margin on left side]] That the weight suspended is supported by the circle of the bubble which is under consideration, will be evident from the consideration that a ribbon attached to the top and passed along the circumference of the globe would be equally tended through its whole length, if it were to be passed over pullies, but the air within which supports the ribands is without friction, and therefore each riband or rather [[?]] supports its share of the weight. It may be said that the weight suspended will apparently be increased by the weight of the upper part of the bubble, or by that of the part above the coloured ring. But the evaporization will lessen the weight as much as this quantity will increase it. Make experiments on pure water, and also distilled water with a solution of soap. I find that drops of water vary very much in sise with the form and size of the vessel from which they are let fall [[endpage]] [[startpage]] [[leftheader]]April 19th, 1844[[/leftheader]] [[rightheader]]113[[/rightheader]] Made to day a new series of experiments on soap bubbles. The soap used was the common rosin soap dissolved in rain water. The method of determining the tenacity of the bubble was as follows. [[IMAGE]] A bubble was blown on a ring of about half an inch in diameter by means of the bowl of a pipe, and the lower part brought into contact with the plate of [[/IMAGE]] the balance, to which it adhered, and on being drawn upwards it elongated into the form of a cylinder and drew up the scale pan. This cylinder became smaller at about e , and finally broke off at this point. The neck becoming less and less in diameter, and the thickness less and less as was evident from the exhibition of colours. In this way I succeeded in raising about four grains to the inch of the surface of the film, and allowing this just before it broke to be according to Newton's table of thin plates, (See Optics Brewsters, page 103) to be the one millionth of an inch thick, we will have a tenacity of 4 millions of grains in a session of such fillms an inch square in area. This will be nearly equal to 500[[strikethrough]0[[/strikethrough]] lbs avoir dupois per square inch. The above experiment gives us the tenacity of soap water to find the relative attraction of soap water and pure water. For this purpose we may use the method of the disc, drawn from the water or the method of the capillary tube, both will give the relative attraction. By both these methods, I find the attraction of pure water for itself greater than that of soap water. I find the ratio of the tenacity of the two waters is as 125:100. The attraction gave about 40 grains to the square inch, the glass disc was 2 inches in diameter. The tendency to seperate into two bubbles interfered {written up right side of page]] with the result.
[[upper left]] 114 April 22nd 1844 I thought to day of a process by which the force of tension inward of the bubble could be approximately obtained. [[image]] When a bubble is touched at its lower side to plate which has been moistened, it spreads out until it forms a perfect hemisphere. The reason of this ^is that the attraction of the plate for the film draws it down and would cause it to cover the whole surface were it not that through the suction of the contained air, [[strikethrough]] and [[/strikethrough]] the contrast. The force of the bubble comes in opposite to this attraction, and the two forces are evidently in equilibrium when the [[strikethrough]] perpendicular [[/strikethrough]] sides of the bubble are perpendicular to the surface of the plate, or when the bubble assumes a perfectly hemispherical form. While the bubble is spreading, if a [[strikethrough]] thin [[/strikethrough]] film of water be poured on the plate, this will be drawn before the bubble, or if a sheet of water be placed on the plate, the water within the bubble will be found lower than on the outside by at least the 1/20 of an inch. [[image]] [[in the margin]] For a paper on the strength of boilers, see Franklin Journal, vol 32, pg 54. F=force of steam P=cohesive force E=exchange d=diameter F= 2PE --- d [[end of note in margin]] [[line across page]] The result of the last arrangement was not satisfactory. I therefore made the following. A glass tube was twice bent at right angles, one part of it having first been drawn out into a tube of of about the 20 of an inch in diameter. The other part was about 5/8ths of an inch. This inverted syphon was filled with soap water, and the liquid was observed to stand higher in the smaller leg. Its position was accurately determined by means of a scale [[underlined]] d [[/underlined]] placed behind the small end of the tube, and a microscope with a glass of short focus placed before. the scale was one belonging to a set of math instruments, and the microscope one for reading off the [[circle]] vernier [[/circle]] of an astronomical quadrant. The divisions of the scale were the 1/45 parts of one [[end of page]] [[start page]] [[upper left]] April 22nd 1844 [[upper right]] 115 inch, and these divisions by means of the microscope, could readily be divided into four or more parts. The ring of wire [[underlined]] E [[/underlined]] was first dipped into soap water, and thus furnished with a film of the liquid which was then passed over the end of the tube. Next, the blow-pipe (a common clay pipe), was charged with soap-water, and a bubble blown on the wire so that the tube might be open in the interior of the bubble. When the bubble had attained the size of five or six inches, the height of the water was observed through the microscope, and this in all the experiments were observed to remain constant until the bubble became so thin at the top as no longer to sustain the contractile force of the [[strikethrough]] lower part, it therefore broke and at the instant of the rupture, the water in the smaller tube was seen to descend, and from the mean of a number of observations, I concluded that the descent was about 1/3 of one of the divisions or 1/45 X 1/3=1/135 of an inch. This depression of the water is the measure of the contractile force of the sides of the bubble. It differs considerably from the estimate I gave with the other method which was [[circle]] visiated [[/circle]] by the attraction of water for the bottom of the disc causing more water to be expelled from under the bubble than was due to the tension of the air within. I do not see any objection to the method I have here given, but in order to insure comparable results, it is necessary that the liquid in the larger leg should stand half an inch below the upper end of the tube, otherwise the form of the curve of capillarity will be altered, and the liquid in the smaller end be changed in altitude on this account. The soap bubble is capable of illustrating several of the principles of capillarity. If a piece of fine wire be bent into the form of a ring of 5 inches in diameter, [[end page]]
[[upper left corner]] 116 April 22nd 1844 [[image]] with a [[image covers text]] left project into a strong . . . film will be drawn . . . city of the liquid may be . . . the film a quantity of. . . substance, which is . . . water, a considerable . . . borne before rupture . . . If the same wire be dipped into ^ [[obscured word]] water [[word crossed out]] edge-wise, the liquid will be observed to mound along the sides ^of the film, as it would along the surface of a plate of glass plunged in the same manner into the liquid. This illustrates the fact that the support of the water in the capillary action is due to the attraction of the liquid for itself, or at least in a considerable or I should say principal degree, according to the theory of Poisson, the solid does have some effect, but I should think it imperceptible. The bubble while in a state of tension, cannot be brought readily into the sphere of attraction, this is shown by touching the lower part of a bubble to the film across the ring of wire, the two will not coalesc, but if a drop of water be pendant from the lower side of the bubble, union instantly takes place. [[image of bubble held by a wire ring]] [[image of drops poured onto surface]] Another experiment of some interest may be exhibited, showing the attraction and repulsion of the film forming the bubble. Two bubbles may be blown in a ring (one however is sufficient for the experiment), and soap water may be poured on this in a stream the 1/8 of an inch in diameter, without [[end page]] [[upper left]] April 22nd 1844 [[upper right]] 117 breaking it. If the liquid be poured on, so as to strike the side of the bubble, it will be reflected off as if repelled. If the stream strike the top of the bubble, it will pass entirely through, and although the bubble will be violently agitated, it will not break, if the operation be conducted with proper caution. In the second case, the water comes within the attraction distance and unites with the film, so that the exterior and contractile [[sufferance]] of the liquid and the surface of the bubble form one extended surface. The same experiment may be exhibited by means of the ring of wire across which a film of soap suds is stretched. For this purpose the water may be poured from a cup with a lip in a continued stream, and if the operation be carefully performed, the film will not be broken although much agitated. [[image]] A pretty exhibition is produced by attaching a bladder to a ring, and then thrusting a pipe into the upper end of it, which may be readily effected if the pipe be wetted, and then blowing a second bubble. The two will swell together, and show a brilliant set of iridescent colours. Why does the bubble spread, when it touches the surface? Because the attraction of the sides of the [[strikeout]] water [[/strikeout]] bubble draws up the water by capillary attraction, and more is accumulated on the outside than on the inside, and hence the sides are constantly drawn out until they become perpendicular to the flat surface of the plate or the water. See figure in margin. [[image-bubble]] [[image-bubble]]
(116) April 22nd 1844 [[image]] with a piece of the same wire left projecting, and this be dipped into a strong solution of soap, a film will be drawn up and the great tenacity of the liquid may be shown by throwing on the film a quantity of cotton, or some light substance, which is not readily wet with water- a considerable weight will be borne before rupture. [[image]] If the same wire be dipped into ^[[the soap]] water [[strikethrough]] then [[/strikethrough]] edge-wise, the liquid will be observed to mound along the sides ^of the film^ as it would along the surface of a plate of glass plunged in the same manner into the liquid. This illustrates the fact that the support of the water in the capillary action is due to the attraction of the liquid for itself, or at least in a considerable or I should say principal degree; according to the theory of Poisson, the solid does have some effect, but I should think its imperceptible. The bubble while in a state of tension cannot be brought readily into the sphere of attraction, this is shown by touching the lower part of a bubble to the film across the ring of wire, the two will not coalesc, but if a drop of water be pendant from the lower side of the bubble, union instantly takes place. [[image]] Another experiment of some interest may be exhibited, showing the attraction and repulsion of the film forming the bubble. Two bubbles may be blown in a ring (one however is sufficient for the experiment), and soap water may be poured on this in a stream the 1/8 of an inch in diameter; without [[end page]] [[start page]] April 22nd 1844 (117) breaking it. If the liquid be poured on so as to strike the side of the bubble, it will be reflected off as if repelled. If the stream strike the top of the bubble, it will pass entirely through, and although the bubble will be violently agitated, it will not break, if the operation be conducted with proper caution. In the second case, the water comes within the attraction distance and unites with the film, so that the exterior and contractile [[sufferance?]] of the liquid and the surface of the bubble form one extended surface. The same experiment may be exhibited by means of the ring of wire across which a film of soap suds is stretched. For this purpose the water may be poured from a cup with a lip in a continued stream, and if the operation be carefully performed, the film will not be broken although much agitated. [[image]]A pretty exhibition is produced by attaching a bladder to a ring, and then thrusting a pipe into the upper end of it, which may be readily effected if the pipe be wetted, and then blowing a second bubble. The two will swell together, and show a brilliant set of iridescent colours. Why does the bubble spread when it touches the surface? Because the attraction of the sides of the [[strikethrough]] water [[/strikethrough]] bubble draws up the water by capillary attraction, and more is accumulated on the outside than on the inside, and because the sides are constantly drawn out until they become perpendicular to the flat surface of the plate on the water. See figure in margin. [[image]] [[end page]]
[[image – drawing to the left of handwritten notes, depicting plates and hourglass shaped figure with rings labelled "a"]] 118 If two plates or films of soap water be dipped into the soap water, the liquid we might suppose would be elevated between them, as if it were between two plates of glass, but this I find not to be the case, the two films are drawn together by the attraction of the water.* When a large bubble attached to the ring [[underline ]] a [[/underline]] touched at its lower point to the surface of a moistened plate, the bubble adheres and spreads out as in the figure. If now it be drawn upward by the ring, it will be observed to contract at about [[underline]] b [[/underline]], and grow smaller and smaller at this point as the ring is lifted upwards, and finally it separates into two parts, leaving a hemisphere on the plate and a smaller spherical bubble on the plate. To explain this action, we may imagine the bubble made up of a series of rings which tend to contract by the contractile force of the surface into a smaller dimention. The difference between a bubble of pure water and one of soap water, may be illustrated by the comparison of an arch in the one case formed of parts or wedges without friction, and in the other of parts which have lateral adhesion similar to friction. In the first case, the arch will have the same inward pressure, but will be instable and in the second stable. [[image – drawing of a hand pointing to left of handwritten notes]] Make bubbles of gum water. A bubble may be prolonged in existance by blowing under it in the air, so as to cause it to roll over, making the lower part the upper. T Dean Bubble of gum water, also film of the same [[word circled]] dried [[word circled]] T. Dean *This experiment has a bearing on the question of the circulation. [[end page]] [[start page]] July 5 1844 119 Prepared this morning the apparatus to attempt to get the interferance of [[circled]] cold [[circled]], but before I was fully prepared to operate, the sun failed me and I was obliged to give up the experiment for today. I next drew a copper wire from Mr. Clow's well to the electrical machine across the room. When sparkes were thrown on the ball on the end of this wire, sparks could be drawn from all along it towards the well, inconformity with what I have before published. The wire was afterwards opened, and one of the intensity wire inductric spirals placed in the space. A pain of glass was placed over this, and a second spiral on this again. The result was the same as that which I had previously observed, but with the additional fact that the electricity tends to fly off from the secondary wire in the same manner, as from the primary wire. This is a new fact, and appears to have a bearing on the facts of the lateral discharge. The experiment was varied by disconnecting the long wire leading to the well, and sending the charge directly through the spiral from a Leyden jar. The result was the same, the sparks were given off. [[drawing - wires connected to a flat surface with an item in between them]] In the afternoon of this day I repeated an experiment described to me in a letter from Dr. OSchaunessey of Calcutta, which is as follows: A discharge of electricity from a battery of 6 jars is passed through a slip of tin foil of about an inch wide, and 6 inches long, when the foil is dry, the discharge passes silently, but when the foil is wet, a bright flash is seen along the surface - when percussion powder (silver salt) is sprinkled along the surface, an explosion takes place when the foil is wet, but not when dry. [[end page]]
[[page]]120[[/page]] July 5th 1844 This experiment was repeated by using two jars, and the apparatus from France for a spark in water. See figure on opposite page. When the foil was wet, and but partially submerged, the light on the foil was very distinct, but when the water was gradually increased, the effect was less and less, and when the water in the basin of india rubber stood at the depth of half an inch over the foil, no light was observed. The same experiment was tried with 8 jars, the small [[?]] battery, but the effect did not appear greater than with two jars, and indeed it appeared less. The intensity was less, and the effect appeared to depend in some degree on the intensity. I think it probable that the effect is due to the distribution of the electricity towards the surface, and the bad conduction of the water. For a notice of a paper on the spreading of oil on water, see bundle of scraps in my drawer under book case. See note in the Proceedings of Polytec Inst. on the relative attraction of different liquids. The compressibility of ice appears to be very little different from that of water, the true distinction between liquids and solids in the lateral adhesion which probably depends on the lateral adhesive. Quarterly Rev 1812 p32. [[end page]] [[start page]] Sept 28th Saturday 121 [[image - sketch of hemispherical bubble]] In a conversation with Mr Dean of Vermont yesterday, he suggested the idea that the bubble of soap water was not perfectly hemispherical, to determine this I measured several bubbles this morning in altitude and radius, and found the two to be equal. The measurement was not made with great care, but the difference from a semicircle could not be much. (Make the measurement again by cutting out a piece of card in the form of a semicircle. ) [[image - sketch of a bubble near the edge of a plate]] I observed today that when a bubble was thrown on a plate and pushed to the one side, it moved until it came on the edge, altering its shape from that of a hemisphere. This effect I reffered after some study, to the action of the capillarity, the sides of the bubble are always perpendicular to the surface of the solid with which it is in contact. [[image - a sketch of the apparatus described]] From the consideration of the theory of the soap bubble, I concluded that the contractile force of a small bubble is greater than that of a large one, and to test this by experiment, I made the above arrangement of a bent glass tube with a large phial (3 inches across) on one end, and a small phial of one inch in diameter on the other, the bottoms of the phials being removed. The open end of the large glass being dipped into the soap water, and then the breath blown into the other phial, a large bubble was inflated on the large end, after this with a tobacco pipe, a small bubble was blown on the smaller end, the contractile force of the smaller one was shown to be greater than that of the larger by the diminution of the former, and the increase [[end page]]
[[page]]122[[/page]] of the latter. The smaller bubble did not stop collapsing, even when its curvature was the same as that of the large bubble, and this was might have been anticipated, since the diameter of the glass on which the bubbles rest were different, and the greater curvature of the smaller phial would increase the effect of the contractile force. [[image - simple sketch of the arrangement described]] For exhibiting some of these experiments, a common watch glass may be used, a small bubble being blown on the smaller end, and a larger one on the other, the latter will increase, and the other diminish until it becomes nearly a plane across the end of the tube. [[image - simple sketch of the arrangement described]] If a bubble be blown on the end of the glass chimney, the part of it which comes in contact with the inner part of tube, will be seperated and forced down the tube in the form of a circular disc, and if the chimney be lifted up from the plate on which it rests, the bubble will instantly collapse while the diaphragm will be driven down. [[image - simple sketch of the arrangement described]] When two bubbles touch each other, they exhibit at first a repulsive power, and do not unite unless the percussion be of some ^[[little]] intensity, they then unite, and the circle of contact widens until the surfaces are nearly if not quite in the same cylindrical surface, the space of contact is a perfect circle, and if the two bubbles are of the same diameter, this will be a perfect plane, the contractile force being the same on each side, but if the one be smaller, the plane will be convex from this.[[end page]] [[start page]][[page]]123[[/page]] The rushing together of the two bubles may be explained [[image]] [[a>---
[[Start page]] 124 Mr Esky this evening has directed my attention to the experiment of Savart on jets falling on a plate. The water is thrown out, and forms a parabola at one velocity and almost a sphere at another. Mr. E thinks that these have a bearing on the tensity of water. [[image-drawing of circle with two lines exiting top]] I have observed as stated on the last page, that when the soap bubble bursts, it appears to resolve itself into minute bubbles, and this fact appears to me to be connected with the vessicular condition of water in the form of fog [see Raimitze [[?]] Meteorology page 110]. Would not the vapors be condensed on the surface of a spherical portion of vapor? and would this not give rise to the insufficient formation of the vessicle? If this be the process, we would at first have a bubble of water enclosing vapors and air; the vapors would be absorbed by the sides of the bubble, since the forces [[stricken]] is [[stricken]] ^[[are]] greater then inversely as the square of the distance. What ever be the method by which these little bubbles may be formed, it is certain that there is a tendancy in water to resolve itself into these forms. If the insipient drop is not perfectly spherical, or I should say convex on all sides, the circular contractile force would tend to [[underline]] nip [[/underline]] it into a [[strikeout]] sphere [[strikeout]] hollow sphere. [[end page]] [[start page]] December 18th 1844 [[squiggly vertical line]] Breaking of wax and metal [Commencement of the vacation under new college arrangement] 125 Made a few exp today on the breaking of sealing wax - found that the wax when partially softened so that it could be drawn out, broke so as to leave on the end of each piece a cup shaped orifice, of [[image - horizontal tube]] which this figure will serve to give an idea. Also when the wax was stretched and elongated permanently, the stretching appeared to be greater on the outside, for when the cylinder of wax was supposed to contract, the surface exhibited a surface traversed crosswise with a great number of creases or folds, as if the [[strikeout]] outer [[strikeout]] surface had become too large for the inner part. The explanation of the fracture exhibited by the wax is the same as the above. The surface was unduly stretched, and hence when the rupture took place, the outside was too long for the inside. Or in other words, the outside of the wax had been stretched so as to take a set, and therefore could not recoil as much as the inside. Next a piece of thin leaden wire was broken by pulling, when the same [[circled]] effect [[/circled]] as to the cup-shaped fracture at the end was exhibited as in the case of the wax. Also a piece of copper wire was broken in the same way, and with the same result, except that the cup was not as deep as in the case of the lead. I found that when the lead was held in the flame [[image in margin - hand pointing]] of a spirit lamp, the metal was brittle, and the fracture a granulated plane surface. Lead before it becomes liquid, assumes a granular texture like sand.
126 Dec 24th 1844 Experiments made in Phid on tenacity of water. My Frend, Mr. Eckfelt of the United States Mint, kindly offered to assist me in making some experiments on the tenacity of water. Two discs of copper were prepared under the superintendance of Mr. E. These were circular and flat; the one two inches in diameter, and the other one inch. They were experimented with in succession by being suspended and [[word crossed out]] cone [[/word crossed out]] horizontally from one end of one of the delicate balances of the mint, and counter poised by a weight in the opposite scale. The water employed was distilled, and the room was kept [[word crossed out]] of [[/word crossed out]] at the temperature of 65°. The following were the results: grams Pure distilled water, one inch disc 41.52 " " two inch " 165.30 These are deduced from the means of a number of experiments. Saturated solution of Neusor soap with the one inch disc grams 25.46 Capillary Weight measure The specific gravity of the water saturated with soap, was not increased more than 1/1000 or one 1/10 of a percent. [[image]] Cotton placed on a ring 3 inches in diameter, broke with a weight 8 grams. In another exp. the weight of cotton was 11 gms. Each disc was elevated as follows: The one inch about 3 divisions of a scale .065 of an inch. The two inch about 1 1/2 of the same. The water which adhered to the disc after separation in each case was 3/4th of a grain. [[end page]] [[start page]]127 Dec 24 1844 | Tenacity of water [image] When a soap film was placed across the mouth of a glass funnel, it was not at any point in a state of equilibrium, but moved up towards the apex of the curve. The cause of this is easily understood, the attraction on account of the greater inclination of the film on one side, rather than on the other, caused the motion. [[line across page]] Called the same morning at the Cornelius', the lamp manufacturers, was shown the experiment which he had instituted at my request some months before, namely, the sinking [[word crossed out]] of silver into copper. I had asked him on a former visit whether he ever found the silver from plated copper to disappear in heating it. The answer was "yes, it evaporates." does it not, said I, sink into the copper. He made the experiment and found the result which I had anticipated. To remove the copper, he first used a galvanic battery, the copper being placed on the pole which would cause solution, but afterwards, he found that the silvered surface could be restored by dipping the plate into the soldering liquid, mureate of zinc. He showed me a piece of plated copper uniformly covered with silver, which he heated at one end over the forge until the silver disappeared, and the surface exhibited the appearance of copper, this was then dipped into the zinc liquid and the silver again appeared. Mr. C. informed me that the [[word crossed out]] knowledge of this process would a few years ago have saved him many hundred dollars in the course of a year. Articles of plated metal [[word crossed out]] were often spoiled by the disappearance of the silver as he supposed by evaporization. The fact is not now of as much consequence, since the plating process is carried on in his establishment by means of the galvenic process. [[end of page]]
[[circled]] 128 [[circled]] Dec 24th 1844 | Exp. on molecular action Mr Eckfelt of the mint has made a series of experiments on the specific gravity of metals, as changed by hammering and heating. Mr Magand of Philadelphia thinks that no pure metal can be hammer hardened. I have seen it stated somewheres that heat is given out in the striking of discs during the first stroke, but not the second. Ask if the specific gravity is increased by the process of coining. Mr. Cornelius showed me the operation of a new polishing powder he had discovered, it is nothing more than Henrys calcined magnesia. It gives a remarkable fine polish to steel. It is applied by rubbing on a surface of canton flannel. It possesses one advantage insofar to the galvanic process of guilding, it can be removed from the surface by a strong solution of sugar which, according to the statement of Mr. C., disolves the magnesia, and in this way removes it from the surface, other substances adhere and cannot be entirely removed. Mr. C proposes to make a reflector for a telescope by means of the galvanic process and then cover it with a coating of silver polished by this means. (For an exp on Molecular action, see p. 69) [Dr. Ellet informed me that when the water was passing off the front side of a Daguerreotype plate, which had been set on edge to drain, small nodes was seen moving up the inner surface of water.] For Savart's paper on the sheet formed by water impinging on a disc, see Annales de Chemie 54, p 123 - 1838. He finds that at the maximum density of water, the diameter of the conical sheet is the [[strikeout]] greatest point [[/strikeout]] [Make experiments on the adhesion of plates at the point of maximum density]. Repeat the exp of savart with soap water. *The viscosity of the water is the [[strikeout]] least [[/strikeout]] greatest at the maximum density. [[end page]] [[start page]] Jany 3rd 1845 } Hole in card Holes in pierced card [[circled]] 129 [[circled]] Purchased five large clock shades from Mr. Pike in New York, which had been covered with tin foil for the purpose of forming a large electrical battery. After considerable trouble in getting them to Princeton and in fitting them into a box, I was much disappointed to day in finding that I could not give them a charge, or at most but a very feeble one. The glass is quite thick, but I do not think this is the difficulty. Repeated to day an experiment previously made in reference to the number of holes in a pierced piece of paper, found as before that when the paper was placed obliquely between the points thus [image] it was pierced with several small holes and one larger, but when the paper was placed directly at right angles to the line joining the points, but one large hole was made. [[in margin]] see page 81 [[/end margin note]] To determine if the same effect would take place in a vacuum, the shock was sent through the paper which had previously been placed under the receiver of an air pump. The number of holes was now greater than when the discharge had been made in the open air. From this experiment, it appears that the air causes the discharge to scatter less. This must be repeated. Also made an experiment on the phosphoresence of the salt called sulphate of potassa placed in a vacuum between two needle points. The salt glowed [[strikeout]] big [[/strikeout]] in this case as if it had been subjected to a weaker shock in the open air.
[[circled] 130 [[ circled]] Jany 4th 1845 | [[underlined]] Heat of Spots on the Sun [[underlined]] Saturday In one of the late Nos of the Annales de Chimie et Physique, there is a paper on the subject of the diminution of heat during the appearance of solar spots. In looking over this article, I was struck with the ease [[insert]]with[[insert]] which the question of the heat from these spots could be determined by the use of the thermo-electrical apparatus. Sir W Herschell thought that the spots were hotter than the bright part of the sun, while the investigations of the author of the paper in the Annales would seem to show that the spots were cooler from the fact that in the years where the greatest number of them appeared, the mean temperature of different parts of the Earth was [[insert]]slightly[[insert]] less. He determined this by grouping the periods in which the spots were the most numerous, but little reliance can be placed on observations of this kind, for although the spots may be [[measurably?]] colder, yet the difference is probably so small, that it cannot be determined with any degree of certainty, as will be evident in comparing the area of the spots with that of the whole disc of the sun. Yesterday morning, Mr Alexander announced to me the appearance of a very large spot on the sun of which he had taken the measurement, and found it to exceed the Earth in magnitude. He then agreed to make an experiment in reference to the heat of this spot. We did not however get fully prepared before the disappearance of the sun under a very extensive surface of cloud. This morning however, the sky was remarkably clear for this season of the year, and we accordingly proceeded to make the attempt. For this purpose, the Fraunhoffer telescope, belonging to the college, was brought [[END OF PAGE ]] [[START OF PAGE ]] [[circled]] 131 [[circled]] Jany 4th 1845 | [[underlined]]Spots on the Sun [[underlined]] from Mr Alexanders house, and placed in my little room at the Hall, the window being darkened by green baize, the end of the telescope being suffered to project out of the window. A very distinct and beautiful image of the spot was thrown on [[strikeout]] the [[/strikeout]] a screen of about 2 inches in diameter, [[?]] the umbra. The black part of the spot was about 3/4 of an inch in diameter, a little larger in one direction than in the other. Its form was something like this: see margin, p 139. [[image of experimental set-up with telescope and window]] The arrangement of the apparatus is represented in the above sketch. a the telescope, w the window, p the thermopile, s a paper screen with a hole in it of the size of the pile - the screen was fastened to the end of the pile by a little soft beeswax, g-the galvanometer supported on a shelf let into to the wall at one end, so as to be steady and not movable with the [[?]] of the floor. On the top of the [[insert]]glass[[/insert]] cylinder which contains the apparatus, was placed two magnets furnished by the maker of the instrument, which could be opened or shut at pleasure, and these were intended to change the zero point of the apparatus, and render the whole more [[?]].
132 The difference in the results between the two observations would have been greater probably had the temperature of the room been less. This was about 65, and the sun's rays increased the heat beyond this, but a few degrees of the scale of Melloni. sun dif in quarters dif in quarters Spot 3 1/4 Sun 5 1/4 Sun 4 1/2 5 Spot 4 5 Sun 3 Spot 4 1/2 Spot 1 3/4 5 Sun 5 2 Spot 2 Sun 4 1/2 Sun 3 4 Spot 3 3/4 3 Sun 2 1/2 Sun 2 Spot 2 2 Spot 3 1/4 5 Spot 2 Spot 0 3/4 Sun 2 1/4 1 Sun 2 1/2 7 Sport 4 3/4 Sun 1 1/4 Sun 5 5 Spot 0 - 5 This spot would have been a very beautiful object for the photographic process. The whole difference on an average is 1 1/12 of a degree of the apparatus. On the evening of the same day, made an experiment with John Stockton on a diamond ring containing three stones. The ring belonged to Stockton or was in his possession. The exp consisted in passing a shock from a single jar over the ring at the distance of an inch and a half. The diamonds glowed with a whitish phosphorescent light, which was not as intense as that from the sulphate of potassa with which it was compared. This affords a simple method of detecting the diamond. [[end page]] [[start page]] Jany 8th 1845 133 Show [[Hunres?]] Exp on Lateral discharge etc [[Image]] Prepared two discs of wood with tin foil on the inner surfaces each 32 inches in diameter. Suspended one of these from the prime conductor, or rather connected it with the same. Then threw sparks on the middle rod (a) while the rod (b) passing through the glass tube was held at the distance of about 1/8ths of an inch. Sparkes passed redy between [[underline]] a [[/underline]] and [[underline]] b [[/underline]], but none between [[underline] c [[/underline]] and [[underlined]] a [[end underlined]], except a very few small ones. The boards or discs were at the distance of 8 1/2 inches apart. The Buckle being placed on the upper surface of the wider disc, sparks were received in abundance With this arrangement, sparks 3/4 of an inch long passed between [[underline]] a b [[/underline]]. But with the short conductor [[underline]] c [[/underline]], as in the figure, no sparkes passed. When short wire was placed at [[underline]] d [[/underline]], a spark was seen at each discharge at the two ends [[underlined]] a f [[end underline]]. When [[underline]] e [[/underline]] touched the wire, no spark was seen at f. Also when the ball [[underline]] f [[/underline]] touched, no spark was seen at e. The wire d in these experiments was about 16 inches long with a ball at each end, as shown in the drawings, and the wire was out of the influence of the induction of the large plate. So that the effect does not depend on the presence of the large conductor underneath.
[[start page]] 134 Jany 8th 1845. The result obtained on the last page appears not difficult to explain; the wire in its whole length tends to give off electricity, and consequently the spark tends to pass at each end, and consequently when the balls are at a a little distance from the conductor, [[image]] a spark is seen at each, but here one ball is in contact, [[image]] thus no spark passes at the other because the small wire is now a part of the large one, and each tends to give a spark to the other. [[image]] [[line across page]] Next placed the middle wire or long conductor a in a, glass tube; in this case, sparks 1/2 an inch long passed between G and the end of a, both when it was connected with the under plate and when it was insulated by a glass tube. sparks about the same with and without the insulation of the second conductor. When the finger was applied to the upper surface of the lower plate, sparks were obtained, but they were not as strong as in the case of the no insulation of the middle conductor a. Tried the two in immediate connection. [[image]] Placed on the edge of the lower plate the set of magnetizing spirals, found the current upwards. The needle conductor a being connected with the ground but insulated by means of glass tube at d. The wire connected with the spirals was connected at the farther end to the stove. [[end page]] [[start page]] Jany 8th 1845 135 Repeated the last experiment with the tube withdrawn, or the conductor touching the under plate. The effect was not the same as before, [[? strikethrough]] current was [[underlined]] downwards [[/underlined]]. In each of the preceeding experiments, the needles in all the [[underlined]] four spirals [[/underlined]] were magnetized in the same direction. Repeated the two last experiments. When the tube was in place, or the middle conductor insulated, a current was produced in the spirals [[underlined]] upwards [[/underlined]] When the tube was [[strikethrough]] connected [[/strikethrough]] withdrawn, and the middle conductor made to touch the tin foil of the lower disc, the current was [[underlined]] downwards [[/underlined]] These results were in accordance with my anticipation. When the spark passed down through the under plate without connectivity with it, the restoration of the natural electricity which had been drawn down by induction, caused the upward current, but when the the middle conductor was connected with the lower plate, the restoration was effected by means of the discharge from the machine, and on the principle of the divergency in all directions, the spark is sent downwards, in this case counteracting the tendency upwards. [[image]] The two plates were then separated to the distance of 4 feet 2 inches. The current was still perceptible at this distance. [[image]] Next placed between the two plates a window shutter [[image]] about 3 feet by 4. The needle connected with the lower plate was magnetizing.
136 Jany 8th 1845 [[Three drawings in the left margin top of page]] Next made arrangements to get signs of this induction in, for this purpose suspended the upper plate at the distance of about 18 inches from the floor, [[strikethrough]] with this arrangement [[/strikethrough]] and the under one was at first placed with a foot of the ceiling beneath by means of a long pole on the top of which it was supported. The end of the wire [[underlined]] a [[/underlined]] was attached to a lead pipe connected with the line gutter of the house. When the sparks were passed between a ball and the machine, the needle became magnetic in one of the spirals,- and so strong was the induction, that sparks were heard passing between the spires of the helix.- The whole of this effect consisted in suddenly relieving the upper plate of the redundant electricity, and at that just the natural electricity returned to the plate below. (This experiment was completed on the morning of the 9th,-preparations on the 8th.) [[squiggly line across the page]] Made a few experiments in the evening on the illumination of a long thin wire [see my communication to the British Association 1837] Found nothing new of any consequence. Found that there was no perceptible difference in the affect as judged of by the eye, whether the sparks thrown on the end of the long wire were from the long 14 feet conductor, the large plate,- or the ball of the machine. I also tried the effect of [[image]] placing wire points on the wire as at [[underlined]] a [[/underlined]], but the brush was not longer from this than from the other part of the machine. [[end of page]] [[Start of page]] 137 Jany 9th 1845 [[drawing in left margin of page]] The last experiment was extended by elevating the upper plate to the distance of 5 feet above the floor, and gradually depressing the lower plate until in the last attempt it rested on the floor of the room below. With this distance, the effect was still perceptible. The needles were magnetized with an ascending current, that is with one upwards towards the lower plate. This effect was produced as in the last case, by discharging the upper plate. The whole distance at which this induction was manefest in this experiment, 5+1+13= 19 feet through a floor of about one foot thick, consisting on the upper side of inch boards, and on the under of lath and plaster. [[squiggly line across the page]] Next attempted to to produce the induction in the room next below the last, namely in the kitchen, but in this I was not successful, no signs of the effect could be perceived. The experiment however was not very well conditioned, I could not get a good discharging train, and the plate was not insulated. From the result of these experiments, I do not doubt that inductive effects from the clouds could be obtained by mearly insulating a disc of the kind I have used; and connecting this with the ground by means of a fine wire in the circuit of which a spiral is placed. [[end of page]]
[[checkmark]] 138 Jany 9th 1845 [[vertical wavy line]] I think it probable that the results of the last page might be obtained at almost any distance by making the size of the lower plate commensurate with the distance of the discs apart. This is on the supposition [[triangular image]] that the force decreases as the square of the distance. The under disc should increase as the square of the distance, or its diameter should vary as the distance. But this again is on the supposition that the upper excited body is a ball. [[line drawn across the page]] [[image of jar + wire]] [[Note on image: See page 149 also p 167]] Arranged a jar as in the figure, sent shock through, spark appeared at b. Next made the loop [[underline]]b[[/underline]] C much larger, spark appeared brighter. Again seperated the wires at [[underline]]b[[/underline]], and interposed the body, but no effect could be observed. This experiment would appear to indicate that the consecutive parts of the discharge were in different states at the same moment. [[end page]] [[start page]] Jany 10th 1845 [[vertical wavy line]] spot on the sun [[< <]] 139 Made this morning another observation with Mr Alexander on the spot of the sun. Since the time of the last observation, the weather has been cloudy. The sky was not perfectly clear to day, and during the time of the observation the sun was partially obscured by a thin veil of clouds, the observation was therefore not as satisfactory as the one made before. The arrangement however was somewhat improved, the farther end of the pile with the reflector on was wrapped in cotton of the temperature of the room, which in this case was 48˚. A low temperature of the room was purposely chosen with the expectation that this would make considerably greater difference in the suns rays above [[strikethrough]] about [[/strikethrough]] the heat of the room, but this difference did not appear any greater than that of the previous observation, and after some reflection I am not sure that the heat of the [[circle]] circum. [[/circle]] ambient space produces any effect, and that the result is not entirely due to the difference of temperature of the two ends, and that we might determine the difference of temperature between two pieces of ice. What ever may be the truth [[circled word/phrase]]inregard[[/circled word/phrase]] to this circumstance, the results of the observation of today was the same in kind as that of the last observation, the spot indicated a less degree of heat. It had changed its appearance very much since the last observation, was much less in size, [[strikethrough]] and passed over [[/strikethrough]] also the sky was less clear, and the veil of cloud constantly thickened. appears on the 4th [[egg-like image]] appearance 1st day of observation appears on the 10th [[dividing egg-like image]] app- 2nd day of obs 1 Sun 4˚ Spot 3 1/2 [[right margin]] 1/2 [[vertical line]] 2 Sun 3 1/4 [[right margin]] cloud [[vertical line]] 3 Sun 3 1/2 [[right margin]] 1/4 Spot 3 1/4 [[vertical line]] 4 Sun 3 1/4 Spot 3 1/8 [[right margin]] 1/8 [[vertical line]] 5 Sun 3 3/4 Spot do. [[right margin]] cloud
140 Jany 10th 1845 [[vertical line-wavy]] Mercury through lead rod. Placed this morning the lower end of a lead wire of about the 1/20th of an inch thick in a cup of mercury, with the intention of noting how high and how rapidly the mercury will be drawn up. The arrangement was made at one colock. [[image labeled 1 in margin]] In a previous experiment made [[strikethrough]] at [[/strikethrough]] or rather arranged last session, I found to day in measuring the wire and weighing the mercury, that it draws if the metal passed through 3 1/4 inches of lead tube in about 4 mints. The wire was 1/7th of an inch in diameter. The difference of the legs of the syphon was 2 inches. The downward force therefore was equal, the attraction of the earth on the mercury. This time indicates a very slow motion, although the appearance of the mercury at the lower end of the tube is much quicker than the velocity indicated by this experiment would show. [[image labeled 2 in margin]] A drop is always formed at the end of the tube, and this gradually accumulates until the weight causes it to break off, but the contractile power of this drop must tend to retard the flow of the mercury, and I think there is little doubt that more of the metal would pass over in a given time, if the lower end were dipped into mercury. [[underlined]] Jany 11th [[/underlined]] Examined this morning at 1/2 past nine oclock the leaden syphon which I arranged yesterday at about one o'clock, and found that the mercury had already passed and was hanging in the form of a partial drop at the lower end- It had passed through the whole [[strikethrough ]] [[?]] [[/strikethrough]] of the metal which was evidint on breaking the wire, and examining the fraction by means of a microscope. [[image in margin] [[end page]] [[new page]] Jany 11th 1845 [[vertical line wavy]] Mercury through lead rod 121 The wire in this experiment was about 5 inches long and 1/20 of an inch thick. By the side of this syphon, another had been placed which had been used in a previous experiment for transmitting mercury. But although this was not more than half the length of the other, no signs of mercury were visible at the lower end. Perhaps the mercury and the lead in time forms a stable compound. Also examined the arrangement (1) on last page, found the mercury had ascended one inch and 6/10. The line of demarkation around the wire which seperated the mercury from the pure lead, was very distinctly marked. When the wire which had been used for transmitting the mercury, was rubbed by the finger, it exhibited a bright polished mercurial surface, and when the same wire was bent, the polish disappeared both on the convex and concave side, and was succeeded by a granular or roughened surface. Examined the long perpendicular wire on Monday 13th at 1/2 past nine. All, found the mercury had [[reassessed?]] to the height of 2 inches, & 7/10. Tuesday 1/4 after nine AM, mercury 4/10 of an inch higher than yesterday-highest on side next the light. Wednesday 15th 1/2 past 9- whole height of mercury 3.6 inches Thursday 16th 10 oclock- whole height 3.9 inches Friday 17th 1/2 9 oclock whole height 4.2 Saturday 18 10 oclock whole height 4.7 Monday 20 10 oclock 4.5 (In adjusting the wire on Saturday, about an inch of the lower end was broken off. This interferes with the series of observations.)
142 Jany 11th 1845 [[vertical line wavy]] Observation on the sun's limb Made another observation on the sun in order to determine whether the middle or limb were the hotter. The spot noted yesterday had materially altered its appearance. It now appeared as in the [[image]] sketch, and was so small that we did not attempt to determine its difference of temperature, but proceeded to observe the difference between the two limbs. For this purpose, a lens was applied to the telescope which magnified 74 times the image of the sun, at the distance of the thermo pile was about 32 inches, where as in the experiment of yesterday, and that of the other day, the image was 80 inches. [[?]] this smaller image, the effect on the pile was much more marked, the needle took a position with the middle of the disc moved to near thirty degrees. The following are the observations: 1st Sun's centre 27 do Limb 25 Sun's centre 26 3/4 2nd Sun's Limb 24 centre 26 3/4 [[note-- in brackets to right of 1st and 2nd]] Sun clear 3rd Sun's centre 26 " Limb 24 [[note-- in brackets to the right of 3rd]] paper on the All there were on the [[underlined]] west [[/underlined]] limb of the sun [the east the screen] [[end page]] [[start page]] Jany 11th 1845 [[vertical line wavy]] Sun's limb 143 Sun's limb 22 1/2 " centre 23 1/4 Sun's centre 27 3/4 Limb 25 1/2 [[note to right of sun's measurements]] Slight cloud over the sun. These observations not as valuable as the others These were made on both lims in succession, the first on the East, the 2nd on the West, but these observations as to the different limbs must be repeated. The surface of the sun exhibited a mottled and wavering appearance on the screen. [[two horizontal wavy lines overlapping each other]] Attempted to get induction at right angles to a secondary, the needles were always magnetized with an upward current. [[wavy line]] [[image-- battery with spiral wires on end, then battery deconstructed below, bottle to the left]] Arranged the apparatus to get secondary current, and to pass this through a plane spiral over which a board with tin foil on it was placed as [[underline]] a [[/underline]]. When the shock was passed through the first conductor, a spark was given off to the finger, this was generally +, but on some occasions it was negative, and on others it exhibited no signes of electricity.
144 Jany(Monday 13th 1845 The sky is overcast this morning no opportunity of going on with the observations on the sun [[line drawn across page]] [[image - experimental apparatus]] Insulated jar removed cover and knob, - 2u as to charge it by means of sparks, - while the inner coating was not opposed by the outer, by this arrangement I found as I had expected,that the jar could be charged without exhibiting signs of free electricity on one side more than on the other. In this case, when the discharge was passed, no lateral spark was given off, and the wire placed as in the figure, and in connection with the earth transmitted no discharge as indicated by the needle in the spiral. This is in opposition to many of my previous accounts-, only apparently,so the plus and minus currents from different ends of the wire neutralize each other. When the same jar was charged in the usual way with a ball projecting from the middle, a spark passed to the knuckle, and the needle was magnetized by a current downwards. Next, arranged the spirals to get current of third order, found this was produced wether the jar, was used with or without a knob. The current induction therefore appears to be independant of the free electricity, although the induction at right angles appears to be dependent on it. The third current was [[underline]][[image - positive sign]] in all the [[/underline]] spirals of the set used. [[end page]] [[start page]] 145 Jany Monday 13th 1845 [[image]] Made an arrangement for Scd_ current in a detached spiral [[underline]] a [[/underline]] [see figure], and on this placed a flat board covered with tin foil. When the jar was used without knob, no spark could be obtained from the flat board, but when the free electricity was increased by using the knob and the prime conductor of the machine, a smart spark passed to the knuckle brought near the board. The arrangement of apparatus remaining as before, sparks were thrown from the machine without the jar. Now the spark from the plate was quite powerful. The discharge from the conductor is [[circle]] unaltered [[/circle]] with the negative current. Next put on the glass of the 2nd current, the spiral for a third current,_ the induction being produced by the sparks current in all the spirals was [[image - negative sign]]. In another experiment, the repitition of the last found an oscillation,_ the most convoluted spiral gave feeble - minus, the simple spiral strong minus. With the jar removed, and the spark thrown on to [[strikethrough]] [[?]] [[/strikethrough]] a ball at the end of the primary spiral, the needles were differently magnetized in the different spirals.- Commenced to examine the jar without knob etc. [[image - experimental apparatus]] First jar without knob tested by means of a [[strikethrough]] silk [[/strikethrough]] ball suspended by a silk thread[[strikethrough]]d[[/strikethrough]], found no free elect on either side.- Discharged the jar - no induction from the outside.-
146 Jany 13th 1845 Charged the jar with the knob in, now found induction. [[image - experimental apparatus. Jar sitting on a base. Base labeled as 'bees wax']] Next charged jar without knob, placed glass tube around the discharger, and end of long wire with magnetizing spirals around the outside of the tube, made the discharge, needles unaffected. Again made the same arrangement with the exception of putting on the cover, and knob discharged again, the same charge now [[image - negative sign]] the needles were magnetized by an outward current. These results thus far favour the supposition that the effects produced in my former experiments on this point, see page 61 Oc, were due to the free electricity. [[image - experimental apparatus with parts labeled 'a' and 'bees wax']] Thinking in the last experiment that the want of induction at right angles is due to the want of matter [[strikethrough]]matter[[/strikethrough]] in the end of the wire, to exhibit the same, I made the arrangement shown in the figure, in which a small conductor was placed in contact with outer surface, and in this case, the needle in the ab spiral was magnetized as if by a current outward. When the inductive receiving wire was placed as in the lower figure, then the current was slightly reversed, both exp showed a tendency to a change of polarity in the different spirals. [[image - experimental apparatus]] This is again a result in accordance with my previous experiments - [[end page]] [[start page]] Jany 13th 1845 147 [[image - experimental apparatus]] With this arrangement of two conductors inorder to make the quantity of conducting matter greater, the needles were scarcely at all magnetized. [[image - experimental apparatus]] Again tested the jar without knob and with knob. The first showed no signs of free electricity on the inside or the outside. The second when the [[curre?]] ball touched the knob, gave signes of free electricity in abundance. The jar therefore charged in this way is completely disguised on both sides. [[image - experimental apparatus]] Arranged a frame of 4 posts and passed around this a wire 22 feet long. When the knuckle or a ball was placed at ^[[a,]] no spark was perceived, but when the [[strikethrough]] [[illegible]] [[/strikethrough]] knuckle was placed [[underline]] c [[/underline]] or [[underline]] b [[/underline]], a smart spark passed. - no spark however could be obtained on the knob of a small jar, there was not room enough for the induction to take place [[strikethrough]] in [[/strikethrough]]. [Repeat this on a larger scale, wire around room] Made an opening at [[underline]] a [[/underline]]: put in vessel of water. The lateral action was now very feeble. The electrometer placed at [[underline]] c [[/underline]] was opened for an instant, and then closed. When it remained permanently open, it was with a slight charge of [[image - positive sign]] elect. probably due to the small excess of the inner coating. This was shown by insulating the jar so as to leave about one 4th of one inch between the end of the long wire, and the bottom of the jar.
148 Jany 14th 1845 Lateral spark from long wire [[underline]] sun observed to day [[/underline]] [[image - experimental apparatus]] Made arrangements for getting the lateral spark from a long wire connected with the ground. First tried the machine without an increase of surface, - next suspended the plate covered with tin foil, - found an increase in the spark. - Next suspended the large conductor, found this gave the longest lateral spark. The wire was insulated except where it passed out of the window to descend into the wall at the corner of the building. Found that when the discharge 2 feet long was applied at different points along the wire no was was perceived unless occasionally a very [[?]] one. [[image across page]] Tried same exp with a wire of 4 feet long, same result - found no difference whether the wire was [[strikeout]] turned towards the machine, (the loose end of machine) or from it. Next tried the same experiment with a wire 8 feet long the same result was obtained. occasionally a spark passed, but generally none were perceived. With a length of equal 16 feet, the sparks passed freely nearly as much so as in the case of drawing the spark by the ball held in the hand, or when the connection was broken. [[end page] [[start page]] Jany 14th 1845 [[short squiggly line]] Lateral spark from long wire 149 According to the experiments of Mr Wheatstone, the duration of the charge is a perceptible wire as measured by the whirling mirror. The spark from the machine charges the wire and also its [[word circled]] appendices [[word circled]] [[image across page]] and hence since + is opposed to T, no spark passes or at most a very feeble one. I should think the tendency to pass a spark at a would be greater than at b the difference however on account of the shortness of the wire in comparison with the velocity of electricity. [[image across page]] Made a loop in the wire of four feet in circuit found that spark of about 1/10 of an passed between them. With another loop of 18 feet in circuit, the spark was nearly half an inch long. This result is not on circuit of the resistance to conduction, but because one part of the wire more highly charged than the other and acts on it by induction. the wire at the moment of passing the charge produced an induction on all sides as is shown [[image]] From all the experiments I have made on this subject there appears to be a marked difference between the action of a jar and the machine. I mean in the passage of the electricity from the positive to the negative side of a jar and in the passage of free electricity through a long wire. In the one case, the action begins at both ends at the
[[start page]] 150 Jany 14th 1845 / Condition of the discharging wire same time, and hence Mr Wheatstone found the spark to arrive last at the middle. To understand how this may take place, let a charged jar [[image]] be insulated, then at the instant the charge passes at [[underlined]]a[[/underlined]], the electricity is relieved at [[underlined]]b[[/underlined]], and a negative wave starts from the outside of the jar. But in the case of a long wire, the whole action is probably confined to one end, and is progressive through the wire from the plus to the negative end_ [[image - two wires with opposite positive and negative ends]] When two wires are placed parallel to each other, we may consider that during the discharge of the electricity through one of them from a jar, that a plus wave passes from the plus end towards the negative, and a negative wave in the opposite direction,and therefore on the princaple of induction, a minus wave should pass from the negative to the positive end, and a plus wave in the oposite direction, or in other words, the induced current should be opposite to that of the [[?]] current. [[image]] [[Note under image] NB in the first of these expts there was a break at [[underline]] d [[/underline]. [[End Note]] Arranged a wire in the form of a parallelogram 6 feet by 5, and across this at right angles fastened a wire [[underlined]]a b[[/underlined]], the ends of which [[underlined]]a[[/underlined]] & [[underlined]]b[[/underlined]] were rolled around a glass tube.. The jar was charged with the knob off, -the current was produced in the simple helix from the plus to the minus side of the wire, -or across from the part of the wire nearer the plus end to that nearer the other. [[end page]] [[start page]] 151 Jany 14th 1845 Condition of the discharging wire Repeated the same exp,. found the needles strongly magnetized with a current from the near part of the wire to the plus hole to the other extremity. This experiment differed from the last in the circumstance of the jars being insulated._ Repeated same experiment again, with the same result. needles all plus showing a current from the first end towards the other of the wire. The needle in the most convoluted spiral was the stronger showing no oscillation. Repeated same exp. with the exception of making an opening at [[underlined]]d[[/underlined]], so that the discharge should pass through about 1/4th of an inch of water._ All the needles were magnetic. Removed the jar, and made the discharge directly from the prime conductor of the machine. The needles in the small helix were magnetized. [[underline]]minus[[/underline]], the other two as in the previous experiment, [[underline]]plus[[/underline]]. This would indicate two currents. Repeated the last, all the needles slightly minus, current toward the first side. Again same result {These experiments indicate a progressive charge passing along the wire. Again charge stronger, compound spirals strongly [[underline]]plus[[/underline]], simple spiral minus,_ showing [[underline]]oscillation[[/underline]] Repeated same as last, results same + o -. Three spirals used in this exp. Repeated again, made the parallelogram more perfect._ Result however the same, the needles magnetized + o -. The more complex plus.
[[start page]] [[top margin]]152 Jany 14th 1845 Condition of a discharging wire[[/top margin]] Repeated the experiment with the jar - needles very slightly magnetized o- -- Opened the circut in the water at [[underline]]d[[/underline]], charge about the same, all the needles +++. Repeated last experiment, all things the same. all the needles +++ Repeated same with opening at [[underline]]d[[/underline]], closed needles, all +++, but not quite as strongly as in some of the other cases. These experiments conclusively show that the several parts even of a short wire, are not at the moment of the discharge in the same electrical state relative to each other. Also that there are oscillations from one end to the other. [[figure on left]] The last experiments were varied by bringing the ends of the middle of the cross wire nearly into contact. When the jar was discharged, a spark passed between the two points at [[underline]]a[[/underline]]. [[indent]] These exp, must be made with a larger rectangle. ----------[[/end indent]] The ends of the wire [[underline]]a[[/underline]] b may be connected with earth, and in this way the disturbed electry in the wire will be dischared in one direction, and probably, the needles will be more strongly magnetized. [[end page]] [[start page]] [[top margin]]Jany 15 1845 Examination of lateral spark 153[[/top margin]] Commenced farther investigation of the lateral spark from long wire. __ For this purpose, suspended the wire [[underline]]a[[/underline]] from the long wire by twisting one end around the wire, and hanging the other by means of a fine fibre [[figure from left, across page width]] of silk to the long wire, at the distance of 1/20th of an inch. When the machine was turned, sparks half an inch long could be drawn from the long wire, but no spark was observed to pass between the small ball [[underline]]a[[/underline]] and the wire. When the wire [[underline]] b' c'[[/underline]] was arranged, as shown in the figure, by suspension, a spark was passed at each point [[underline]]b'[[/underline]] c', but the affect was much increased by drawing at the same time a spark from the wire by means of the conductor [[underline]]f[[/underline]]. [[figure across page width]] When the discharging [[underline]]d[[/underline]] was in the position [[underline]]d[[/underline]], no spark passed at[[underline]]a[[/underline]], though large one passed at [[underline]]b[[/underline]], but when the same ball and wire were placed near the other end of the suspended wire as in the position [[underline]]d'[[/underline]], sparks passed. __ This is an illustration of the exp. given by Walker page For a paper relative to lateral discharge, see Nicholson's Journal 4[[circled]]to[[/circled]] vol 1, account of Van Marums machine. [[end page]]
154 Jany 15th Wednesday 1845 Lateral spark [[image]] (1) The induction of the spark shown by this arrangement,- a piece of glass placed at [underlined] a [/underlined] below an insulated conductor, and the wire. - sparks obtained at [underlined] d [/underlined]. [[image with the notation: 4 feet]] (2) Next made an arrangement of two needlepoint articles, joined by the wire c. When paper was placed between these points, it was constantly pierced so as to indicate a spark outward from each conductor. The sparks were of course much brighter when the rod [underlined] c [/underlined] was touched in the middle. [[image]] (3) Arranged two insulated conductors as shown in the figure _. No spark at the middle point [[underline]] a [[/underline]]. These conductors were of the same length and size - When the second conductor was placed so as to be in the prolongation of the first, then sparks passed in abundance between them. These experiments conclusively prove that the spark observed at each end of a lateral wire is not due to the division of the charge, but to a spark given off from the wire to each end of the conductor. [[End Page]] [[Start Page]] & 16th Jany 15, 1845 Lateral spark 155 The spark is not given off on account of the least resistance being in the direction of the lateral circuit, but because the force impelling [[strikethrough]] impelling [[/strikethrough]] it is greater in this direction. Next made exp. to see if the conductor in exp (1) on last page was permanently changed. The wire [underlined] d [/underlined] was insulated, and found after the spark + electrified. While the 1st conductor or that next the glass was in the opposite state * Jany 16th [[image with notation: about 9 feet]] Arranged 4 insulated conductors as shown in the figure, with openings ab. When the sparks from the large conductor were thrown on the ball [underlined] A [/underlined], bright spark were thrown off at [underlined] a [/underlined] and [underlined] b [/underlined], or I should say appeared at [underlined] a [/underlined] & [underlined] b [/underlined]. Next a wire nine feet long was hung from the wire [underlined] c d [/underlined]' by means of very fine silk fibre, sparks were seen to pass at [underlined] c d [/underlined], when spark from the large conductor were thrown on A [underlined]. [[image with notation: 3 feet]] Made the arrangement represented in the figure, - found in all cases that a spark [[strikethrough]] passed [[/strikethrough]] appeared at [underlined] b [/underlined] when the discharge was thrown on A. It would appear from this, that probably a spark passes in each direction. The spark appeared more brilliant the greater the distance the insulated conductors were apart. *From the fact that the conductor remains charge, it would appear that the dimenution of the [[strikethrough]]dis[[/strikethrough]]charge in the conductor is less intense than the increase [of the same.
156 Jany 16th 1845 condition of long wire-spark [[Image]] Made an arrangement similar to the last, and placed a magnetizer spiral at the opening [[underlined]] b [[/underlined]], found the needle unmagnetized._ Repeated same experiment with same result. Again the same experiment, the needle slightly magnetized with a [[underlined]] minus [[/underlined]] current, again same result. Again made the opening at [[underlined]] C [[/underlined]] much greater, needle slightly magnetized with a [[underlined]] plus [[/underlined]] current. Repeated same exp with same arrangement. Same result, current plus that is in the same direction with the current from the machine. [[Image with the notation: 25 feet]] Next made an arrangement as in the figure. In the middle of the secondary wire at [[underlined]] a [[/underlined]], a break was made, and into this was inserted a magnetizer spiral. The balls at [[underlined]] c [[/underlined]] and [[underlined]] b [[/underlined]] being placed at the distance of about 1/10 of an inch from the end of the conductors, the spark passed in each, and the needle was magnetized strongly in a [[strikethrough]] plus [[/strikethrough]] [[underlined]] minus [[/underlined]] direction. Repeated this experiment 6 times in succession, and always with the same results. Needle constantly magnetized in an adverse direction quite powerfully. [[End of Page]] [[Start of Page]] Jany 16th 1845 Lateral spark from long wire 157 Next brought the secondary wire at [[underlined]] c [[/underlined]] and [[underlined]] b [[/underlined]] incontact with the insulated conductors, [I called them insulated, they were however in contact with the wire], the needle was now magnetized by a [[underlined]] plus [[/underlined]] current. Removed the ball [[underlined]] b [[/underlined]] from the conductor to the distance of 1/2 an inch, while the ball [[underlined]] c [[/underlined]] was at the distance of about 1/10th of an inch, still the current as indicated by the needle was [[underlined]] minus [[/underlined]]. Next removed the same ball to the distance of a foot or more, and put my knuckle to the ball so as to draw off a spark, now the needle was magnetized with a plus current but not strongly. Placed the ball and conductor in contact at [[underlined]] b [[/underlined]] while they were 1/4 of an inch apart at [[underlined]] C [[/underlined]]. - Needle unmagnetized or very slightly affected. Next opened [[underlined]] b [[/underlined]], shut [[underlined] c [[/underlined]], now needle strongly magnetized with [[underlined]] minus [[/underlined]] current. [Singular result but in accordance with the others) Next removed the magnetizing spiral, and put in its place an apparatus for the pierced card, with this the current appeared to be both ways very near the middle, the hole was pierced a little nearing the farther point from the machine. Replaced the card apparatus [[strikethrough]] means [[/strtikethrough]] by [[strikethrough]] of [[/strikethrough]] the magnetizing spiral, introduced a darning needle, found it strongly magnetized by a [[underlined]] minus [[/underlined]] current.
158 Jany 17th 1845 [[figure along top of page]] Placed needle point in the direct course of the current, found the hole in the paper directly opposite the negative point. Next placed card at [[underline]a[[/underline]], found hole several times near the middle, but always nearer the point which would indicate a [[underline]]plus[[/underline]] current. Repeated the experiment with the card. constantly found the hole near the middle indicating a plus current but always near the middle. The result of these experiments would tend to show that there are two currents, the first one probably makes the hole, and the second passes through it. Next put needle apparatus at the end of the long wire [[underline]]b[[/underline]] and [[underline]]c[[/underline]]. The holes indicated first the preponderance of one and then of the other current. [[figure across width of page]] The above diagram gives the appearance of the holes from which I would infer that the plus current in the wire is a little stronger, but this does not certainly follow, since the plus current passes first and [[strikeout]]has a tendency to[[/srikeout]] pierces the hole through the 2nd current, also passes because there is least resistance. [[end page]] [[start page]] [[top margin]]Jany 27th 1845 159[[/top margin]] [[figure across width of page]] [[in margin]](1)[[/in margin]] Again put two magnetizing spirals in the course of the long wire, one at [[underline]]b[[/underline]], the other at [[underline]]c[[/underline]], both darning needles were magnetized with a minus current. Magnetism strong. [[in margin]]2[[/in margin]] Next the ball [[underline]]c[[/underline]] was removed to the distance 5 inches from the adjoining conductor, now the needle in [[underline]]b[[/underline]] was slightly magnetized by a [[underline]]plus[[/underline]] current. [[in margin]](3)[[/in margin]] Removed the wire and ball still farther from the conductor, the needle again magnetized by a [[underline]]plus[[/underline]] current [[strikeout]]but[[/strikeout]] stronger than that of the last, but still feeble. I suppose the needle is always magnetized by the minus current, because this takes place last, and it appears from all the experiments that a needle tends to loose its magnetism with a less force than that which magnetized it. The magnetic state is one of unstable equilibrium, and during the moment of passage of the [[strikeout]]needl[[/strikeout]] current around the needle, its intensity of magnetism is stronger than after the passage, in the same way that a magnetic bar under the process of magnetization is stronger while in contact with the inducing apparatus, whether it be another magnet or a galvanic spiral. Even a sudden jar will tend to weaken the magnetism. Hence a more feeble current than the one which originally magnetized a needle will be sufficient to reverse the polarity. [[end page]]
[[start page]] 160 Jany 17th 1845 Placed a large (darning) needle in [[ruige?]] spiral - sent small charge through - then charge of about the same intensity in the other direction, Magnetism reversed in the manner I anticipated. Make more exp on this point. [[Chart]] Needles magnetized by discharge of Franklin Battery [[on left side: Half needles N15]] No Distance Intensity 1 1/2 4° 2 1 15° 3 1 1/2 17 1/2 * 4 2 16 Battery 5 2 1/2 17 1/2 charged 6 3 12 1/2 about 40 7 3 1/2 11 8 4 3 9 4 1/2 7 10 5 4 11 5 1/2 0 [[Chart]] Exp 2nd [[on left side: Half needles No 15]] dist Intensity 1 1/2 -7 contact 2 1 +11 3 1 1/2 +18 * 4 2 17 1/2 5 2 1/2 16 1/2 6 3 15 Charge 7 3 1/2 13 45 8 4 12 9 4 1/2 7 10 5 6 NB The first needle in all these exp was in contact with the wine [[end page]] [[start page]] Jany 17th 1845 161 [[Chart]] Needles magnetized by Franklin Battery Exp 3rd. [[on left side: Half needles No 15]] No dist Intensity 1 0 0 2 1/2 16 3 1 20 * 4 1 1/2 19 5 2 17 1/2 Charge 40 6 2 1/2 16 1/2 7 3 12 1/2 8 3 1/2 3 9 4 3 10 4 1/2 0 11 5 2 [[Chart]] 4th Exp. [[on left side: Half needles no 15th]] No Dist Intensity 1 0 -5 2 1/2 33 3 1 25 4 1 1/2 32 5 2 36 6 2 1/2 35 Charge about 7 3 32 50° 8 3 1/2 28 9 4 26 1/2 10 4 1/2 26 11 5 24 12 5 1/2 20 13 6 15 NB These experiments were all made with 1/2 needles 1/15th part of an inch in diameter [[end page]]
[[start page]] [[top margin]]162 Jany Saturd 18th 1845[[/top margin]] [[Page divided into two tables, each surrounded with a drawn square border.]] Exp 5 [[first table, three columns]] no dist Inten 1 0 - 0 2 1/2 0 3 1 + 11 4 1 1/2 17 5 2 17 6 2 1/2 16 7 3 15 8 3 1/2 15 9 4 12 10 4 1/2 11 11 5 9 12 5 1/2 8 13 6 5 14 6 1/2 3 15 7 0 [[left margin]]needles no 15[[/left margin]] [[right margin]]Franklin and small battery. Charge about 40[[/right margin]] [[end first table]] Jany 18th Exp 6 [[second table, three columns]] No. Dist Inten 1 0 0 2 1/2 0 3 1 14 4 1 1/2 16 5 2 16 6 2 1/2 15 1/2 7 3 15 1/2 8 3 1/2 12 9 4 11 10 4 1/2 10 11 5 9 1/2 12 5 1/2 4 13 6 4 14 6 1/2 2 15 7 2 [[left margin]]Needles the same[[/left margin]] [[right margin]]Battery the same as the last[[/right margin]] [[/end second table]] [[end page]] [[start page]] [[top margin]]Jany 18th 1845 Magnetization of Needles 163[[/top margin]] [[The page is split into tables, similar to the previous page]] Exp 7 [[first table, three columns]] No dist Inten 1 0 15 2 1/2 10 3 1 6 4 1 1/2 2 5 2 2 6 2 1/2 0 7 3 0 8 3 1/2 0 9 4 0 10 4 1/2 0 11 5 0 12 5 0 [[left margin]]Needles same[[/left margin]] [[right margin]]Single jar[[/right margin]] Exp 8th [[second table, three columns]] No dist Intensity 1 0 + 28 2 1/2 + 34 3 1 35 4 1 1/2 32 5 2 31 6 2 1/2 30 7 3 28 8 3 1/2 26 9 4 24 10 4 1/2 24 11 5 22 12 5 1/2 20 13 6 18 [[left margin]]Needles same[[/left margin]] [[right margin]]Small square Battery of 8 jars highly charged One of the jars broke in the explosion[[/right margin]] [[/end of second figure]] NB In all these experiments, the discharge was passed through a wire of about 1/50 of an inch in diameter, and 3 feet and a half long. [[page end]]
[[start page]] [[top margin]]164 Jany 18th 1845 Return Stroke[[/top margin]] [[figure to left]] Made an arrangement like that in the figure, to repeat the experiment of Earl Stanhon on the return charge. [[figure extends from left, across width of page]] When the spark was drawn from the machine, the lateral spark passed at [[underline]]a[[/underline]], nearly an inch long and quite dense. When one hand was placed on the one insulated conductor, and the other on the other, quite a sever shock as from a small jar was felt. Also when the knuckle was approximated towards the conducting wire, leading to the wall, sparks were received. These were negative. Removed the large conductor, and merely used the two plates found the ^[[return]] spark in this case not quite as powerful as in the previous experiments. [[figure on left]] Next placed a ball 3 3/4 inches in diameter on the middle of the lower plate, a loud snap passed down, and [[figure extends from left across width of page]] a bright spark 3/4 of an long could be drawn from the long wire [[underline]]b[[/underline]]. When this was caught on the knob of the electrometer, the leaves were agitated, but did not diverge. [[end page]] [[start page]] [[top margin]] Jany 18th Returned Stroke and direct stroke confirmed 165[[/top margin]] Also when the apparatus for the pierced card was placed at the opening [[underline]]a[[/underline]], the induction was that of two currents. [[figure to left]] The holes were as represented in the figure, one at the middle, another a little near the pole next the machine, and two near the further end. These holes were however made by a number of sparks. [[figure to left]] Tried the same exp again several times, but now the hole was on the far pole, each time the machen however did not operate as powerfully as before, and before the charge of the upper plate took some escape took place. [[figure to left]] Next rubbed up the machine so as to increase the intensity of the induction, the spark was now directly in the middle! From these experiments, it appears as we might have supposed, that there are two waves, one from the direct stroke, and the other from the return stroke, and that these are in opposite directions. Hence, the unelectrified state of the electrometer after the knob had been presented to the long wire. The Induction which takes place in parallel wires, also takes place along the rail way, and probably in the ground, does this effect the fertilizing quality of the soil, are the induced subterranian currents sufficient in quality to produce decomposition? [[end page]]
166 Monday Jany 20th 1845 [[sketch in left margin]] Constructed this morning an electrometer with the silver leaves movable, and with this attempted to get a secondary current by motion of the secondary coil torn from the primary coil. When the motion was made, a slight divergency of the leaves was perceived when the secondary coil was raised from the primary, and an attraction when the secondary conductor was let down. When a spark was passed through the primary conductor, lateral sparks could be drawn from the secondary conductor similar to those from the primary conductor. From all the experiments I have thus far made, it appears that a conductor during the moment of its transmission of a current ,is charged at the point opposite the wave, in the same manner that a conductor is charge by free electricity and that induction takes place, and a spark passes in the same manner as in the case of statical electricity. The wave is not simultaneously in every part of the wire, but at different moments it is at different points. Also all the experiments indicate a difference in the action of a long wire transmitting a current from a large conductor, and one transmitting a discharge from a jar. See exp. 4, p 167. see page 154. [end of page] [beginning of page] Jany 21st 1845 167 1 [sketch in left margin] Repeated the experiment to procure a lateral spark from a secondary current with a jar from which the knob had been removed. 1st. When the knob of the jar was in place, [[strikethrough]] and [[/strikethrough]] and connected with the prime conductor of the machine, a bright spark passed between the two conductors. 2nd. When the jar was disconnected [[strikethrough]] with the [[/strikethrough]] from prime conductor, a spark passed, but less than in the other case. 3rd. When the knob was removed, still a small spark passed. 2 Repeated the old experiment of putting a large zinc plate between the primary & secondary conductor. -- Result the same as that I have published,-- bright spark at opening of secondary conductor without the plate, none with the plate interposed. 3 [sketch in left margin] Next repeated Priestley's exp. Made a bend in a wire 40 feet long at or near each end. Sent charge from one jar through, found that spark passed through full an inch of air. [[smaller text below]] see Priestley, page 349, vol. 2nd s-p 149 + 138. 4 Made the same exp with the same wire, and the free electricity from the large suspended disc, the spark was now not so long or so large as in the case of the jar. The direction as indicated by the [[strikethrough]] jar [[/strikethrough]] cur't was +. [end of page]
168 Jany 21st 1845 [[sketch at top, left margin]] (1) Coated glass tube of about 1/2 an inch in diameter with tin foil, sent shock from jar without knob through the tin foil, while a wire as shown in the figure made a current. found a secondary current in this way. [[smaller text]] Repeated this again, wire at right angles to the tube. [[/smaller text]] The direction of this current was the same as that in the experiment of two parallel wires, namely with a very small charge the needles were magnetized --, with larger charge +, and still larger o. The hole in a card was nearer the minus pole, but near the middle of the distance between them. (2) Tried to get a spark with the same arrangement by means of snaps from the conductor increased by the large plate attached, found a feeble spark. Needle very feebly magnetized +. The current in this case is combined with the induction from the inside of the tube, the wire acting as coating, hence the electricity will tend to be thrown off in each direction. This experiment (1) has a bearing on the experiment in which the electricity was shown to pass on the surface of a conductor. The feeble current in which I obtained in one experiment was probably due to induction. [[end page]] [[start page]] Jany 21st 1845 169 In the experiment of the electricity passing over the surface, use a very short tube, so that the induction may be small. [[line drawn across page]] [[sketch in left margin]] Placed small needles, made of knitting needles 5/8 of an inch long, and 1/36 of an inch in diameter on each side of a slip of tin foil [[underline]] a [[/underline]]. sent charge from battery through the foil, examined the needles, found them unmagnetic. This experiment belongs to those on the passage of electricity through a plate. [see page 100]
[[start page]] [[top margin]] 170 Jany 22nd 1845 [[three check marks]][[/top margin]] [[the top half of the page is filled with a figure consisting of 13 columns of offset numbers. The top-center label is "positive" and the bottom-center is labeled with an asterisk and "pole | negative"]] The above diagram exhibits the magnitism of a series of needles placed on a board covered with tin foil. The figures exhibit the deflection of the needles of the intensity apparatus [page ] caused by each needle. The needles were made of steel knitting, and the same as those used in the experiment mentioned at the top of the last page. The tin foil was ruled off into squares of an inch in size, and the centre of each needle was placed an inch from the line on which the adjoining needles were placed. From this experiment, it appears evident that the electricity spread over the whole surface of the foil. [[end page]] [[start page]] [[top margin]]Jany Monday 27th 1845 171[[/top margin]] [[figure along top width of page and down the right side]] Placed on the middle of the wire leading to the wall a piece of stove pipe 10 1/2 feet long and 5 inches in diameter. Sparks were drawn from this apparently as large as from the [[strikeout]]the[[/strikeout]] wire, but when they were measured by receiving them on a small jar, and applying them to an electrometer, they were found to be from 1/3 to 1/2 as large. This measurement was [[figure across centre of the page]] Next made made the apparatus, arranged an experiment with as in the figure. A square of glass being placed between the stove pipe and the conductor [[underline]]a[[/underline]]. When sparks were passed on to the ball from the large conductor, induction sparks passed from [[underline]]a[[/underline]] to [[underline]]b[[/underline]]. With the first spark the electrometer was diverged with the second spark, it was frequently collapsed, this effect was due to the tension of the electricity in the conductor [[strikeout]]be[[/strikeout]] becoming so great as to discharge itself at the moment of the second shock. [[figure]] Next grasped the wire firmly in the hand, while the spark was passing from the machine, [[strikeout]]were passing[[/strikeout]] but no commotion was perceived. When however the wire was loosely grasped then, a shock was felt _ When the wire was grasped by each hand tightly, no shock was perceived, no [[strikeout]]spark[[/strikeout]] sensation. [[end page]]
172 Mond Jany 27th 1845 was observed even when the tongue was pressed against the wire. This result is rather strange and requires some consideration, the tongue and the wire at instant were in the same state and hence no transfer took place from one to the other. When the hands were clasped around parts of the wire at a distance from each other, a commotion was expected to be perceived, but none was found. [[image - sketch of long wire attached to a jar]] Connected the long wire with the outside of an insulated jar, on the knob of which sparks were thrown - sparks were given off along the course of the wire as in the case of the direct spark. The spark in this case may be called that of the direct induction, and is the opposite of that which has been called the return stroke. When the jar was discharged, no shock was felt along the wire and no spark passed to the knuckle. [[image - sketch of long wire touched by hands noted as A and B]] Repeated the experiment of touching the wire when the spark passed through, found a slight commotion when the wire was held in the fingers, commotion more perceptible when the toung was made to touch the wire. When the knuckle of one hand was brought near the wire as at a, and the wire was grasped at b by the other hand, no sparks passed.- When the [[end page]] [[start page]] Jany 27th 1845 173 hand of another person was placed at b, the sparks passed at a - when the toung was applied at a, and the hand of the same body was placed lightly around the wire at b ,no shock was perceived, also when another person's hand was applied at the same spot, the shock was much less at a. This would seam to show an induction in advance, and by increasing the surface below, the tension is lessened above. [[image drawn across page]] Placed magnetizing needle in the axis of the large tube. sent through spark, found needle magnetized by a + current. Next placed same apparatus on the outside of the tube, needle stronger magnetized. The following are the results: Inside Outside NO diflec No difle 1 25 1 26 2 20 2 24 3 22 1/2 3 25 4 20 4 22 1/2 4/87 1/2 4/97 1/2 21. 7/8 24 3/8 N.B sparks on the outside were less in magnitude than those on the inside. [[image across the page]] Next placed the spiral used in the last exp. within a gun barrel well corked at the end, with tin foil. First exp gave the needle a magnetic
[[start page]] [[top margin]]174 Jany 27th 1845 Electricity passes on the outside of a tube[[/top margin]] of 12 1/2, but in this case the connection between the wire and the sides of the tube was not very perfect Next experiment gave the needle no magnetism The following are the results inside and out with the same intensity of spark each time [[Two tables placed side by side. For ease of transcription, I will record them separately, one above the other.]] Inside No Difle 1 13 2 0 2 0 2 0 2 0 ________ 5)[[underline]]13[[/underline]] 2 3/5 No Diflec 1 12 1/2 12 12 12 1/2 12 1/2 __________ 12 3/10 This result evidently settles the question of the tendancy of the electricity to pass along the outside. [[figure]] Repeated the same experiment with one spiral in the inside, [[strikeout]] an [[/strikeout]][[strikeout]]the[[/strikeout]] ^[[one]] other on the outside, with the same result, the one on the inside was unmagnetized. Repeated the exp by changing the spirals, the one on the outside was put on the inside, the result was the same. In [[?Mr.]], Knox's paper on conduction along the surface [[circled]]?[[/circled]]. See [[circled]]?Smith[[/circled]] [[circled]]ac[[/circled]]d 1829 vol 19, p 147. [[end page]] [[start page]] [[top margin]]Jany 27th 1845 Dr. [[circled]]OSchaunessey[[/circled]] experiments 175[[/top margin]] [[figure to left]] Attempted to repeat the expmt of Dr [[circled]]OSchaunessey[[/circled]] described in his letter to me, [[strikeout]]Oct[[/strikeout]] 8th 1843, but was not very successful. _ A piece of tin foil was placed on a plate of bees wax, and the discharge from the Franklin battery passed over it both in the dry and wet state flooded with water, and with the surface nearly moistened, but the effect described by the Dr was very faintly exhibited, if exhibited at all. The cause of failure was probably the level of intensity in the charge. Repeated with more success the other experiment mentioned in the Dr's letter-, [[figure to left]] placed lamp stand in the middle of a basin of water, and then discharged the Franklin battery. The discharge passed along 2 1/2 inches of the surface in preference to passing through one inch of water between [[underline]] a b[[/underline]]. When the Distance between [[underline]] c d[[/underline]] was made greater the discharge passed without explosion. I think there are some results like this mentioned in the american encyclopedia. This experiment is due to Priestley, see History of Electricity vol 2nd, 293. [[line across width of page]] [[figure to left and extending into the centre of the page]] Next made currents to illuminate a long wire by sparks from the machine, [[underline]]NB[[/underline]] I was surprised to find that the long wire to the wall became luminous. did not find that the two wires interfered as much as I had expected, but this effect was probably due to the great quantity of the spark. [[figure to left]] Try an arrangement like this. [[end page]]
[[start page]] [[top margin]]176 Jany 28th 1845[[/top margin]] [[figure to left]] Sent charge from Franklin battery through the under large disc to see if induction could be produced on the upper plate at the moment of the passage of the electricity, but the effect if any was very small. The electricity in this case was probably too much spread out over the whole surface of the plate, and consequently too much diminished in intensity to produce much effect. [[line across width of page, two hash lines in left margin]] If a discharge from a Leyden jar is sent through the vaccum of the air pump, the electricity is seen to spread out in streams filling the whole receiver, but if the same discharge is sent through a partial vaccum, the path is single and and not at all spread out. See Singers elect, also page of this vol. The fact above mentioned is important in showing the effect of the lateral pressure of the air. The spreading increases as the air is exhausted. If the hand be brought near the side of the receiver, the streams of electricity will be attracted or if a slip of [[strikeout]]?part[[/strikeout]] tin foil be pasted on the side of the outside of the receiver, the light will follow the line of this. These facts prove induction in the electrical current. [[end page]] [[start page]] [[top margin]]Jany 28th 1845 177[[/top margin]] spreading of an electrical discharge [[figure taking up much of the top half of the page. Top of figure is labeled Plus pole. Bottom of figure is labeled Minus pole]] Placed needles on the surface of the large disc 32 inches across, send shock through from Franklin battery, needles magnetized as in the diagram. NB I think it probable that in this experiment the circular disc of tin foil pasted on the opposite side of the board, and which had the position, indicated by the dotted line, had some effect in causing the needles on one side to be stronger than on the other. For a paper on the tendency of electrity to pass along the surface, see Trans Irish [[?]] vol 19, p 146, 1839. [[end page]]
[[start page]] [[top margin]]178 Jany 28th 1845[[//top margin]] [[The top half of this page is occupied by a large figure. The figure consists of a circle, labeled at the top with "Plus pole" and at the bottom with "negative pole". Inside the circle is a scattering of underlined numbers.]] [[beneath figure]] Repeated the last exp. Needles magnetized as in the diagram. [[end page]] [[start page]] [[top margin]]Jany 29th 1845 179[[/top margin]] [[Again, the page is much occupied by a figure. Underlined numbers are scattered in the shape of a hexagon, and surrounded by a rectangle. The top is labeled "Plus pole".]] [[beneath figure]] Placed needles on plate of copper of about 1/60th of an inch thick, 17 inches between the poles, and 14 inches wide. The needles on the edges were most strongly magnetized. [[underline]]NB[[/underline]] The needles on the out side of the pole were magnetized [[underline]]minus[[/underline]]. [[end page]]
[[start page]] [[top margin]]180 Jany 29 1845 [[top margin]] [[figure at top with image of copper plate and electrical poles]] Repeat this exp! Arranged needles on the outside of the two poles as in the diagram, found them all magnetized [[underline]]minus[[underline]]. This is an instructive experiment from which it would appear that the lines of current are similar to those on the surface of paper on which filings have been strewed above a magnet. [[vertical wavy lines to right and left of next sentence]] Refer in the account of these experiments to those of Professor Darrell on the divergency of a galvanic current. [[following citation in brackets]] Phil Soph Trans 1837 Next joined a wire [[underline]]a[[underline]] [[underline]]b[[underline]]leading to the well to the end of the plate at [[underline]]a[[underline]], the pole being as before, needle slightly magnetized with a current outwards. When larger needle* was placed in same spiral, no magnetism. Afterwards needle placed in spiral connected with [[d?]]. Magnetism small. * Darning needle [[end page]] [[start page]] [[top margin]]Jany 29 1845 181 [[top margin]] [[figure:plus and negative poles, gold leaf]] Sent charge of Franklin battery through gold leaf spread over the surface of a card of the size and shape represented in the diagram. The leaf was deflagrated around each [[strikeout]] [[?]][[strikeout]] pole, but more around the minus than the positive. The leaf was also more removed at the outer edges, than in the middle. The above sketch will serve to show the general appearance of the card after the explosion. When the sheets of gold overlaped, the metal was not deflagrated as as at [[underline]][[a]] [[underline]][[b]][[underline]] & c. [[end page]]
[[start page]] [[top margin]]182 Jany 29 1845[[/top margin]] [[The page is entirely occupied by a figure. Rectangle in shape with squiggly lines drawn throughout. The left hand side is labeled "Plus pole", and the right hand side labeled "negative pole".]] [[beneath the figure]] Covered pain of glass with gold leaf. Sent charge from Franklin battery through, Leaf destroyed around each pole, also cracks in it to the extremites of the plate to the right and left of the charge. [[end page]] [[start page]] [[top margin]]Jany 29th 1845 183[[/top margin]] [[figure beginning top left and moving across the page through the writing.]] Made arrangements to get induced spark from the return stroke, but found that athough the spark was produced and received on the ball of the electrometer, it did not produce much effect in diverging the leaves. Jany 31st [[indented and circled]]The second term of the college year commenced yesterday. My college duties after this will therefore prevent the continuance of my researches, except at intervals. [[/circled]] [[line across page width]] [[figure]] The above arrangement was made to exhibit the effect of the return strock, the spark at [[underline]]a[[/underline]] was 5 inches long. When a wire leading to the wall was attached to [[underline]]c[[/underline]], the spark at [[underline]]a[[/underline]] was not more than two inches [[strikeout]]and a half[[/strikeout]]. I should perhaps mention that the plates [[underline]]b[[/underline] + [[underline]]c[[/underline]] were insulated and connected by the wire [[underline]]d[[/underline]]. Sparks were passed on to a ball on the middle of the [[underline]]c[[/underline]]/ When the plate [[underline]]b[[/underline]] was removed from the influence of the conductor, the smark from [[underline]]a[[/underline]] was not more than 2 inches long. This is a combination of the direct shock ad the return stroke. [[end page]]
[[start page]] [[top margin]]184 Feby 1st 1845[[/top margin]] [[small figure to left]] Exhausted this evening the bulls eye, and sent sparks through the vacuum the separated, and when the rod of the bull's eye was placed about an eight of an inch from the conductor, a continued light almost filled the receiver. [[vertical in margin]]see page 95 + 6[[/margin]] The streams of light were attracted by my hands, thus indicating an induction action, but I did not succeed in exhibiting clearly a repulsive action between the streams and a charged conductor, or the knob of a jar presented to the streams on the outside of the glass. When the air was partially let into the vessel, and a shock sent through the partial vaccuum from a Lyden jar, the discharge was divided into two narrow streams, convex from each other never concave. [[small figure to left]] I have found in no case a tendancy of electrical discharges to attract each other as two galvanic currents do. I think the results which Mr Faraday imagined he perceived in the convexity of two sparks being towards each other, as an effect due to the passage of one of the sparks making way for the other. [[circled]]It would be an important experiment to try if two galvanic currents in a vacuum attract each other.[[/circled]] I allude to two galvanic currents such as are produced between two charcoal points. or between platinum balls. It is not probable that the attraction is due to the conductors. [[end page]] [[start page]] [[top margin]]Feby 5th 1845 185[[/top margin]] [[small figure to left]] Sent charge from one jar several times through through tin tube one inch in diameter and about a foot long, the enclosed needle was constantly found unmagnetized. Next placed the spiral on the outside, the needle was now magnetized. Next tried the same experiment with the same jar same spiral, but with a darning needle instead of the sewing needle I had before used. The same result was produced, the needle inside was unmagnetized while the one outside was rendered strongly polar. Again substituted for the tin tube a tube of paper of the same size covered with a coating of thin tin foil, with this thin conductor the needle was magnetized within. The experiment was repeated several times, and always with the same result. From the last result, it appears that when the electricity meets with resistance, it passes through the interior or in other words, when the thickness of the outer cylendr is not sufficient to conduct the whole charge without resistance, some passes along the wire in the interior. When a darning needle was placed in the middle of the tin tube, a slight dyne of magnetism was imparted to it by a discharge of the Franklin battery. [[end page]]
186 Feby 6th 1845 [[image]] Sent charge from battery through the gun barrel, found needle within slightly magnetized. {Franklin battery} When the jar of a foot and a half coating was used needle unmagnetized. Perhaps the connection between the conductors was not quite as intimate as might have been. Tried the same experiment with a short piece of gun barrel, again found the [[?]] needle slightly magnetized. From these experiments it would appear that although the tendency is to pass along the surface , yet where the quantity of electricity is great , it is induced to seek a passage through the interior in part. [[end page]] [[start page]] Feby 7th 1845 [[three checkmarks]] 187 Observed today that to exhibit to the class the experiment of a pierced card, the best article to use is a piece of coarse card board covered with white paper, such as the boxes are made of, in which the merchant keeps his finer articles ribands etc. When the outside is slightly moistened, where on each side of a quarter of an inch, was produced by the explosion tearing up the surface paper. [[image drawn in middle of paper of diagram. Annotation at top: Negative Pole. Annotation at bottom: Positive Pole]] [[written sideways on right margin]] NB shed on the powder with a small ball of cotton tied to a stick for a handle. Placed on a glass plate with a coating of tin foil on the opposite side a mixture of red lead and sulphurs. Passed a charge over this from two jars from the small battery around each pole, the powder was disturbed and electrical figures exhibited at each. The plus figures at the plus pole, the negative
[[start page]] [[top margin]]188 Feby 7th[[//top margin]] figures at the minus pole. I mean by these, such figures as are produced by touching the knob of a jar charged plus and then charged minus to the surface of the electrophorous, and then sprinkling over the surface the powder before mentioned. The electric discharge passed. visibly over the surface of the glass in three lines, the outer of which were convex outwards. Another fact appeared in these experiments, that the discharge appeared to pass over a greater surface of the glass under which was a plate of tin foil, the induction appeared to assist the passage. The induction of the charge would precede the discharge and accelerate its course. Also it was observed that in the case when the discharge did not pass *, the jar in all the experiments being insulated, the same figures were produced around the two poles. In this case, it is evident that the jar being insulated, the electricity started from . the knob [[strikeout]] case [[/strikeout]] on the plus side rendered the pole on the glass which corresponded highly plus, while the electricity at the same moment was drawn from the other rod, and rendered the adjacent pole highly minus. * on account of the distance of the poles [[end page]] [[start page]] Feby 7th 1845 189 The condition of things may be represented by [[image of drawing]] the figure here given. At the moment the spark started from the knob, a electricity was precipitated on the plate, and spread around [[underline]] b [[/underline]] , while at the same moment on account of the repulsion being relieved inside of the jar, the electricity passed from the wire [[underline]] d [[/underline]] into the outside of the jar, and drew the natural electricity from the surface of the glass plate, and thus gave rise to the configuration observed. From the appearance in the first mentioned experiment in which the balls were so close that the spark passed, it is evident that the same condition of things exists in the case where the discharge passes, although it cannot last but for the infinitely small part of a second. This experiment is an instructive one in the way of illustrating the action of the jar on the two ends of a long wire, the one being minus and the other plus. Repeated the same experiment twice again in succession, the same figures were exhibited. The red lead was accumulated around the negative pole,_ the sulphur around the other. The figure can only be seen distinctly when the plate is so inclined to the light that the angle of [[circled]] sundance [[/circled]] with the window does not reach the eye.
190 Feby 7th 1845 Repeated the experiment in which the balls were placed on glass without coating on the underside, and in which the explosion did not pass. The result was the same as before, around the plus pole the powder was marked like a star, and around the negative pole the marks were less distinct as if the powder had been blown off. Or perhaps I should state that the appearance around the plus pole was more rarified and [[circled]]brush[[/circled]]like than around the minus pole. Another phenomenon was observed in this experiment and in the similar one before tried, namely the glass plate without coating being placed on the dry board of the conductor, was strongly attracted by it, and when the plate was lifted up, the powder was thrown into confusion on account of the action of the liberated electricity which had been rendered latent by the proximity of the wood. In this case it appears that the discharge of the jar in passing over the surface of the glass rendered its under surface electrified, and on account of the partial conduction of the wooden plate, the induction was shortly communicated to it, and the two were therefore held together by the dissimilar electricities of the approximate surfaces. [[end page]] [[start page]] Febry 7th 191 Sent a discharge through a surface of iron filings sprinkled [[strikethrough]] battery [[/strikethrough]] thickly over a surface of glass. The discharge left on the fillings the marks of 7 distinct routs from one pole to the other, something [[image drawn]] like the figure in the margin. Threw off the free powder from one of the plates on which the figures of lead and sulphur wire depicted, and this way I obtained a complimentary picture, the glass was left free in broad lines around the plus pole, but in narrow ones around the other. Around the negative pole was a kind of double border. [[image of drawing]] Repeated the experiment described above in refer to the figure with the same result. Also found that by throwing off the red lead, a kind of complimentary figure was formed. Placed the poles on a piece of tin foil on which the sulphur and lead were strewed found no figures produced. Placed lycopodium on the table of the discharger, sent shock from jar through, powder flashed into a blaze.
[[Start page]] 192 Feby Saturday 8th 1845 Placed on the negative side a vessel of water so as to retard the electricity on that side, with the idea that a smaller circle might be produced [[strikethrough]] on [[/strikethrough]] around the negative pole, but found no difference of much note if any . Also placed the jar in connection with the earth on the negative side, but the result was the same. Sent the discharge again through iron filings on a glass plate. The space between the poles was marked with 8 [[circled]]traces [[/circled]] indicating as many passages of the divided discharge In discharging the jar through a slip of tin foil, I observed the effect described by Priestly, vol 2 p272, of a pole surrounded with a coloured circle. Priestley throws out the idea that this effect is produced a series of concentric cylindrical discharges without understanding any thing of the nature of dynamic induction, he has here thrown out an idea which I think is a true one. [see my exp page 168] [[line drawn across page]] [[image of drawing]] Made a rectangle of wire as in the figure, placed a latteral wire as [[underline]] b [[/underline]], charged spiral with small needle no 6, sent shock in the direction of arrow ,- needle magnetized in opposite direction. Repeated experiment several times with darning needles, result the same, current reverse. The charge considerably great. [[end page]] [[start page]] Feby Saturday 8th 1845. 193 1 Repeated same experiment with a small charge, needle magnetized [[underlined]] direct [[/underlined]]. same result with a darning needle on one occasion before. 2 Repeated same exp., charge about 3 times as great needle [[underlined]] inverse. [[/underlined]] 3 Made an opening at [[underline]] b [[/underline]], grasped the two ends of the wire in my hands, but could feel no effect. 4 Again the experiment was repeated with pierced card apparatus,- first result indicated a current direct second in the middle. [[image drawn across page]] 5 Arranged the apparatus to send spark along long wire to the wall ,while a fine wire was suspended parallel to the first. The needle placed in the magnetizing spiral at was magnetized by a [[underlined]] direct [[/underlined]] current. The needle used was a darning needle, experiment repeated, all things the same , result the same. Repeated same with small needle, the result the same. These results are in accordance with those with the jar given at the top of the page. With a large charge, the current was inverse, with a small direct. Repeated the above experiment with small distance of wire , that is instead of the lateral wire having a length of 10 or more feet,it had about 4 feet,the effect was the same. [Jany 11th 1845]
194 February 10th 1845 Monday [[diagram, bottle with wires coming out to the right, some circles and connecting to a pair of wires labeled a and b]] Sent discharge through two narrow slips of tin foil fastened loosely between two balls. At the moment of the discharge, the slips clapped together, during the progress of the charge they gradually appeared to separate, although I touched them to draw off any charge of free electricity which might tend to cause them to repel each other. The effect was in all the same, the leaves constantly clapped together. The effect however is not improbably due to the commotion in the air produced by the passage of the discharge. Repeated same experiment in the vacuum [[image drawn]] of the air pump with the buul's eye apparatus, but now the effect maintained above was not exhibited. The leaves appeared unaffected by the discharge. I therefore think it probable that the result obtained before was due to the sudden agitation of the air between the two slips. Repeated the last exp again with the same result, no appearance of attraction was exhibited. [[image drawn]] The end of the slip at b was in contact or very nearly so with the ball a, at the moment of discharge a spark was seen at b, and the end of the slip thrown off so that the whole oscillated and struck the ball several times. This effect was probably due to the small quantity of air in the jar which was suddenly expended. If the same effect were produced in a Toricellian vacuum it would indicate the consecutive repulsion I have mentioned in one of my papers. [[end page]] [[start page]] Feby 10th 195 For remarks on lateral explosion, see Priestley History of Elect vol 2 (my copy) p338 etc. By lateral explosion, he understands the throwing off from the line of discharge, all light bodies which happen to be there. This is different from the lateral discharge. He sais that the immediate cause of the dispersion of bodies in the neighborhood of electrical explosions is not their being suddenly charged with a quantity of electrical matter and therefore flying off from others that are charged, is evident from the following experiments. 1 No attraction was observed. 2 The explosion made ever so near a brass rod did not so much as disturb the equilibrium of the body with balls unaffected. The effect of the lateral force was evident through thin substances of various kinds. When grains of powder were put into a thin spiral stopped and held near the explosion of a battery they were thrown into agitation. He thinks the effect is produced by the agitation given to the air which affects the bodies by agitation on the opposite side of the glass. The only objection to this hypothesis is that the effect was not so much less in a vacuum as might have been expected. Both induction and agitation of the air were operative in the production of these phenomena.
196 Febry 11th 1845 [[image]] 1 - Made an arrangement for getting the electrical figures with the large conductor, and the wire going to the wall. Frst, the glass was without coating on the under side, and in this case, the figure was formed around the plus pole alone. 2 - Next the powder was sprinkled over the plate of glass coated on the lower side with tin foil, with this arrangement the figure was produced at each pole the same as in [[image]] the case of an electrical jar. 3 - Repeated the experiment with the uncoated glass with the same result, the figure was exhibited only at the plus pole. 4 - Tried the same experiment with the jar, and the uncoated plates formed the result the same as with the large conductor, the figure was not produced around the negative pole. This is not in accordance with the result of the first exp p 190. In this case however, a small jar was used, while in the other, one of the tall jars of the small battery was employed. also in the above experiment, I found that the large conductor was connected with the machine. [[end page]] [[start page]] 197 Febry 11th 1845 The rationally of the effect in exp No 2 last page, appears to be that the charge in [[advery?]] by induction renders the tin foil under the glass strongly negative under the minus pole, and the electricity [[strikethrough]] fo [[/strikethrough]] under the plus pole is driven out on all sides. Repeated the experiment with the small jar and the plated and the unplated glass, I should say coated and uncoated, with the first, the spark passed over a distance of four inches, with the latter it would not pass over a distance of more than two inches, this clearly establishes the fact that the coating of a pane of glass on one side favours the passage of electricity over the other, induction of an opposite kind takes place, which must precede the charge and assist in its passage through the air. ^[[See observations on the passage over the surface of water 175p]] Tried to produce the figures with three jars, but did not succeede very well. The jar reqiers to be manually charged to produce the effect well. When the conducting rod was brought in contact with the knob of the battery, the discharge did not pass at the first attempt, but a small quantity of the electricity was drawn from the inside, which instantly produced an effect at each pole on the plate, an effect evidently due to the reversal of the tension from the inside which drew the electricity from the negative pole.
[[start page]] 198 Feby 11th 1845 [[squiggly vertical line]]Stain on glass by discharge Observed to day on the neck of a jar over which a spontaneous discharge had passed, a perminent stain of a bluish color marking the track of the discharge, both on the inside and the out side of the jar, but the most surprising fact relative to this trace, is that it appears to be double throughout its whole length. [[hand-drawn image of jar top with snake-like line vertically through the middle, taking up left side of page, notes go around the illustration]] This phenomenon I found mentioned by Mr Etrick in a communication to the British Association, see Sturgeons Annals Vol 2 p 39. [[horizontal hand-drawn line across page, sep. top from bottom]] [[image of drawing]] Placed on the table of the descharger, a piece of French plate flint glass and sent a number of descharges over the surface of this between the two steel points of the descharger, first with one jar then with two, and lastly with three & four. Each discharge made a trace [[image of drawing]] of which the figures give some idea. each trac, when viewed with light indirectly reflected, showed a broad bluish stain on the glass with a lighter blue in the middle. The whole was evidently one trace with a more intense action along the edges, or it might be due to an induction action along the centre of the track. When the trace was viewed with light reflected from the window spectrally, then the colour was a beautiful green, bordered on the edge with blue and [[strikeout]] in the center with [[/strikeout]] an orange line along the centre. [The figures above are about 1/3 larger than reality] Tried the Franklin battery, but did not succeed in making much of a mark, the discharge appeared to pass principally through the air, and only decend to the glass in the middle between the two points. [[end page]] [[start page]] Feby 11th 1845 [[short squiggly line]] Trace on glass etc 199 When trace No3 is placed on a black ground, and the eye perpendicularly above it before a window, it exhibits three light blue lines throughout its whole length precisely parallel to each other, and seperated by two darker lines, see figure in which [[image drawn]] the white should be the darker, and the three darker the light blue. As I have stated before, the surface presented when viewed by reflected light, a beautiful green colour, I should add to this, that the appearance of this surface was evidently metallic. [[image]] Sent charge from two jars over surface of mica. a continuous mark was made between the points with little or no variation across it. Next passed discharge from two jars over paper covered with vermillion placed on a plate of glass, the glass was stained with the reduced vermillion, and reduced to the metallic state, and in one experiment [[image]] an apparatus like that in the figure was exhibited, the metal was produced along the path on each side of a middle track, which was entirely clear, the glass could along this be seen through, as if along this line the reduced metal had been blown off or deflagrated. Placed under the glass a piece of tin foil, so as to assist the conduction, with this the trace with two jars was an inch and a half long, and very distinctly marked, two jars well charged being used. [[end page]]
200 Feby 12th 1845 Send a charge from two jars over the surface of the table of the universal discharger which was covered with a varnish of vermilion. The metal was reduced along the sides of the track, but did not appear in the middle of the same along which the red colour of the vermillion was perceptible. [[image drawing]] The figures represent the appearance on the table the dotted part in the metal reduced from the vermillion. [[line across page]] [[image across page]] Placed a small conductor near a break in the long wire, leading to the wall, passed sparks from the long conductor, found the small conductor electrified by induction, although a square of glass was placed between. I have tried this experiment in the case of the Leyden jar. [[end page]] [[start page]] Feby 18th 1845 [[underlined]] Spot on the Sun [[/underlined]] 201 [[image drawing]] Mr Alexander informed me yesterday there were several spots on the sun, and among them number one of unusual magnitude. We accordingly prepared to repeat our experiments on it with the same arrangement as that described page ^Jany 4th^ 131. The sun was not perfectly clear, but occasionally covered with a slight haze. The indications were the same as before, but the differences less. This was probably the result of the action of the pile and the temperature of the room. [[written on left side of list]] with compound eye piece [[/written on left side of list]] spot 2 sun 2 1/2 sun 2 1/2 sp 2 sun 3 sp 2 spot 2 1/2 sun 2 1/2 spot 2 1/4 sp 3 sun 2 3/4 sun 4 sun 3 sun 3 sp 2 1/4 sp 2 1/4 sp 2 1/4 sun 3 1/4 [[written on right side of list, bracketing the first four entries]] with compound eye piece [[/written on right side of list]] [[written on right side of list, bracketing last 4 entries]] with eye piece of single lense [[/written on right side of list]] Made a few observations on the centre and limb, but our time was too limited , Mr A was called away to meet his class.
[[start page]] [[top margin]][[check mark]]202 Feby 18th 1845[[/top margin]] [[figure]] To show that the jar without knob is without extra quantity, made this arrangement. Small jar placed near the line joining the centres of the two balls of the universal discharger. Sent shock through, then examined the then small jar from it had retained no electricity, although the spark had passed in and out of it! When the knob was put in the jar, the small jar was electrified plus or minus according as one or other of these conditions existed in excess in the jar. [[drawn line across the width of the page]] [[figure of circuit with writing throughout]] Made experiments on long wire around the room with jar without knob, found spark [[underline]]c[[/underline]] and [[underline]]d[[/underline, but none of [[underline]]a[[/underline]], but each of these sparks appeared plus _. There may however been some mistake in this. The wire was 45 feet by 24, while length 158 feet. Tried several times, always same. [[/figure]] [[small script beneath figure]] The jar was insulated on beeswax.[[/end small script]] [[beneath figure]] Next made a break in the wire at [[underline]]a[[/underline]], and placed there a tube full with water, so as to retard the discharge. Now I obtained on two occasions the last one of was attended with the breaking of the glass tube, spark of considerable apparent intensity and quantity, but which did not affect the galvanometer, they were the oscillating sparks of Priestley. [[end page]] [[start page]] [[top margin]Feby 18th 1845 [[check mark]]208[[/top margin]] I gave a lecture this evening on electrical lights and in exhibiting the experiment of passing the spark through the vessel called the bulls eye, from which the air was exhausted, I again saw the light spots in the beams which I have mentioned at page. On inspecting these closely, they appeared to be produced by the crossing of two rays, the point of intersection giving to the eye a double impression. This effect would be the same whether the beams were simultaneous in their passage or successive, provided as is the case in the electrical discharge of this kind, that the two followed each other at a less interval of time then 1/10 of a second. On Saturday night, Feby 15th, we had a very violent storm of rain accompanied with thunder and lightning. The lightning struck a house in New York, and according to the newspaper account, produced some wonderful effects. I afterwards visited this house, found that the account in the newspaper was an [[?exagricited]] one. Is stated that as the discharge passed along the wall of a room against which a bed was placed, that the latter was thrown into the middle of the room. The servant maid of the house informed me that she had herself moved the bed into the middle of the floor to prevent it being injured by the falling plaster. [[end page]]
[[start page]] [[top margin]]204 Feby 21st 1845 [[underline]]Capillarity[[/underline]][[/top margin]] [[margin]] p 140 [[/margin]] Inspected this morning the lead wire which I placed in a perpendicular position on the 10th of Jany, see p 140, with its lower end in a cup of mercury. I found that the process of elevation had apparently been going on continually, and that the mercury had reached the elevation of 14 inches above the surface of the liquid metal in the cup. The elapsed time being 42 days, the elevation has been at the rate of exactly 1/3 of an inch per day on the average, and this is very nearly the same rate with which the elevation commenced. I also found that the lead syphon which had previously been used for the transmission of the mercury, still continued to transmit it, but the progress was excedingly slow. While all the mercury was drawn out of the cup with new wire in the course of a few days, but a small quantity has passed up to this time through the other syphon. I think it probable that the suggestion I have thrown out at page 141 is true, namely that a permanent and stable compound is formed after a time between the lead and the mercury. Mr Eckfelt of the Mint has promised to make some experiments for me to determine whether gold in a deep crucible which has been suffered to cool gradually, will be found to contain the same amount of alloy at the top and bottom. [[end page]] [[start page]] [[top margin]] Feby 21st 1845 [[check mark]]205[[/top margin]] Repeated the experiments given at Page 202 with the long wire around the room,_The only difference in the arrangement was that ^[[end]] of the wire which communicated with the out side of the jar did not come in contact with it by a distance of about half an inch, inorder after the manner of Priestly to neutralize the, or I should say, equalize, the electricity of the two sides. [[margin]]Exp 1.[[/margin]] In the first experiment, quite a bright and large spark passed to the knob of the small test jar, which however did not affect the electrometer, It was one of the oscillating sparks. [[margin]]Exp. 2.[[/margin]] [[figure]] In the second experiment, the wire inorder to render it steady, was placed over an insulated conductor, and the test jar brough nearly in contact with this. With this arrangement, quite, a large spark passed to the knob of the small jar, which electrified the electrometer quite sensibly, say 10 degrees and more, with a [[underline]]minus[[/underline]] charge. [[margin]]Exp. 3.[[/margin]] Next the conductor [[underline]]a[[/underline was placed in contact with the plus end of the long wire, and the same experiment repeated, the spark was again large and now was found to be [[underline]]plus[[/underline]]. [[margin]]Exp. 4[[/margin]] Again placed the test jar at [[underline]]a[[/underline]] page 202 the middle of the wire, but could not perceive the slightest spark, although the experiment was repeated three times in succession. [[end page]]
[[start page]] [[top margin]][[check mark]]206 Feby 21st 1845 Late spark from different ends of wire around the room[[/top margin]] [[margin]]Exp. 5 [[strikeout]]1[[/strikeout]][[/margin]] Repeated same experiment, found the spark at the out part of the jar. several times in succession, give no charge to the electromete and then again a [[underline]]plus[[/underline]] charge. [[margin]]6[[strikeout]]2[[/strikeout]][[/margin]] Repeated the exp again, found the spark at outside minus. Spark in the preceding discharge at the other end plus. In this experiment I removed the end of the wire a little farther from the end of the jar. [[margin]]7[[strikeout]]3[[/strikeout]][[/margin]] Repeated the last with the difference that one jar was held near the conductor connected with the [[underline]]plus[[/underline]] end, and the other at the same time near one connected with the [[underline]]minus[[/underline]]. The two jars appeared both charged and with different kinds of electricity. [[line across width of page]] [[margin]]8[[strikeout]]4[[/strikeout]][[/margin]] Next made a break of about 1/4 of an inch in the wire at [[underline]]a[[/underline]], with arrangement. The spark at the [[underline]]minus[[/underline]] end was several times without effect on the electrometer and once strongly [[underline]]plus[[/underline]]. [[margin]]9[[strikeout]]5[[/strikeout]][[/margin]] Repeated the same both sides or ends I should say were [[underline]]plus[[/underline]]. A conductor was used as the receiver at the outside end of the wire, and the small test jar at the other. [[line across half the page width]] Closed break at [[underline]]a[[/underline]] [[margin]]10[[strikeout]]6[[/strikeout]][[/margin]] When the knob of the jar was put in place, and the discharge made through the long wire, a bright spark was caught on the small jar at [[underline]]a[[/underline, showing conclusively the difference [[end page]] [[start page]] [[top margin]] Feby 21st 1845 Lateral spark from wire around the room 207 [[checkmark]][[/top margin]] between the action of the jar with and without the knob. [[margin]]Exp. 11[[/margin]] Removed the end of the wire next to outside still farther from the tinfoil of the outside of the jar, nearest distance being about an inch, with this, the spark, to the small jar was quite large, but it did not affect the electrometer. The spark in this case was from the negative end of the wire. I found that in the exp the wire touched the table which might have [[margin]]Exp. 12[[/margin]] Repeated the same, electrometer feebly affected with apparently + electricity. [[line across width of page]] [[margin]]Exp. 13[[/margin]] Repeated same, jar held to the [[underline]]plus[[/underline]] end, electrometer strongly elect [[underline]]plus[[/underline]] again plus end + strong [[underline]]minus[[/underline]] end + feeble [[underline]]minus[[/underline]] end + feeble plus end + tolerably strong minus end + feeble plus end + feeble [[curly bracket surrounding first 5 rows of above table]][[text vertical in margin]]end of wire distant from the outer coating 1 1/4 inch[[/text vertical in margin]] [[margin]]Exp. 14.[[/margin]] Next made break in the wire [[underline]] at a[[/underline]] of about 1/2 an inch, end of wire in contact with outside of the jar. Bright spark, but no effect on [[faded underline]]elect[[/faded underline]] [[right margin]]end minus[[/right margin]] Repeated same, bright spark, no effect on elect [[right margin]]minus end[[/right margin]] Again with the [[underline]]plus[[/underline]] end, no effect. [[margin]]Exp. 15.[[/margin]] Next opened the separation in the wire to the distance of an inch. Bright spark on negative side, elect unaffected. [[end page]]
208 Feby 21st 1845 { Lateral spark from long wire around the Room } Exp. 16. Again very bright spark on [[underlined]] plus [[/underlined] side, electrometer unaffected. [[hand drawn line across page, indicating wires, broken in middle with - on left side, + on right, underlined 'a' above, with a tube with small circle on top below]] Exp. 17. Next placed the knob of the small jar at [[underlined]] a [[/underlined]], mid way between the ends of the wire. The spark passed to the knob of the jar, and off again to the end of the other wire, or in other words it took the knob in its way, but although the snap was loud and the spark brilliant, the jar did not receive the least sign of electricity-, this is an interesting result. The distance of the two ends of the wire was an inch and three quarters. The minus end of the wire was in contact with the out side coating of the jar. Exp. 18. Repeated same exp, jar slightly charged plus. The spark in this case did not leave its line of direction. Exp. 19. Repeated again, spark deviated, no charge to the jar. Exp. 20 Repeated again, held the ball of the jar near the + side of [[underline]] a [[/underline]], the electrometer was now affected with plus electricity. Exp. 21 Next Repeated the same, held the knob near minus side of the opening, electrometer unaffected. In this exp I found that the end of the wire was moved from the outside of the jar an inch. Exp. 22 Repeated same, put ball of jar near minus side of [[underline]] a [[/underline]] ; found charge [[underlined]] minus [[/underlined]]. Exp. 23 Again same as the last jar [[underlined]] uncharged [[/underlined]]. [[end page]] [[start page]] Feby 21st 1845 { Lateral spark from long wire around the room 209 [[image - hand drawn line across page, indicating wires, broken in middle with - on left side, + on right, 'a' above]] Exp. 24 Again jar on the plus side, jar charged [[underlined]] plus [[underlined]], in this exp. a lateral spark appeared to be given off to the jar. Exp. 25 Repeated the same, again jar on the negative side of [[underline]] a [[/underline]] ,charge seemingly affected the electrometer, and if any thing it was [[underlined]] minus [[underlined]]. Exp. 26 Repeated again, jar very slightly [[underlined]] minus [[/underlined]] on minus side. Exp. 27 Again jar in middle of opening [[image - Two short horizontal lines with a small space between depicting wires. The left wire has a knob on the right end and the right a knob on the left end. Between and below the space between the wires is a jar with a rod with a knob end extending upward between the wires. There are two dashes in the space between the knob of the jar and knobs of the wires.]] no charge was received, although the spark passed through the knob. Exp. 28 Repeated again, jar at the negative side, no charge. Exp. 29 Again jar placed on plus side, charge very slightly plus. In this case the discharge was full and instantaneous, but in some cases the discharge appears partial, and then of course the jar should be charged [[underlined]] plus [[/underlined]]. There should be a preponderance of [[underlined]] plus [[/underlined]] charge in all these experiments, because in charging the jar, there was always a slight excess on the inside, because the jar was not a perfect sphere, or rather because it was not a sphere enclosed on all sides, as it should have been on the supposition of a perfect neutralization. [[image - small line]] Repeated these experiments with a more delicate electrometer, the one of silver leaves had been used in all the experiments of this year until now. - I had gold leaf electrometer returned this morning.
[[start page]] [[top margin]][[checkmark]]210 Feby 21st 1845 Return Stroke[[/top margin]] [[figure midway along top of page]] [[left margin]]Exp. 30[[/left margin]] The knob of the jar was placed on the negative side, the charge was slightly [[underline]]plus[[/underline]] [[left margin]]Exp. 31[[/left margin]] Again on the negative side, it was [[underline]]minus[[/underline]]. [[left margin]]Exp. 32[[/left margin]] Again held the knob mid way between the two ends, no charge was received. [[left margin]]Exp. 33[[/left margin]] Joined the two ends of the wire, presented the knob of the test jar, no spark. [[left margin]]Exp. 34[[/left margin]] Repeated the experiment again with ends joined, but could not in any case procure a spark. [[line across width of page]] [[figure spanning width of page]] Connected large plate with the electrical machine, and placed the other under it at the distance of about 5 inches, made the arrangements with the two brass conductors, which is shown at [[underline]]a b[[/underline]] in the figure. When a spark was drawn from the machine at [[underline]]c[[/underline]], and a hand of each arm placed on [[underline]]a b[[/underline]], a slight shock was felt, the spark which was drawn from the machine was a small one, and in several parts like these drawn from a jar, of which the one side only is touched, in this way no lateral spark could be obtained when the two conductors were together, but when they were separated and then the machine turned until the upper bound was charged, then the wheel stopped and the spark drawn, a lateral spark [[end page]] [[start page]] [[top margin]] Feby 21st 1845 Lateral spark from the return stroke 211[[/top margin]] was obtained at [[underline]]d[[/underline]], which when tested by the electrometer was found to be[[underline]]minus[[/underline]]. While the upper [[strikeout]]spark[[/strikeout]] board was charging, a series of sparks were sent off in the opposite direction, and care was required that the jar was not charged with one of these. I would give the name [[underline]]negative[[/underline]] wave to one which charges the ^[[test]] jar minus, and the name [[underline]]positive[[/underline]] wave to a discharge which gives a positive charge to the jar. The term wave appears applicable, because the charge occupies but a part of the length of the conductor at the same moment of time. When the discharge C E connected the under plate, and the upper one of the machine, which amounts to the same thing, the lateral sparks were [[underline]]plus[[/underline]], and the shock between the two conductors stronger. In this case, there was without doubt an oscillation of the electricity. [[line drawn across the width of the page]] [[figure at left]] Placed a ball on the end of a wire on the lower plate, threw sparks on this from the upper plate. While a small rod with a ball on the end was placed near the rod, it being insulated on glass, no lateral spark passed, except was was due to the induction sending the electricity of the horizontal rod out into the perpen one, at the moment of the passage of the spark, no spark passed. This appears to be a good representation of the conduction of the lightning rod. When the ball was placed on the outside of the lower plate, a much larger spark passed. In this case, there was probably the return stroke, and the direct stroke combined, but by this arrangement the direct stroke must always predominate. [[figure]] [[end page]]
[[start page]] [[top margin]] [[checkmark]]212 Feby 21st 1845 Induction of the two ends of a wire[[/top margin]] [[figure]] Made an arrangement represented by the above sketch, in which a represents a jar with the knob removed and insulated, [[underline]]b[[/underline]] & [[underline]]c[[/underline]] two brass insulated conductors. When these were connected with the plus and minus end of the long wire ^[[suspended]] around the room, and the two extremites brought within about a quarter of an inch of each other, a vivid spark passed at each discharge. The extremities were next placed at about an 1/8 of an inch apart, and a pane of glass placed between, with this arrangement a bright flash was seen to pass to each side of the glass, and [[circled]]?correscate[[/circled]] on each surface. The effect in this case was very beautiful, the experiment was made in the twilight. The pane of glass was next removed, and a small jar substituted. A brilliant spark passed between the knob and the adjoining [[asterisk in margin]] conductor, but the jar exhibited no charge, or at least a very feeble one, due to the want of perfect equality in the electricities on the two sides of the glass. [[within large square brackets]]I always get a spark at each end of the wire, but by this arrangement we get the effect due to each, and at the same time or a double effect.[[/close brackets]] [[end page]] [[start page]] [[top margin]]Feby 21st 1845 213[[checkmark]][[/top margin]] The results on the last page appear to me to be important in reference to the question of the conduction of the two halfs of the conducting wire, and they are readily explicable on the hypothesis that at the moment of the beginning of the discharge, the one conductor [[underline]]b[[/underline]] partakes of the electricity of the end of the wire in contact with it and is plus, and accordingly sends a charge into the outside of the jar, which tends to send a charge from the ball into [[underline]]c[[/underline]], but c at the same moment is [[underline]]minus[[/underline]], and tends to attract the electricity out of the knob of the jar, These two actions combined, produce the brilliant spark at [[underline]]d[[/underline]]. But the moment after the spark has passed, the conductor [[underline]]b[[/underline]] returns to its natural state and also c, and consequently the jar will discharge itself through the same channel, which was produced by the rupture of the air in the first passage, since both effects probably take place in less time than the air requires to fill up the vacum. The [[strikeout]]case of the[[/strikeout]] discharge is different in this case from that which would be produced by bringing a jar, or rather the knob of it near a charged conductor, a very feeble spark would only pass in the air, but how we suppose the one body neutral, [[strikeout]]and[[/strikeout]] the other positive, and a vacum between them. If in addition to this we admit an oscillatory motion in the discharge of the jar, [[strikeout]]why[[/strikeout]] the effect should be still greater, and the jar more completely charged. It is necessary to admit the simultaneous + + - states of the two ends of the jar, in order to explain the want of spark at the middle. [[end page]]
[[start page]] [[top margin]] [[checkmark]]214 Feby 22nd 1845 [[handwritten squiggly vertical separator]] Continuation of the last exp.[[/top margin]] [[image - sketch of the jar with conductors, similar to p. 212]] Repeated the experiment of last night with the jar between the knobs of the two conductors, but I used a larger jar, one containing about a pint, with this the snap was quite brilliant and half an inch long, although the jar did not affect the electrometer in the slightest degree. This is a very striking experiment. I next placed one side of the jar in connection with one of the conductors, while the other side of the jar (I mean coating),was in contact with my hand,and another part of the same hand in contact with the other conductor. When the discharge was sent through the long wire; my hand received a violent shock, although the jar was the small one which I have called the test jar. The circuit was afterwards shortened so as to be about from 18 to 20 feet in length, with this the spark was produced as in the other case and with nearly the same intensity. Next shortened the circuit to about four feet, still the spark was produced, but apparently with not quite as much intensity as with the long wire. Repeated the same exp with a gallon jar, the spark was brilliant, but perhaps not much more so than with the smaller jar. [[images of four figures]] [[end page]] [[start page]] Feby 22nd 1845 215 Tried the same experiment with the knob of the jar in place, and connected with the machine, so as to produce a quantity of free electricity in the current, but the result was about the same, the pint jar received a bright spark and afterwards exhibited but a trace free electricity. [[line drawn across page with image of drawing]] Placed a plate of glass coated on one side in the middle of the long wire, and sprinkled over this a mixture of red lead and sulphur, found the negative and positive figures very prettily exhibited. At the moment the discharge was brought to the discharge, and before the electricity passed, a star appeared at each point of the wire, showing that one half of the wire was + and the other - at the same instant. At the moment of the discharge, a smoke arose from the red lead as if from the reduction of the metal, and the track between the two points of the wire or rather of the universal discharger which was inserted at the opening of the wire, was marked by six passages. Made the same experiment with the large conductor instead of the jar, found the negative and positive figures as in other case, but not above half the diameter. When the glass with coating on the underside was removed, and one without coating substituted, the figures were not produced in any perfection, and were particularly deficient around the negative pole. [[image of drawing]]
[[start page]] [[top margin]]216 Feby 22nd 1845 [[image - diagram with jar and conductors]] [[left margin - annotation for the diagram]] wire to the wall Connected the long insulated wire suspended around the room with the wire going to the wall, placed the two extremities of the insulated wire over the two insulated brass conductors, between which a jar was placed _ a series of sparks was then passed between the large conductor and the ball [[underline]] c [[/underline]], the [[interposed?]] jar was [[underline]] not charged [[/underline]], although a series of bright and dense sparks passed between the knob and the neighbouring conductor, the effect was the same whether the knob was presented to the conductor attached to the first or last end of the long wire. The effect was also apparently the same, whether the jar was held in the hand, or supported on its side on bees-wax. This result is in exact accordance with all my other experiments, and the conclusion that I have arrived at, is that the charge is progressive, a spark being sent in one direction and afterwards from the other conductor in the other._ 2nd that an induction precedes the plus wave, but this is not as evident, and it is only supported by theoretical considerations as well as the fact that the spark is as powerful when the jar is held in the hand, as when it is supported on bees wax_. Also it would appear from this experiment that the view expressed in page 213 of the spark passing back to a conductor, which returns to its natural state, is not correct, for if this [[end page]] [[start page]] [[top margin]]Feby 22nd 1845 217 were the case, why should a lateral spark charge the jar with free electricity._ To show that the jar is thus charged with the arrangement I have described on the last page, the jar was first touched, or rather brought near the conductor at the first end of the wire, and afterwards its knob was also placed near the other conductor, it being held in the hand during the time, in both cases it was found powerfully electrified + [[underlined]] plus[[/underlined]]. [[line across page]] [[image with annotation -walls- on the left margin]] The wire around the room was connected with one of the conductors, while the other conductor was presented to it at the distance of about half an inch, the conductor being held in the hand, at this distance the sparks did not pass at d. When however the two conductors were both connected with the wire, as shown in the figure, the sparks passed freely and were quite brilliant. The spark between the conductors. When the wire is placed over [[underline]]d[[/underline]], or not, presents very different appearance, in the one case it is a positive spark quite thin and of little quantity,- In the other case spark is broad, sometimes appears to exhibit prismatic colours, and has a flame of a reddish colour in the middle. [[bigger font]]Make this spark appear in a [[underlined]] vacuum. [[/underlined]] [[/bigger font]] [[end page]]
[[check mark]] 218 Feby 25th 1845 The spark from the wire was longer when the whole length around the room was added, showing that the lateral is greater with a less conductor, this however has probably its limits. Tuesday 25th [[line across page]] [[image of cylinder]]coated the part [[underlined]] a [[/underlined]] of the battery. I received from NY with sealing wax, or rather gum shelac, so as to prevent any dissepastion at the surface, but I found that it was impossible to give them a charge. The electrometer rose indeed, but very slowly, although the machine was in admirable order, [[word scratched out]] then fell down immediately after the turning ceased. A small charge was retained for some time, showing that the glass is a partial conductor, and that time is required to complete the discharge through the thickness of the glass. [[Line across page]] [[hand drawn image]] The experiments given before explain a phenomenon in reference to the jar. If the knob of the Leyden phial be placed in contact with the prime conductor of the machine, while it is insulation sparks will pass to a neighboring conductor [[underlined]] a [[/underlined]]but if the phial be connected with the ground, no sparks will pass at [[underlined]] a [[underlined]] If however the ball [[underlined]] b [[underlined]] of the jar be removed a little distance from the prime conductor, so that spark will pass between them, then sparks will pass [[underlined]] at a [[underlined]] although the insulation of the jar remains destroyed. In this experiment, the jar is charged on the inside plus, by the spark received into it, and also on the outside in the same manner, for an instant by induction, that is the lateral or natural electricity becomes free, and hence the spark which is much shorter than that from the machine. [[end page]] [[start page]] [[words circled]]Feby 25th 1845 [[words circled]] June 3rd 1845 219 Since the last date, my time has been so much occupied with teaching, that I have been able to do nothing in the way of experiment. To day I weighed a piece of lead wire, through which mercury had been passed in comparison with a piece through which the mercury had not passed, and found the increase of weight due to the saturation with mercury just 50 percent. Also stretched a piece of india rubber- along the outside of Nicholson's hydrometer, then brought the instrument to stand at the zero point in a vessel of water, then the point on the stern was noted where the water intersected it after the rubber had been released from the extending force, but I could see no difference in the position of the floating vessel. From this experiment , I infer that india rubber is not charged in bulk by extending it, or if charged the amount must be exceedingly small. [[words circled]] This has since been proved by exp ; under direction of coast [[?]] May 7th 18?? [[/words circled]] Found in looking over the Biblioteque de Geneve No 6, Jun 1836, a paper on the formation of liquid drops, by means of a small hole in the bottom of a thick glass vessel, found a great difference in the size of the drop by a change of temperature. The size of the drops was found by counting the number required to produce a given weight, or to fill a given vessel. The first method was the most expeditious. The size of the drop was influenced by the pressure of water in the vessel which caused the drop to be formed. The relative size of the drops of different liquids is in the ratio of the heights of the same liquids in capillary tubes. Why does oil spread on water?
220 June 5th [[vertical squiggle]] Capillarity Why does oil spread on water? If oil for oil, and water for water have a strange attraction for each other than oil has for water, we would suppose that the oil would remain without diffusion on a given spot of a surface of water, we know however that there is a great power of diffusion exerted, and may not this be due to the great attraction of the water for itself, which prevents it uniting with the oil, while at the same time the attraction of the oil for the water is greater than that of the oil for itself. If a film of oil of some thickness be poured on water, and then a wooden disc smeared with oil placed on the surface, would not the seperation be between oil and oil, and not between the oil and water, or in other words, would not the experiment indicate the result in accordance with the above supposition. Try. The fact that a film of oil may be diffused over a soap bubble is favourable to this supposition. [[image - hand-drawn pen sketch of a cup containing a liquid with another layer of liquid sitting separately on top of it]] Poured some olive oil on the surface of water in a tumbler, the oil was attracted upwards so as form the [[circled]] curve [[/circled]] of capillarity and also downwards, the greasing of the side of the tumble brought into play the attraction of the water for itself and the edges appeared rounded like the mercury in a glass vessel. [[image - hand drawn pen illustration of a cup containing a liquid with another layer of liquid sitting in a separate layer on top of it. A vertical tube has been inserted through both liquids.]] When a piece of glass or ivory was plunged into a tumbler of water, over which a film of oil was spread, the oil was bent down and formed as it were, a sheathing over all the ^ [[insertion]] ivory [[/insertion]] handle, showing the attraction of the wood for the oil was stronger than for the water. [[end page]] [[start page]] June 5th 1845 [[vertical squiggle]] Capillarity [[hand-drawn illustration of circle with a thin half circle underneath]] 221 Spread a thin film of oil over a surface of water in a tea saucer, then attempted to take off a part of the film with the finger, the end of an ivory knife tc, to back all attempts [[crossed out were??]] uneffectual in exposing the water, the rupture always took place between oil and oil, and not between oil and water. Made the same experiment with a disc of 2 inches and a half, put down on the film of oil so as to prevent the action of the closing up of the small spot of the surface of the water, which might never been produced when the finger on the end of the knife was employed, but the result was the same, the rupture was still between oil and oil, and not between oil and water. [[hand drawn illustration of a large cylinder, sun shape on top with letter 'a' in the middle]] A singular phenomenon is presented when a quantity of oil is poured on a tumbler mainly filled [[strikethrough]] with [[/strikethrough]] with water, the surface often exhibits a circular spot [[underlined]] (a) [[/underlined]]of water which is apparently elevated slightly above the oil, ad is perfectly circular, when it has been suffered to assume the conditions of equilibrium, the explanation of this to me just as pressure is not very clean. Also, explanation of the same kind is presented when some large drops of water are poured into a tumbler filled with oil some of the drops immediately fall to the bottom, while others remain adhering to the surfaces as in the sketch. [[hand drawn illustration of explanation, line with a round bubble beneath]] Make some experiments on this. The phenomenon exhibit in the experiment of pouring either on water, In not the cause of the fall of the scale [[circle]] pan [[/circle]] the formation of a [[??]] of the liquid on the surface of the perpendicular elevated water.
222 Capillarity Professor Gibbes informs me that an animal [[strikethrough]] called [[/strikethrough]] of the Limnea genus walks on the under surface of the surface of water. When the animal rises to the surface of the water, by climbing along a plant, and wishes to go [[strikethrough]] go [[/strikethrough]] from one plant to another, he crawls along the under side of the plane which forms the boundary of air and water. Professor Gibbes has also thought of the self registering thermometer. To show the insufficiency of the attraction of gravitation, let us suppose a single point on the sphere of water projecting outwards, it would require months to draw this in by gravitation according to the experiments of Cavendish. The action of the contractile force is shown in blowing a bubble of glass - When the bubble is heated, contraction takes place. For a remark on soap bubbles, see Bacon vol XIV p 65. If a small piece of sealing wax of the size of a midling sized shot say no 2 or 3, be dropped into a tube contain water at its lower end supported by capillarity, the [[strikethrough]] shot [[/strikethrough]] wax will not fall through the lower surface, the contractile force retains it. This experiment is the inverse or counterpart of that of the floating of a needle on water. When the fragment of wax is [[circled]] examined [[/circled]] it is seen to protrude from the under side of the drop increasing the curvature. The suspension of the small piece of enamel in the self registering thermometer is on the same principle. [[image: capillary tube with small amount of water and fragment of wax. Caption: see pages 1st of this book for an experiment bearing on this fact.]] [[end page]] [[start page]] Dec 26th 1845 223 Observation on the apparent motion of an observer when regarding fixedly a large moving object Since my experiments of last winter vacation, I have been engaged in college duties and in the study of mechanics, metaphysics &c. Last summer vacation I spent in visiting my friends and acquaintances at the north, this was the first vacation I have employed in this way for several years. On my way to Albany, I started with my family in a waggon to take the cars at New Brunswick, the horses were not used to travelling with each other, and when we got to Kingston one of them became restive, and we were obliged to send it back to Princeton. While we were waiting for the return of the horse, I walked [[line across page]] to the canal and watched the operation of elevating a large boat to an upper level. I was standing on the side of the lock,[[line across page]] two little girls looking down into the lock into which the boat was entering, when at a certain position of the boat, I felt the sensation of moving, or in other words the boat suddenly appeared to stop its motion, and I and the warf on which we stood appeared to move, this is a very common appearance, and would not have specially attracted my attention, had not the little girls at the same moment exclaimed [[short line drawn]]"we are moving", that we should each experience the same sensation at the same moment was a circumstance which excited my curiosity, and I immediately set about attempting to ascertain the cause. The first hypothesis that suggested itself to my mind appears to be the truth. We are from long experience accustomed to see the smaller spaces which occupy our attention on the surface of the earth in a state of motion, rather than the larger ones. Thus the car, the boat, the waggon, is in motion, while the road, the field, the sky, are at rest, hence when ever two bodies of very different
224 Dec 1845 Observation on appearance of motion sizes are in relative motion, there is a tendency in the mind to refer the motion to the smaller, and to consider the larger at rest. on this account,when the moon is seen through patches of scudding clouds, the latter appear at rest, and the former to be in rapid motion. To explain on this principle the phenomenon of the two little girls and myself observing the apparent motion of the warf at the same moment, I adopted the antecedent probability, that when the boat as it approached the part of the canal immediately opposite, where we were standing came so near as to occupy more than half the field of view, or in other words when it become larger than the part of the warf taken in by the field of view at that moment, the motion would be transferred from the boat to the warf.To test this idea, I turned my eye around so as to bring the field of view over the warf, and to occupy more than one half of its surface with unmovable space, the motion of the warf then ceased, and by turning myself around again, I was able to make the apparent motion again become perceptible. There was however something like persistance in the impression for the motion of the warf did not immediately cease, when the field of view was more than half occupied by it, but it appeared to continue for a short time. also when I turned myself so that the moving boat occupied more than half the field of view, the motion of the warf did not immediately commence. Make some experiments on this point. [[End page]] [[start page]] Dec 26th 1845 [[short squiggly line]] Capillarity 225 I was directed by Mr Hardley to the fact when on the steamboat going to albany of the bubbles on salt water being much more tenacious and the appearance of the surface on account of the agitation of the boat much more frothy than in fresh water under the same circumstances. Different liquids have different degrees of [[circled]] vicidity [[/circled]], as in the case of water and alcohol, the bubbles or beads of the latter are more persistant than those of the former, indeed the strength of the liquid, or the amount of alochol is judged of by the [[?]] in the article by the [[?]] it bears. Perhaps the lightness of the alcohol may have some influence on the result. Make experiments on these points. In one of the late nos of the Compt Rendus of the [[?]] academy, there is a notice in two lines of the transparency of the bubbles of mercury. Try this. Exp - Shook phial of four ounces half full of oil of anisseed, the bead remained. Exp 2 Shook four ounce phial of spirits of turpentine, bead almost instantaneously disappeared. [[underlined]] Exp 3 [[underlined]] Shook similar phial of sulphuric ether, beads almost instantaneously disappeared. Exp 4 - shook similar phial of common alcohol, beads almost instantaneously disappeared. Ex 5 same with similar phial of sulphuric, and beads remained. Exp 6 Phial sulphate of zinc, bubbles remained longer than those of water.
[[start page]] [[top margin]]226 Dec. 26th 1845 Capillarity[[/top margin]] Exp. 7. Phial of [[circled]]antic[[/circled]] acid, beads remained a second or two longer than those of water. Exp. 8 Phial of acetate of lead, bubbles persisted several minutes _ became very minute before disappearing. Exp 9. Phial of acetate of zinc, bubbles remaining but not quite as long as those of the acetate of lead. Perhaps the difference may have been due to the difference in the strength of the solution. Exp 10th. Compared a phial of pure water and one of salt and water, found the latter produced more persisting beads, the difference however was not much. Exp 11. Shook phial of mercury, but could not make beads. Of all the substances tried in these set of experiments, the oil of anisseed gave bubbles which remained the longest. By shaking the phial rather violently, the whole surface of the liquid was covered with froth of small bubbles, these were high at the edges, being drawn up by the capillary attraction of the side of the glass nearly half an inch. At first the whole surface was covered with small bubbles, [[indented to allow for figure on the left of the page]] and was constantly agitated by the breaking of the bubbles, sometimes into the air and sometimes into each other. The whole surface continued to be covered until by the bursting of a larger bubble, the equilibrium became disturbed and a vacant space [[strikeout]] formed in the middle, which expanded until a single [[end page]] [[start page]] [[top margin]]Dec 26th 1845 [[beneath this]]27[[/]] Capillarity 227[[/top margin]] row of beads remained at the circumference. The reason why the space thus enlarges outward appears to be that the bubbles are supported, and sustained on the out side, but not on the in, hence they break on the [[strikeout]]inner side of the ring. The bubbles remain longer on the side of the glass because they are supported and the liquid kept elevated by the capillarity of the glass. It appears from the foregoing experiments that the solution of a solid in a liquid tends to increase the tenacity of the latter, but in very different degrees according to the nature of the substance. [[underline]]Dec 27th[[/underline]] Made a mixture of alcohol of about one fourth water, found the frothings of the mixture greater than that of pure alcohol or common water. At the last meeting of the Phil society, I gave an account of the result of a series of experiments by Capt Stockton of the US Navy, on the bursting of guns with the wad not rammed home, and the converse. He finds that the tendancy to burst is not greater with the ball down, but part of the way. See his paper, which is to be published in the proceedings of the society. At the same meeting, an account of an experiment was given by Mr Justice of a needle in water drawn up to the surface by a magnet which then floated, although it had been surrounded with water, and was therefore presumed to be wet. I have repeated this experiment this morning, and find the result as described, the cause of the floating apparently is that the needle is not wet by sinking to the bottom. Polished steel does not become infilmed by being dropped into water. [[end page]]
[[start page]] [[top margin]]228 Dec 27th 1845[[/top margin]] Polished piece of steel with calcined magnesia, dipped it into water, it came out [[?enfilmed]]; _ dipped the same into alcohol, it now came out covered with the liquid. _ Dipped the same into spirits of turpentine, after having removed the alcohol, it was again unfilmed. Heated the steel so that it hissed when it was plunged into the water, but still the liquid did not adhere. That the steel has an attraction for the water, is shown by the fact that when the article was plunged into the water, the liquid was drawn up, as in the figures, [[indented to allow for small figure to the left]] but this attraction was less than that of the liquid for itself, as is proved by the steel's coming out of the liquid uncovered.[[/end indent]] Also when the steel was pushed into the water, a depression on each side was observed, as is shown in the figure. This [[indented to allow for small figure to the left]] effect is due to the attraction of the water for itself, being greater than that of the water for the steel. [[/end indent]] When a piece of mica was split, so as to exhibit a perfectly clean surface, and plunged into water, no adhesion was observed. When the same was plunged into alcohol, it came out infilmed. [[small text, right justified]]For facts in capillarity see Peschel's Physics p 54[[/end right justified]] The steel, after being placed for a few minutes in sulphuric acid, which slightly acted on its surface, was infilmed with water. [[end page]] [[start page]] [[top margin]]Dec 27th 1845 Faradays new condition of matter 229[[/top margin]] I received a note a few days ago from Dr Gray of Cambridge, informing me that Dr Faraday had found a connection between electricity and light. The account was from a notice of the discovery in an English paper from Sir James South and gave no details. I have since received a more extended account of the experiments from Professor Pierce, in an extract of a letter from a young gentleman who was present at the reading of Dr Faraday's papers. The experiment consist in general of passing a polarized ray through a tube containing a liquid or solid, and then bring near the tube, a magnet of great power, the polarized beam rotates around its axis, so that if an [[circled]]analizer[[/circled]] be so placed at the other end of the plate, that the light is shut off. When the magnet is approached to the side of the tube, the light became visible on account of the depolarization of the ray. The same effect is also produced by using a helix surrounding the tube. Different substances exhibit the rotatory tendancy of the beam in different degrees, and that which exhibits it most is the glass made by Mr Faraday and described in the Phil Transactions. I have long sought some action of this kind, and have planned a number of experiments on the subject, which like many other plans, I have not realized. [[line drawn across width of page]] [[dashed line drawn from inner binding of the book, appears to indicate note on the previous page re: Perschel's Physics]] The same force which elevates a cylinder of water in a fine tube, will prevent it from evaporating. Water in capillary tubes does not evaporate when [[circled]]hung[[/circled]] in the sun for a long time [[circled]]?[[/circled]] Experiments on this point _ [[end page]]
[[start page]] [[top margin]]220 Dec 27th 1845[[/top margin]] Made an attempt to repeat the experiment of DF for this purpose made a cylindrical helix of about 180 feet of covered bell wire. In the axis of this was placed a tube containing spirits of turpentine and the whole apparatus supported in the polarizing apparatus of Mr Nuremberg. When the polarized beam was passed through, and observed by an analizer of carbonate of lime, the two complimentary images were very beautifully exhibited, and a slight circular motion of the tube was sufficient to indicate a change in the beam by the change of color. The apparatus being thus arranged, a current of galvanism [[?]] from 5 of Daniel's battery cups was passed through the wire of the helix, but no effect, or if any, a very slight one, was perceptible. [[lower half of the page is empty]] [[end page]] [[start page]] [[top margin]]Dec 29th Monday 1845 Expansion of air by an electrical discharge_ 231[[/top margin]] [[indented to allow for small figure to the left]] To acertain whether the sudden expansion of the air in the electrical air thermometer of Rinersly is due to the heat of the electric spark, or to a repulsive energy imparted to the air, I suspended a small thermometer within the tube and noted the effect. [[/end indent]] At the third discharge, the thermometer was broken to pieces. I could not perceive from the two preceding discharges that the mercury had risen in the tube, _ When in a previous experiment, the thermometer being in the tube, a series of [[underline]]sparks[[/underline]] were passed through. The thermometer appeared to rise a little, but I am not sure that this effect was not due to changing the position of the instrument from the colder window to a position on the platform of the large electrical machine. When a discharge from the same jar, which broke the thermometer, was passed through the tube with water at the bottom, the liquid was thrown up at each discharge an inch and a half in the small tube, and immediately subsided again. That the expansion in this experiment was not due to the heat of the spark, would appear from the following observations. I held the same apparatus over the flame of a candle so as to expand the air to the same degree as before or in other words, until the water was forced up the small tube to the same height, and then suffered the water to descend by the cooling of the air. in this case, instead of falling instantaneously, or almost too soon to distinctly observe its altitude, it occupied about 10 minutes in making the descent. I think this observation is conclusive in establishing the fact that the expansion of the air is not due to the heat generated. [[end page]]
[[start page]] [[top margin]] 232 Dec 30th 1845 Mr Faradays New Condition of Matter[[/top margin]] Sam was engaged all day yesterday in making me a coil for the purpose repeating Mr Faraday's experiment. He finished it a few minutes ago. It was formed by winding 800 feet of, or about that quantity, of covered bell wire over a thin gun barrel and leaving the two ends projecting for connection with the battery. Into this helix, first a tube of oil of turpentine was placed with a Nichols prism on the end, and next a window, and an analysing prism of carbonate of lime at the other end. A current was then passed through the wire from 20 cups of a Daniell Battery, arranged as two sets, so as to give more quantity with this. I could not perceive any effect. [[strikeout]]The[[/strikeout]] Next the gun barrel, which had been withdrawn previous to the former experiment, was replaced, but still no effect was perceived with the turpentine. Again the tube of turpentine was removed, and its place supplied inside of the gun barrel with a tube of water, with the analyzing prism before used. No effect was again produced. Next with the glass tube ^ [[of water]] and the same arrangement as before, with the exception of the substitution of a tourmaline analyzer, the experiment was repeated, and now the effect anticipated was very striking. At the instant of transmitting the current, the field became lighter, and at interrupting the same, the reverse change [[end page]] [[start page]] [[top margin]] Dec 30th 1845 Faraday's New condition of matter 233[[/top margin]] was produced. The effect appeared the most striking at the moment of opening the current, although it was very brilliant at both the closing and opening. With half the number of cups, the effect was much less distinct. To exhibit the phenomenon in its most striking character, a powerful apparatus is required, or a very long helix. The experiment also succeeded nearly as well, if not quite so, when the gun barrel was removed. I found that the tourmal gave the most striking effect when it was so turned as not to cut off all the light. Tried the same experiment on a piece of glass cylinder, the result was not very satisfactory, although there was an indication of the change of polarization. [[the remainder of the page is blank]] [[end page]]
[[top margin]] 234 Dec 30th 1845 Motion of mercury between the poles of a galvanic apparatus[[/top margin]] Made some hap hazzard experiments on the motion of mercury between the poles of a galvanic battery. This phenomenon first studied by Sir G Herschell, has attracted my attention for several years. When a quantity of mercury was placed in a tea saucer and the plus pole plunged into the mercury, while the negative pole was placed at a small distance, rapid currents were [[indented to allow figure to left]] produced as shown in sketch When the negative pole was held over the middle of the disc of mercury, motions took place on every side outward along the surface of the mercury, and inward on the surface of the water, [[/end indent]] and this was the case what ever was the position of the + pole. The effect was best shown when the metal was covered with a stratum of pure water or water but slightly acidulated. Tried the effect of the apparent repulsion with two platinum poles, but without perceiving the same action. Also placed in the bottom of the saucer a round disc of tin foil, and placed the plus pole on the middle of this, and the negative pole on one side, and also immediately over the surface, but the motion of the water did not take place as in the case of the mercury. [[end page]] [[start page]] [[top margin]]Feby 21st 1846 Lifting power of the large magnet constructed in 1833 [[check mark]] 235[[/top margin]] [[indented to allow for figure on left]] Tried to day the lifting power of the large magnet belong to the apparatus of the college, constructed by my self in 1833. This lifted at the time of its first construction 3600 lbs with the large battery of 88 true plates arranged as 4 plates, but I had supposed that the insulation had been injured by some accident in moving the apparatus. In this however I was mistaken, for it was found on trial to day that it was still capable of sustaining 3500lbs. The estimation was roughly made, but the sum stated is within the truth, eight men stood on a plank placed across the seale pan, and three men pressed by their weight, on the end of the iron lever. The magnet in this experiment was excited by two parts of the large plate battery arranged as one pair. The acid was very strong and formed at least 1/10th of the liquid. When the poles of the battery were disconnected, or in other words, the galvanic circuit broken, the magnet sustained for a few minutes upwards of a thousand powers. The same retaining power supports the keeper from year to year, and between two and three hundred pounds ^[[insert]] pressure [[/insert]] are required to pull off the iron after it has remained in contact for a 12 month. I have never published an account of this magnet, although it is the most powerful yet made. This magnet exhibits the curious phenomenon of persistence in polarization. If it be magnetized so that say the right leg is a north pole, and afterwards the current be changed so as to make the same ^[[insert]] leg [[/insert]][[strikeout]]pole[[/strikeout]] a south pole, after the current is stopped, the first polarity returns, although the action may have been very intense!
[[top margin]] 236 March 4th 1846[[/top margin]] I find it stated in the 93 no of the Living Age (Littelle's) that Mr Hurst of England has found that precipitation and crystalizature are affected by magnetism. If according to the account a glass trough containing a substance in the process of depositing a [[circled]]precipitate[[/circled]] be placed between the poles of a magnet, the precipitated matter will arange itself in the form of magnetic lines. Also a substance in a state of crystalizing placed in the same circumstances, will exhibit the same phenomenon. [[small figure of U-shaped magnet suspended beneath a rectangular plate]] To test the last mentioned fact, a horse shoe magnet of considerable power was placed perpendicularly, and across its poles a plate of mica was laid, around [[strikeout]]this[[/strikeout]] which a border of bees wax was [[strikeout]]laid[[/strikeout]] raised, so as to form a cup to contain a solution of sulphate of copper. [[strikeout]]July[[/strikeout]]March 4th Examined the result of the experiment which I instituted on the 4th, as to the affection of the crystalization of the sulphate of copper under the influence of a magnet, but could perceive no particular result. the crystals of sulphate of copper were beautifully formed, but they observed no law as to arrangement in reference to the magnetic curves. ___ I do not think the fact stated by Mr Hurst is correct, although it ought not to be denied on the result of a single attempt. Pour honey from a spoon into a dish, a thread 3 feet long may be formed, as thin as a fibre of silk. [[end page]] [[start page]] [[top margin]] April 10th 1846 Capillarity 237[[/top margin]] In conversation with Professor Barley, he informed me that the spheroidal condition may be given to ether by pouring a few drops on a surface of heated water. ____ The idea in the same connection also occurred to me of the more perfect explanation of the spreading of oil on water. ___ The ^[[general]] cause of the spreading as I have before shown, is the fact of the attraction of oil for oil being less than that of oil for water, while at the same time, the attraction of water for oil is [[strikeout]]greater[[/strikeout]] ^[[less]] than that of water for water. Now suppose the attraction of oil for oil was [[indent to allow for figure on left]] greater [[strikeout]]less[[/strikeout]] than that of oil for water, then we should have a drop of oil on the surface of the water assuming the form of that in the upper figure, but if the attraction of the oil for the water was greater than that [[/end indent]] of the oil for itself, then the drop in the first instance would assume the form given in figure 2nd, the curvature of the outer surface would be such as to cause the drop to expand on all sides and flatten out. the next drop thrown on would be removed from the sphere of the attraction of the attraction of the water, and would assume a lenticular form, like that represented in the figure, the weight of the oil when it is thrown on [[indent to allow for figure on left]] the surface of the water depresses it, so that the drop of oil is very nearly within the surface of the water, the elevation of the middle being only the difference [[/end indent]] of the specific gravities. [[indented to far right side of the page]]For a paper on capillarity by Mr Ivory, see Phil Transactions, vol for about 1816. [[end page]]
[[top margin]] 238 April 10th 1846[[/top margin]] A few days ago I was reminded of an experiment in electricity which had previously been mentioned to me by Professor Loomis, namely a metallic wire is placed in the axis of a glass tube, and ^[[the point]] so drawn in it will not act to draw off the discharge from a conductor after the manner of an ordinary point. The explanation I am enabled to give [[indent to allow figure to left]] of the phenomenon is as follows. The several parts of the discharge repel each other, and the lines of transfer will be as shown in the figure. the induction will take place through the tube, and the greater pass to the out side which will thus become charged in the form of a ring around the tube opposite the point, and the redundant electricity of this ring repels the electricity of the conductor, as much as the point attracts it. This may be verified in several ways. May 1st 1846 Observed in paste which had grown cold bubbles consisting of a thin film of considerable tenacity. The contractile force of their formation was exhibited by a concave impression in the surface of the paste. I have also observed [[indent to allow for figure to left]] that by placing the mouth of a tobacco pipe in melted cement of bees_wax and rosin, a thin [[circled] plate[[/circled]] can be obtained. Since the last date (April 10th), I have repeated for my class the experiment of Mr Faraday on the circular polarization of water, by means of electricity (see page ), and I found the truest of the plane the same as he has stated, namely in the direction of the current. [[end page]] [[start page]] [[top margin]]239[[/top margin]] according to the theory of Ampre, the currents in the inside of a gun barrel ought to be different from those on the outside in direction, and hence the currents within a gun barrel should neutralize those without with a certain thickness of the metal. This is in accordance with the results obtained by Dr. Faraday. This not surprising after a little reflection, that the rotatory action of the current should be greater within a gun barrel than without, since before the thickness sufficient to produce neutralization is all aimed ^[[on the outside]] the action of the magnetism developed will more than counteract that developed on the inside. ___ I found the effect greater when the 24 cups of the battery were arranged as a single series, than when the same number were arranged as a double series of 12 cups. May 6. The idea that the universe is a machine moving by its own inherent energies, is contrary to strict deductions from analogy. A machine is an instrument devised by an intelligent agent for the application of a power to the production of some effect or design. The world, or I should say the universe ^[[if it be a machine]] from this analogy must be the production of an intelligent agent for the application of a power, but the power is never in the machine itself, but is applied to it. A machine cannot generate power, it merely applies it, hence the universe, if a machine, must move with power derived [[underline]] ab extra[[/underline]]! If the universe be not such a machine as that constructed by human intelligence, then all analogy in reference to the mechanical arrangement and motion of creation must cease, and that which is offered as an Atheistical hypothesis for the existence of the universe has no philosophical basis.
240 Oct 3d 1846 Experiment on the cause of a ball being suspended on a jet [[three figures are sketched in the left margin, spaced down the length to display different experimental set ups]] Experimented this afternoon on the cause of the suspension of a ball on a small stream of water. The phenomenon is a very surprising one, and is not explained in the ordinary books. The arrangement to produce the effect was as follows. A bell glass was inverted, a glass tube passing through a cork inserted into the orifice. The tube being previously bent at the lower part, and drawn out so as to form a jet pipe, which gave a stream of about one tenth of an inch in diameter, and which spouts upwards about 2 feet and a half. The ball which answered best with the force and size of stream was one of maple wood of about one inch, or perhaps a little more in diameter. With a large ball, the effect was not as permanent, the ball falling off. With the smaller ball, the effect was produced for ten minutes at a time, the ball during the whole time continuing an oscillatory motion. That the effect is not due to an ascending current of air, as some have supposed, is shown by placing a piece of paper near the side of the jet, so as to intercept the current, the ball still remains suspended. [[image on left margin]] Neither is the effect due to a rolling of the ball on the side of the jet, as at [[underline]]a[[/underline]], for in these experiments the jet was so small that the powerful part of the liquid passed up on one side, when the jet struck the ball on one side, [[figure]] and consequently the rolling would tend to throw it farther off the jet. That a rolling tendancy does exist in the ball when the jet strikes one side, is shown by the following experiment. A glass cylinder was placed on two parallel wires, [[underline]] a b c d[[/underline]], a little inclined [[image in left margin]] so that the cylinder might roll down and touch at its side, the ascending stream in this case, the cylinder was made to roll back by the impulse of the water on its side, descending again by the force of gravity. [[end page]] [[start page]] Oct 3d 1846 Ball on jet 241 [[left margin]]four simple figures drawn down the length of the left margin[[/left margin]] it would again move back, and so on several times in succession, or as long as the stream was kept up. When however the cylinder was pushed a little into the stream, the water was observed to curve around it, and to be thrown off in a series of tangents (see figure), the cylinder did not then roll. The final conclusion from all the experiments, is that the effect is due to the tendancy of the water to move in a straight line. As it is caused to move in a curved line, the centrifugal force at [[underline]]a[[/underline]] draws the ball in the direction of the arrow, and constantly tends to bring the stream under the lower point of the ball. [[image]] When a string of fine silk thread was attached to the ball, and drawn, so that the ball not directly above the stream, the water was thrown directly over on to the hand which drew the string. [[image] A piece of cork in the form of a cube was not retained for an instant on the stream, in this case the force of the sides did not permit the centrifugal force to be developed. [[image] A ball with a larger pin through it was retained, the pin was observed oscillate through an arch of 30 or 35 degrees. Hence a rotative motion does not appear necessary to the ^[[success of]] the experiment. The ball however in some cases is observed to rotate.
242 Oct 27th 1846 Ball on jet of air [[image of figure ]] Placed a wooden ball of about 1/2 an inch in diameter over the orifice of a tube, though which a stream of air was blown from the lungs. The ball was supported as if by a jet of water. The same effect is produced by placing a ball over a jet of steam. If the ball is connected with a string, it may be drawn to one side, and will again return to the axis of the stream. Placed on the same stream of air a ball with irregular surfaces, or I should say, with different faces, this was immediately thrown off. For an account of some observations on the support of a ball in a stream of steam see Phil. Mag vol p . See [[circled]] Tighlmans [[/circled]] letter to me 1846. In a conversation with Mr Tighlaman, on the subject of the suspension of the ball in the case of steam, it was suggested that the effect was produced by a vacuum formed immediately above the ball. When the ball is on one side [[image of figure on left]]of the axis of the stream, then the vacuum will also be on the side, but inclining inward so as to upset the ball toward the axis. That such a vacuum should exist, will be evident from the fact that the effect is produced in the case of a body moving in a liquid, the negative pressure behind and the positive before. Mr Tighlman suggested to me a form of the electrical machine which might give more intensity of electricity. It consists in a long conductor [[image of figure on left]] placed with its middle opposite the edge of a glass plate machine. The middle of the conductor having the greater capacity, a longer spark can be drawn from each end. [[end page]] [[start page]] Nov 10th 1846 Elasticity of metal Observation on Millone's heat of the moon 243 The general impression given in books on natural philosophy, is that matter is perfectly elastic within certain limits, and that however often you bend a spring, within this limit it will always return to its normal state, the workmen of Philadelphia however are of a different opinion. They think that every vibration produces a permanent change, and that the spring never returns from the sightest bend to its first form. Some experiments presented to the British association would seem to prove the same, and on reflection it does not seem improbable that some of the particles or atoms at each vibration may undergo a change in position, though the greater majority retain the same relative position. It is said that a spring of given dimentions can only make a definite no of vibrations before breaking, the number will of course be inversely as the or. of amplitude. Melloni has lately obtained by means of the thermopile, indications of heat in the moon, the rays were concentrated by a large [[circled]] pologonial [[/circled]] lens, the pile being placed in the [[strikeout]] centre [[/strikeout] focus. It may be objected to the results of this experiment, that the black heat which would be the true radiant heat of the moon, is impermeable to glass, and therefore could not be shown by the thermopile in the focus, the heat observed by Melloni was due to the reflection from the sun, and was no more the proper heat of the moon, than is the light the heat of the moon which we know is the reflection from the sun. I have no doubt but a polished piece of ice would reflect heat. Let the ice be placed as [[image of figure on left]] at [[underline]]a[[/underline]], a lamp at [[underline]]b[[/underline]], a screen at [[underline]]d[[/underline]], a thermopile at [[underline]]c[[/underline]]. First let the effect of the ice alone on the pile be noted. Then note the effect of the lighted candle, the direct effect being cut off by the screen. Try the exp.
[[checkmark]] 244 Nov 10. 1847 [[circled]] Becquerel [[/circled]] has shown Electrical Magazine that every discharge of electricity of what ever kind, is attached with a decomposition, if this be the case, every flash in the heavens must produce a current in the earth, which decomposes the material of the soil, and may thus affect the fertilizing properties. This is the result which would at first sight be produced, but on ^[[further]] reflection, I am not sure that this ^[[action]] will produce an appreciable [[strikeout]]effect[[/strikeout]]. The decomposition will be apparent merely at the two ends of the line thus _ [[figure spanning the page width]] To acertain whether the electrical spark produces heat in its passage through air a vaccuum, cement a piece of rock salt ^[[in the side of a glass tube,]] and on the out side of this, place the end [[underline]]a[[/underline]] of a thermo electrical apparatus. This experiment would settle the question of the action exhibited in the experiment with [[circled]]?Renneralics[[/circled]] air thermometer. [[line across page width]] Dec 10th, The discharge of a spark of electricity along a wire, is as I have before shown, progressive, and produces a great repulsive force in every direction, and particularly in the line of direction. [[indent to allow figure on the left]] Let [[underline]]a b[[/underline]] be a wire through which a charge is passing, the parts become self repellent at the place [[underline]]e[[/underline]], where the charge is, and this repulsion will tend to separate the rod in the direction of its length, one part tending to go up, the other down. The tendency to separation in these directions will be the same, whether the electricity is passing up or down the rod. [[end page]] [[start page]] [[top margin]]Nov 10. 1847 245 [[checkmark]][[/top margin]] [[indent to allow figure on left]] This consideration (I allude to that of the last paragraph), serves to explain a fact noticed during a severe thunder storm [[/end indent]], which took place last summer in Baltimore; in two or three places in the streets, the electricity fell upon the pavement and burst upwards, the stones and earth making a piramidal hole represented in fig 1, or better in figure 2. According to the foregoing principle, at the moment the electricity was entering the surface of the earth, all the objects through which it was passing were rendered lightly self repellent, and the stones were burst upwards in the form of a pyramid, because this would be the [[circled]][[solid?]][[/circled]] of least resistance. The same effect would be produced wether the electricity ascended or decended. The effect could not be due to the inertia of the electricity, for even had it inertia, the great velocity with which it moves would like the shot through a door a jar prevent it producing motion. The same action explains the fact which I have noticed in my old book (vol 2), of the piramidal hole which I have found in several cases of electricity passing through walls, examples George [[?Madeaus]] house on the flats, __ Barn on Rocky Hill, and at Mr Philips. [[remainder of page is blank]] [[end page]]
246 March 25th 1847 It is mentioned by count Rumford in the Journal of the Royal Institution, that the Introduction of balls of fine clay into a coal fire increases the heat, though the clay cannot enter into combustion and thus increase the heat. The idea at first struck me as ridiculous, but on reflection, I found that there was a clear physical analogy to support the probability of the truth of the fact, namely the increase of light which is produced when a solid substance is introduced into the feebly luminous flame of a spent lamp. To test conclusively the truth of the proposition, I put the thermo electrical apparatus in order and deflected the needle of the galvanometer by the heat of a spent lamp, to the amount of 15 degrees, the end of a [[indented for figure]] platinum wire of about six [[/end indent]] inches in length was then coiled into the form of a spiral and plunged into the flame of the lamp, the luminosity was of course considerably increased, while at the same time, the needle of the galvonometer moved from 15 to 27 degrees. The truth of the proposition is therefore conclusively proved by this experiment. But was is the cause of the phenomenon? is it due to the fact of the increase of the combination of the oxygen and hydrogen by the action of the platinum on the principle of the action of the flameless lamp, or is it the result of te conversion of heat of less radiating power into heat of greater. for a notice of Davy's new views of flame, see Bland, Vol 2, page 126 1817. The heat of flame may be diminished by in increasing the light. [[end page]] [[start page]] [[top margin]]March 26th 1847 247[[/top margin]] [[indented for small figure]] Placed a spiral of platinum wire [[/end indent]] in the lower part of the flame, found the light much less intense than in the upper part, also apparently the reduced heat. The glalvonometer without the platina stood at 19 degrees, with the platina in the upper part of the flame, it stood at about 25, with the platina in the lower part, a little less elevated. This experiment must be repeated. I could not manage being alone to hold the wire in the flame and note the degrees of the galvanometer. When a thin plate of mica, 3/4 of an inch in breadth, was held in the flame, the needle immediately passed from 15 degrees to nearly 30 degrees, the mica exhibited a very beautiful appearance such as I never before noticed. [[indent for figure on left]] It became white hot along the line of section of the outside of the flame and the mica while it remained dark in [[/end indent]] the middle. Showing in a vertical section the hollowness of flame. It would appear from the experiments of to day that the increased amount of radiation is due to the greater rapidity of the combination of the elements of the flame and the oxygen of the air, though the question is by no means settled. I need other substances. Flat plate of platinum foil 1/2 inch wide, effect great, needle of galvanometer passed from 11 to 30 degrees. __ hexcarbonal of lime, effect same. Also piece of glass, not all of the same intensity. Tried sulfate of lime, effect not as great as with platinum, still an increase of temperature was indicated. [[line across width of page]] * This experiment shows the parts of the flame most intensely heated very distinctly and gives us a new analysis of the flame relative to its temperature in different parts. [[end page]]
[[start page]] [[top margin]] 248 March 27th 1847 Flame _ Coloured circles around a candle _[[/top margin]] Davy suggests that the greatest intensity of heat possible may be produced by the combination of the effect of the voltaic arc and the jet of the compound blow pipe. This would merely produce a greater quantity of heat without increasing the intensity. Dr [[circled]]?[[/circled]] says the light of a flame may be increased while its heat is diminished. I was very much struck last night in going to bed to observe the candle in my hand surrounded with a series of perfectly distinct coloured circles, the perfect representation of Newtons rings. My eyes were slightly inflamed, and particularly the one with which the coloured rings were most distinctly seen. The inner [[strikeout]]?[[/strikeout]] more distinctly exhibited ring was about 4 inches in diameter, the candle being about 15 inches from the eye. The order of colour was yellow, red, blue, yellow, red, blue, etc. The diameter of the rings increased as the candle was removed from the eye. The plane of the rings was perpendicular to the line joining the eye and the candle, and continued to be so when the candle was moved. I have often seen colours around the candle, when I have got up from bed, in the night before working, my eye had never so distinctly seen the rings, been exhibited as in the present occasion. The effect is probably due to a film of [[circled]]mucus[[/circled]] spread over the surface of the eye, and may perhaps be initiated by dipping the finger into a solution of sugar and applying this to the eye. The order of sucession is that of the transmitted light of Newtons rings. [[end page]] [[start page]] [[top margin]]March 29th 1847 Flame 249[[/top margin]] Introduce into the lower part of a flame a piece of [[a separate piece of paper appears to be placed on top of the book page, obscuring rest of the writing therein.]] [[on the loose sheet of paper]] Count Rumford in a paper in one of the numbers of the Journal of the Royal Institution, 1st series, states as a fact, apparently from his own observation, that solid incombustible matter, shuch as balls of fine clay mingled with stone coal,increases the heat. We know that the radiation of light is increased by the introduction of solid matter into flame, and it is not therefore impossible that the same effect may be produced in reference to heat, but why such a result should be exhibited, I do not clearly see, either on the principles of radiation of [[strikeout]]a[[/strikeout]] material atoms, or the undulations of a system of material atoms. The experiment for settling the question is easily made with the thermoelectric apparatus. Introduce into the flame of the alcohol lamp a wire of platinum, note the effect. If the result be an increase of temperature, to what is the effect attributable? May it not be refered to an action of surface like that which produces the combination of oxygen and hydrogen. If this be the [[end of loose sheet of paper]] [[end of page]]
case, the quantity of alcohol burned in a given time should be increased by the insertion of the wire, and the increased heat would then be referable to an increased intensity or rapidity of combinations of the combustible elements, and the oxygen of the atmosphere. That the explanation I have suggested is the true one, would seem to be indicated by the fact that platinum wire without flame, [[strikeout]] increases the [[/strikeout]] produces the combination of the combustible and supporter in the experiment of the flameless lamp. The fact of the increase of combustion may be settled by burning two lamps of the same size, one with a coil of platinum surrounding the wick, and the other without, care being taken to eliminate all other causes of difference of action. The elimination of alcohol should be determined by weighing after a given time has elapsed. The exp could be better made with the same lamp, the platinum coil [[strikeout]] can [[/strikeout]] being carefully placed in the flame or rather around [[end of page]] [[start of page]] it without disturbing the wick. By separated experiments in this way, the fact of the increse of combustion or otherwise could be settled. The investigation appears to be one which might be interesting - In a conversation with Prof. Bache a few days ago, the questions was proposed by him, and answered by himself in the negative, can any amount of heat from boiling water be so condensed as to produce the heat of redness. The explanation of this phenomenon (taking it for granted that the effect cannot be produced), probably rests on the assumption in the theory of undulations that heat of different intensity consists of waves of different lengths, and this being the case, we should no more expect that the addition of black heat to black heat would produce red heat, than that the addition of [[strikeout]] re [[/strikeout]] blue light to blue light would produce red light. It may be possible that the introduction of the solid matter into the flame mentioned in the former experiment, changes the length of the vibration, instead of increasing the velocity of combination. Indeed an increase of velocity would affect the length of vibration. [[end page]]
That the length of vibration is [[?]], granting the truth of the theory, is shown by the fact that the intensity of light is increased by the introduction of the solid body. Persuing this train of reflection, I may ask is not [[strikeout]] the kind of [[/strikeout]] light changed in its character by passing through a transparent medium, and may not the results obtained by Sir David Brewster in his analysis of the spectrum, have been produced in this way. Connected with this subject is that of the difference observed in the chemical ray of the same colour derived from the prism, and from some colored medium. [[vertical wording lower right corner]] Speculations on Light and heat
248 March 27th 1847 [[short squiggly line]] Flame-coloured circles around a candle Davy suggests that the greatest intensity of heat possible may be produced by combination of the effect of the voltair arc and the jet of the compound blow pipe- this would merely produce a greater quantity of heat without increasing the intensity. Dr. [[?]] says the light of a flame may be increased while its heat is diminished. I was very much struck last night in going to bed to observe the candle in my hand surrounded with a series of perfectly distinct coloured circles, the perfect representation of Newtons rings. My eyes were slightly inflamed, and particularly the one with which the coulored rings were most distinctly seen. The inner more distinctly exhibited ring was about 4 inches in diameter,the candle being about 15 inches from the eye. The order of colour was yellow, red, blue, yellow, red blue, c. The diameter of the rings increased as the candle was removed from the eye. The flame of the rings was perpendicular to the line joining the eye and the candle and continued to be so when the candle was moved. I have often seen colours around the candle, when I have got up from bed, in the night before washing, my eye but [[?]] so distinctly have the rings been exhibited as in the present occasion. The effect is probably due to a film of [[word circled]] mucus [[word circled]] spread over the surface of the eye, and may perhaps be irritated by dipping the finger into a solution of sugar and applying this to the eye. The order of succession is that of the transmitted light of Newtons [[?]]. [[end page]] [[start page]] March 29th 1847 [[short squiggly line]] Flame 249 Introduced into the lower part of a flame, a piece of mica in the form of a slip of about a tenth of an inch in width, this became heated to whiteness, but when a piece of fine platinum wire was held in the same flame above the mica which was placed edgewise so as not to interupt the assailing flame, the heat of the wire was less than when the slip of mica was withdrawn. This experiment was repeated a sufficient number of times to convince me of the truth of the fact. The flame became shorter, when the mica was introduced, evidently showing from [[?]] the results that the effect of the mica was to cool the flame, and this was probably due to the increase of radiation. The principal action of the solid introduced into a flame is to absorb the heat of the luminous gas which is a bad radiation, and [[strikeout]] then radiate of freely into space, the process is therefore a cooling one to the flame, while it heats surrounding bodies. I am informed within a few days that an amount has been going the rounds of the newspapers of a method of saving fuel, by mixing clay with the coal. This effect would be produced by the solid radiating into space apart of the heat which would find it, way into the chimney. Flame according to Count Rumford, if I recollect aright, is a bad conductor of heat, and now for the first time in many years, a fact arises in my mind which was shown me by a gentleman in Albany, namely, when a stove is burning briskly, if the damper be shut, the pipe around the valve will become red hot, in this case the heated air is made to impinge against the side of the tube, and thus to impart the heat which would otherwise pass up the chimney. make experiments on the heat of different flames.
250 March 30th 1847 { Flame Transparency of according to the view I have taken of the cause of the phenomenon of the increased radiation of flame, by the introduction of a solid body, balls of clay introduced into the fire would not increase the rapidity with which water would be boiled , but only the quantity of heat radiated into the room heated by coal. The quantity of heat thrown on a dutch oven would be increased so that the roasting of the meat would be facilitated, while the boiling process going on over the fire would be retarded. Count Rumfour to prove that flame is transparent, held a candle between his eye and the sun, and thus eliminated the case which renders the flame opaque, namely the comparatively greater illumination of the flame than the body you attempt to view through it. A much simpler and better method is to hold the flame in the cone of diverging rays of light, thrown on a screen in a dark room, through a hole in the window shutter and a lens. In Flanders and in several parts of Germany and particularly in the [[words circled]] Duchies of Tuliers [[words circled]] and Bergen, where coals are used as fuel,the coals are always prepared before they are used by pounding them to a powder, and mixing them up with an equal weight of clay, and a sufficient quantity of water, to form the whole into a mass which is kneaded together and formed into cakes; which are afterwards well dried and kept in a dry place for use. And it has been formed by long experience, that the expense attending the preparation is amply paid by the improvement of the fuel. The coal, thus mixed with clay, not only burn longer, but give much more heat than when they are burned in the crude state. [[underlined]] Count Rumford[[underlined]] [[end page]] [[start page]] 251 making experiments on the invisible heat of a lamp
252 [[blank page]] [[end page]] [[start page]] September 16th 1847 [[short squiggly line]] Heat of the moon & heat reflected from ice [[short squiggly line]] 253 Melloni with a large convex lens has been able to exhibit the effects of heat from the moon by means of the thermo electrical apparatus, in his account of the experiment in the Compt Rendus for 1846. The results of this experiment does not appear to me perfectly satisfactory, the heat obtained in the experiment was not that of the moon, but the reflected heat of high intensity, which accompanies the light of the sun in its reflection from the surface of the moon. The object of the inquiry is the proper heat of the moon, and is analagous to the question of the self luminosity of the moon. To determine whether the temperature of the moon is greater than that of the surrounding celestial space, we must observe with the most delicate instrument the dark part of the moon, and even in case an indication of temperature were obtained, we could not be certain that it was not in part at least from the sun here reflected over from the earth and again from the moon. That the moon may be covered with ice at the temperature of celestial space, and still reflect the heat of the sun, is evident from the following experiment, which I devised nearly as quite a year ago, but which I made only to day with the assistance of Dr. Schenck. A piece of solid ice was smoothed on one surface, so as to form a plane mirror. [[image of a drawing]] On this, a beam of light from the sun was shown, so that it might be reflected into the end of a thermo pile. The temperature of the ice without the reflection was indicated by the needle and noted. The beam of light from the sun was then thrown on, and the temperature again noted. The galvanometer indicated a very considerable increase of temperature.
254 Sept 16. 1847 Showing that ice is an reflector of heat as with as of light. If therefore the moon were cooled down below the freezing point, it would still reflect the heat of the sun, and the thermo electrical apparatus exposed to the light of the full moon, would exhibit an elevation of temperature over that of the surrounding space. The moon from analogy and the appearance of its surface is in my opinion a cooled body. Smaller than the earth and plunged in the same medium or space the temperature of which is much below that of freezing,the moon should be colder than the earth. The kind of heat reflected from the moon is thus called white heat, and approximates light in its properties. We may suppose it to differ from black heat or that given off from no luminous bodies, in the length or intensity of the vibrations of the ethereal medium, on which the phenomenon of heat are supposed to depend. In the foregoing experiment, the heat reflected from the ice was that from the sun. It would be an interesting inquiry whether black heat can be reflected from ice. The [[Hernco?]] electrical telescope is susceptible of great improvement, and of of great extension. The mirrors do not require the same degree of perfection of form as in the case of the light telescope because the rays are not converged to a point, but to a surface of some extent, namely the surface of the end of the pile. [[end page]] [[start page]] Oct 18th 1847 255 Received to day a letter from A S Williams, teacher Orange Co. N. J., an account of the windows of a house broken by a powerful discharge of lightning, which must have passed at a distance, for no signes of splintering or other effects, to show the passage of the discharge along the building, were observed, The roofs of the dormitories at the University of Virginia are covered with metal. Dr. Patterson informs me that they have been repeatedly struck. The Dr. himself, once saw a discharge fall on a row of Dormitories and pass to the ground. Don
256 Aug 1st 1851 Smith List Cohesion film of water. [[image of drawing]] Reflected a beam of light from a soap film on a shallow cylinder, found the light polarized as from a surface of water. Next transmitted the beam through the film, as if through a plate of glass,found the beam polarized at right angles to the plane in which it was polarized by reflection.. The film of water in this case acted as a plate of glass [[word circled]] unannealed [[word circled]] [[image of a drawing]] When a quantity of water is found on a table, and on the rounded edge of the liquid a small piece of paper is placed, the latter will be drawn on to the liquid as if acted on by an accelerating force.. The explanation of this phenomenon is not difficult. Let a. b. c be the water,and e. f. the paper, then the curvature between [[underline]] b [[underline]] and [[underline]] e [[/underline]] will be greater than between b and f, and consequently the action between the surface of water, and the paper, will be greater towards [[underline]] b [[underline]] [[underline]] e [[/underline]] than b. f.. On this subject, I may mention that the workmen of the S.I. building informed me this morning that [[strikethrough]] the [[/strikethrough]] a thick rope (2 inches diam.) had spread in length on account of the rain at least 2 feet. This rope is used for hoisting the [[end page]] [[start page]] Aug 1st 1851 Cohesion 257 mortar and stones for the walls of the edifice, and has been subjected to the rain of yesterday. I yesterday blew a bubble on the surface of a basin of beeswax which had been previously heated. After the wax was cold,the bubble was broken, and the depth of the pit formed by the contractile fore of the bubble measured. The depth was about a 1/10 of an inch, the diameter of the bubble was about the same. I propose repeating this experiment with more care. It affords a ready method of determining the contractile form of a bubble. Since the contractile force is in the inverse ratio to the diameter, a very minute bubble must exert a very great force on the enclosed material, as for example on a minute portion of air. Indeed this force may be sufficient to compress the air almost into a liquid state, or at least to render it invisible even with the aid of a microscope. If we suppose the air removed a void space would exist between the atoms arranged as a sphere, and this would give case on the same principle to an immense force between the atoms of the water. In the case of freezing the [[strikethrough]] water [[/strikethrough]] air disolved in water is expelled. May this be produced by the crystaline form of arrangement of water thus [[image - dots]] While water is formed by atoms thus [[image - dots]] uniformly distributed through the space, the effect of heat
258 Aug 1st 1851 sound is to break down the crystaline arrangement. The air given off in the case of freezing would be more rarified than that contained in the water [[line drawn across page]] [[image of a tuning fork]] Placed a tuning fork against a brick wall, found little or no resonance. Against the door through the same [[strikeout]] wall loud resonance.The fork was placed against the valve of the door. Also placed the same fork on the wooden floor of the room, resonance tolerably loud- same fork on stone flag floor little or no resonance was observed. M Perrole (Nicholsons [[?]] 4 to vol 1 page 411) found that for conveying sound to the ears, light wood is better than metal, string worse than either of the preceding. In constructing the microphone, use light wood. Instrument of cane would perhaps answer well, chewed paper in the ear. [[image]] Fork on edge of table gives feeble resonance on the middle loud . the whole table therefor vibrates as a whole. [[end page]] [[start page]] Aug 1st 1851 [[short squiggly line]] sound through walls 259 [[image]] Fork placed again the door, sound heard as loud on the other side as if no door intervened. Next fork placed against stone wall sound distinctly heard, but not loud by resonance but by conduction. Fork placed against one end of wall, six feet long 2 1/2 thick one ear closed, the other against end of wall, sound distinctly heard by conduction. Aug 4th Cohesion Cast lead into the form of a square prism. Broke it with a drawing apparatus. the end assumed the form of a cross with a slight depression in the centre. [[image]] The same external form produced in each case the same appearance. Next a cylindrical pile of lead 3/4 of an inch in diameter . (The presu above mentioned was nearly an inch) was drawn apart by the same apparatus. In this case the fracture presented an appearance of which the sketch is a section. [[image]] The same appearance was exhibited in several experiments showing that they were not accidental. [[image]] When a lip of lead is broken, the separation takes place in the centre.
260 Aug 5th 1851 [[short squiggly line]] Cohesion S.I. From these experiments it appears that the separation of the particles in the breaking of a rod of a soft metal takes place first in the axis of the bar, and then probably extends outwards. [[image]] The cause of this action is to be found in the greater mobility of the particles at the surface, by which they are allowed to slip on each other; and thus to elongate the surface, while the middle thread of particles, being surrounded by other particles, and laterally pressed on all sides are ridged, and are obliged to separate when sufficient force is applied. This effect is directly opposite to that of the breaking of a cylinder of water. This takes place at the surface, or rather circumference and [[word circled]] proceeds [[/word circled]] inward. When the experiment is tried with a piece of putty, which may be considered as intermediate between the two extremes of perfectly rigid and perfectly liquid, the effect is as it were intermediate, the putty breaks entirely across at the same time [[?]] a little at the point of breaking is becoming less in diameter. [[end page]] [[start page]] Aug 5th 1851 [[short squiggly line]] Cohesion S.I 261 [[image]] Dona, in the Annales de chem, asserts that water deprived of air, boils at a very high temperature , 135 [[degree symbol]] centigrade. To test this, a quantity of perfectly transparent ice was melted in a vacuum produced by the air pump (not [[?]] of course) The water thus produced was heated in the same vessel in which it melted by a spirit lamp. It gave off no bubbles, and boiled by a delicate thermometer at 214 of the arbitrary scale employed. This water was removed from the vessel, and its place supplied with water from the cistern of rain water, which boiled at precisely the same temperature, thus showing no difference in the boiling point. [[short line drawn on page]] Princeton Aug 9th Attempted with Prof McCullough to detect depolarization in water between freezing and [[?]] 40 the maximum density, but was unsuccessful. The tube in which the water was contained became filled in each attempt with ice which was not transparent. The experiment must be tried under other arrangements. Suggested the propriety of experimenting for the same purpose with [[word circled]] glauber [[/word circled]] salts, prepare a saturated solution, and after well boiling, cork and suffer to cool, examine it in this state for depolarization of light. [[image]] Boiled water in glass vessel, found that the temperature was again with another thermometer 214, Marett Ann de Chem vol 53rd [[?]] finds that glass washed with sulphurcy acid
262 Aug 9th Cohesion causes water to boil at 210[[degree symbol]], or 105 + 106 centigrade - The acid increases the adhesion of the water - also that a glass vessel of which the bottom is covered with flower of sulphur, boils water at 99+ lower than a metal vessel [[image of a star symbol]] These experiments show the cohesion of the water and the necesity of a surface to produce boiling , other wise why should not the heating of the whole mass up to 210 cause boiling in the centre at a distance from the surface, the action of the surface cannot extend but to a very small distance. Also in all the experiments of [[?]], the temperature of the vapor was less than that of the water from which it was produced. It follows from this as has been remarked by Magnus (An de Chem ) that more force is required to separate or evaporate the atoms of water, there is sufficient to sustain the vapour in its state when formed. [[image of dots]] The questioned may be asked how water which has so great an attraction for itself, can pass into vapour when the pressure is removed. The answer is that probably the evaporization takes place in the exterior film. The boiling under reduced pressure takes place apparently from the middle of the mass. I allude to the experiment of boiling produced by the application of cold water to a [[word circled]] bott [[/word circled]]head of heated water. [[image of a star symbol]] In this exp the adhesion of the glass to the water is diminished. [[end page]] [[start page]] Aug 9th 263 [[image of two short vertical lines]] Repeated the experiment of Gay Lussac of throwing metalic filings into water heated in a glass vessel, the temperature of the boiling point was lowered and the evolution of steam much more copious. The same effect is produced, but not so intensely, when pounded glass is added to the heated water. The explanation of this is not clear. [[image]] Salt and water with litmus, when exposed in a cylindrical vessel, freezes around the circumference, the salt and litmus is found in the middle, the process of freezing expels the foreign matter. (Berzilius) vol [[?]] 19th Aug To coat a substance with lamp black so as to show the siff attraction of water, hold the article over a piece of burning camphor, an exceedingly fine coating of the black is evenly distributed over the surface. A platinum disk was covered in this way and exhibited the water most beautifully. [[image]] If a drop of oil be placed on the disk, prepared as above, it will adhere to the lamp black, oil has a greater attraction for most bodies, than for itself - if a drop of water be brought into contact with the oil, which adheres to the charcoal, the two will adhere together. [[image]] The contractile force is very prettily exhibited by a large drop of oil on water, thrown into an irregular form, by a wire, as for example, as at a. The contractile force at a carries this point outward, and the action at c d carry them inward.
264 Aug 13th 1851 Cohesion Princeton By a reference to [[word circled]] Pouillets [[/word circled]] Physique, it will be seen that water in spouting horizontally from a square hole in the plane side of a vessel, assumes the following forms analogous to that of the broken lead [page 259]. [[image of four shapes]] In this case as well as in that of the lead, the surface moves with more velocity than the interior. The former therefore caves in and leaves the angles protuberant. The oscillations of the water produces the effect of the salient points at right angles to the side of the square. The two phenomena apparently differ in this respect. In the crushing of pieces of stone on metal the same appearance is exhibited, the sides of the cube break off in the [[image]] form of pyramids, leaving an appearance smaller to that seen on the figure. see 7th British Association Reports : - a plate is exhibited: [[image]] When a soap bubble is blown between two rings of brass, so as to form a cylinder between them, the several curvatures are in proportion to the pressure, along the cylindrical portion there is but one curvature, or rather a curvature in one direction, while at either end the curvature takes place in two directions, and therefore this double curvature exerts the same pressure in wards with half the curvature, or in other words the radius of the spherical ends is twice that of the cylinder. [[end page]] [[start page]] Princeton Aug 13 [[short squiggly line]] Cohesion 265 The foregoing is a beautiful illustration of the theory of capillarity. To exhibit this experiment in the simplest manner, the two rings should be supported at a movable distance by a rack and [[word circled]] pinion [[/word circled]] motion. [[image]] Thus without some contrivance of this kind, we find considerable difficulty in filling the space with a cylinder. [[short line on page separating paragraphs]] [[image]] Observed a remarkable phenomenon with reference to a circular piece of soap which was placed in the water on the surface of a plate. It was suffered to remain a few moments on the bottom of the plate under the water, after its under side had been rubbed on the plate, to make the soap water, and in the short space of time I have mentioned, so great an adhesion took place that the cake could not be removed by the fingers, but I was obliged to use a paper cutter to separate the two surfaces. This effect was not due to the drying of the surfaces together, because the effect took place under water! [[image]] When two bubles are produced by drawing apart the two rings to which they are attached, a neck is exhibited at a which closes itself, and produces a buble.- thus: see figure! [[image]] the same effect has been observed by Plateau in the case of globules of oil in water rendered lighter by alcohol. A similar phenomenon is mentioned by [[word circled]] Buillets [[/word circled]] from the analysis of [[?]]
266 Princeton Aug 13th 1851 [[short squiggly line]] Cohesion Break a piece of gilded wire, will the gilding be opened so as to exhibit the naked metal? [[image]] I am inabled this morning to make the largest cylindrical bubble by means of a funnel, the bubble touched at its lower end to a plate of soap water. In this experiment, the middle buble is beautifully shown. The buble can be made very large by continuing to blow while the funnel is gradually elevated from the place. Why does the imbibation of water expand wood? When two films of soap water are plunged parallel into soap water, they collapse into one, the attraction of the water between draws them together {see preceding exp - } [[image]] When two pieces of wood 6 inches and an inch wide ware floated on water they rush together. (Perhaps I have mentioned this before] Also when two slips of paper are wet and lifted out of water if they are made to touch at the lower ends, they rush together nearly to the top Thus: [[image]] Should not as in this case [[strikeout]] a rope be shortened by the paper being drawn together in their oblique direction across the length of the rope. This will explain the shrinking of a rope, but why should the pores of wood and of paper be expanded by imbibing water? [[end page]] [[start page]] Princeton Aug 13 1851 [[short squiggly line]] Cohesion 267 The paper in the foregoing experiments are drawn together with great rapidity and adhear with so much tenacity that the parts give way before they separate. In the experiment on the last page the one at the bottom the two bubles may be found so lowly that no third bubble is produced. The generation of the middle bubble as well as its size, depends on the velocity with which the two discs or circles are seperated. The contratile force gives a certain velocity to the contracting orifice of the bubble and of the seperation of the two bubbles is more rapid than this, the film between them will be drawn out into a cylinder each end of which will have a contractile force tending to close it and to convert it into a bubble. Why does it not contract [[?]] at the middle? Because either end at the moment of separation is under the contractile force at each bubble and this by a dynamic action closes each end rather then the middle of the small cylinder. But why does wood expand when water is imbibed? Prof McCullough informes me that the film of water which adheres to a glass tube may be exhibited by heating the tube and driving the moisture into the upper part of the tube to be condensed on a cooler part. This effect is probably not due to the moisture of the air. If this were the case, Prof Mc remarks the effect might be shown by flattening a tube so as to diminish the quantity of air, while the surface of glass remains the same.
268 Princeton } Aug 13th - 1851 }Cohesion Prof. Mc C informs that when zinc is melted in iron pots, the liquid metal penetrates the iron and amalgamates it. The pots or crucibles in this case are made of cast iron. Zinc and cast iron when melted, do not mingle so as to form an alloy. This fact is in accordance with the experiment I made with copper and silver showing the penetration of the former by the latter. [[image - beaker or crucible filled with large and small shot]] Fine and coarse shot placed in the same vessel, and then shaken, the course comes to the surface. This I am informed is the case with pounded and course stone in a road. The fact that the pelical [[maybe pellicle??]] in christalization of a salt by evaporizing the water is formed at the surface of the water where the rarifaction of the substance is found, is an interesting fact, showing that the evaporation goes on more rapidly at this place. [[Separate later note]] Examine this pelical with polarized light, May 1862 Aug 14th. According to Pidet [[?]] - homogeneous organic substances augment equally in all directions by imbibing moisture. Also paper parchment and other substances composed of filaments crossing in every directions should comport themselves as homogenous materials. Those of parallel fibre experience much more swelling in a direction perpendicular to the length - [[image - sketch of a table]] Edgeworth's hygrometer piece of soft wood cut cross grain with sharp nails as legs. [[end page]] [[start page]] Princeton Aug 14th 1851 [[short squiggly line]] 269 [[image in margin]] When drops of water are let fall into oil they sometimes, perhaps always if let fall from a small height, adhere to the under surface of the oil. I am not able just now to explain this phenomenon. A large rope used at the Smith Inst for hoisting stone, contracted about 4 percent and elevated several hundred pounds after a shower. For some remarks on the breaking of metal rods by traction , see Ann de Physique, vol 3 - ann de chim for [[?]] 12 vol [[?]] The bar was observed to elongate by jumps. For a view of the crestalographic theory see [[word circled]] Bansdrimont's [[/word circled]] elements de chim. [[image]] Small depth of water thrown on a plate, on one side of this as at e, a small quantity of ether poured on a singular motion is observed along the line joining the two fluids. The ether ditracts, or is attracted by the plate stronger than the water is. The latter therefore contracts on itself, also the contact of the ether and the water lessens the attraction of the superficial film of the water, causes this to break and to throw motes of lamp black up the curved surface, while they are drawn along the bottom to supply the current which takes place at the surface. That the contact of the ether produces the effect to break the film, is proved by direct experiment. Touch a soap buble with ether and it flies apart.
270 Princeton Aug 15th 1851 Cohesion [[Image]] The effect mentioned on the opposite page with the ether, will be understood by the annexed diagram, the current is indicated by the arrows. That the motion can be produced by the diminution of the contractile force, is show by the great force of contraction is exerted by the rupture of a film on a ring, the water is thrown to a considerable distance by an excelerating force. The same effect is produced by pouring a few drops of alcohol on a plate containing a thin film of water. It is necessary to the proper exhibition of this experiment that the plate should by perfectly clean, and this may be effected by washing the surface with hartshorn. A perfectly clean surface may also be obtained by splitting a plate of mica. Also a similar action ought to be exhibited by plunging the end of a heated wire into the film on the surface of a plate of water. To ascertain the relative hesion of different liquids for different solids, drops placed on the solids of different liquids, the relative force determined by the spreading or by the -- For a paper on Capillarity, see Annals de Chem, vol 32, 3rd series, May 1851. The following facts are from this. [[end page]] [[start page]] Princeton Aug 15th 1851 || Cohision 271 Needles cannot be made to float on ether, alcohol or naptha, __ substances which rapidly evaporate, __ all substances put on naptha are covered, even paper is precipitated to the bottom, and there disengages the air contained in its pours. Also naptha, while water, alcohol, ether, and so on extend themselves spread by dispersion, forming a circle of about two centimeters, of which the circumference exhibits an accumulation of the liquid. On water, oil, or mercury, naptha makes beautiful coloured rings. Lighter bodies made to rest at the bottom of a vessel of mercury. (Annales de Chem May 1851) Carbonic acid would be compressed into a liquid. Heat diminishes the cohesive force in tubes from boiling to freezing in the ratio of 4 to 3. {The same-} Christalographic theory by Delafosse, Professor of the faculty of science of Paris. Note to ask him to send modes. Compt Rendu, March 10th 1851.
272 [[strikethrough]] Nov 14th 1851 [[squiggle]] Smithsonian Institute Crushing of Stone I have been engaged for several days as one of a commission to examine the building stone (marble) proposed for the addition to the capitol. Found some curious results which will be found in the report. The most unexpected was that of the effect of placing a piece of lead, a thin plate, between the stone and the iron plates, between which it is compressed. [[hand drawn illustration to the left of the explanation. Illustration is of a column, with a, b, c, d in a vertical line beside.]] a + b represent the compressing plates and c + d plates of lead placed between to equalize the pressure, which might be required on account of the want of perfect parallelism of the upper and lower face of the stone. At least this was the object in interposing the sheets of lead. The unexpected result was that with the soft metal thus interposed the crushing resistance of the stone was not more than half that of the stone without the lead, and the surface brought to near parallelism. This was shown by using felt, in every case the difference was surprisingly great. The fact may be accounted for referring it to another fact, namely that the stone in crushing, always gives way so as to leave a pyramid or a cone as the case may be, on account of the rise of a cylinder or a cube. Thus generally a wedge of stone is forced off on each side, leaving the pyramid at the base. [[ to the left, a small hand drawn illustration of a mountain in a square a on top, b o the side]] Now if a an equable and yielding pressure be employed, these wedges will first be thrown off and afterwards the apex will go down. Suppose the wedges will tend to [[end page]] [[start page]] S.I. Nov 14th 1851 273 be thrown off with a pressure of say 20000 lbs per square inch, then if the pressure be a soft equable one, the wedges will give way at this pressure, and after this the solid iron of the plate will come down on the apex of the pyramid and crush it though it might in itself resist with a power of 40000 lbs to the inch. With a [[faintly circled]] ridge parallel pressure, the whole must give way together, and have the paradoxical results before mentioned. The stones were afterwards all ground to perfect parallelism in an iron frame, placed perfectly flat and parallel on the two sides on an iron planing machine. [[hand-drawn illustration of side by side boxes on a horizontal position]] The stones were placed in this frame leaving a small portion projecting on the upper and lower side, and then ground down on a flat stone with sand + after this the effects were found to be double of that with the lead and greater than with the felt. While the commission was in session this evening, and the table was illuminated with 8 sperm candles of which the wicks were twisted, the wick of each candle was turned at right angles to the axis of the candle and made to point directly north. In the course of 15 minutes, they were all found pointing to the East, all having turned in a direction to increase the twist.
274 S. Inst No 15th 1851 Made an experiment this evening on the freezing of moist sand wonder if possible to throw some light on the phenomenon noticed in the crystaline freezing of soft earth. For this purpose a quantity of sand half a pint , was put into a copper vessel and submitted to the freezing mixture, the result was that the whole became solid. On conversing with a [[insertion mark]] an assistant by the name of cole , a young man on the subject he informed me that he first observed the phenomenon when a boy,under the following circumstances. His father dug a cellar in the autumn, and left the porous sand thrown out of the excavation in heaps, in the [[underlined]] spring [[underlined]] he observed the arborescent crystalization every morning after a previous warm day, and a cold night. He supposed the affect was in some way due to evaporization. From these hints, I have found the following definite hypotheis as to the cause,- The phenomenon is produced by the evaporization of a stratum of earth below one subjected to the freezing action of the air, and as an essential condition it is necessary that the season be such that the freezing at night may be less than the thawing in the day. Thus let the [[image]] thawing in day time desend to b and the freezing in the night to a, than that of the stratum ab during the night will be moist and more heated then that of the surface, it will therefore give off vapour which coming to the surface will be frozen, but why in columnar form? Exp on this! [[end page]] [[start page]] S. Inst Nov 28 [[squiggly line]] 275 It is well known that bubbles of air apparently adhere to the side of a tumbler of water, when placed under the exhausted receiver. In observing this phenomenon this evening, the cause of the adhesion presented itself to my mind. [[image]] The cause of the apparent cohesion appears to be this.
276 Washington March 17th 1852 [[short squiggly line]] [[image of drawing]] Experimented on an apparatus for giving motion to air which I had made a year or two ago. Found that on whirling this apparatus the air was thrown out with considerable force so as to be felt or its motion indicated with the flame of a candle as many as four feet on all sides, the drawing up effects were however very slight. [[image]] The agitation below did not extend to the distance of more than 6 inches, while in the plain of the equator of rotation it was perceptible at the distance of, as I have mentioned before, of four feet. [[image]] The whirl was then put into a barrel on the bottom of which a small quantity of cotton was placed. The whirl then drew the cotton from the bottom and threw it out of the barrel. This explains the effect produced in a cylindrical vessel filled with water in which a whirling apparatus is placed. In this case three currents are observed. [[image]] The current in the axis is rather a vacuum down which bodies fall. The water is thrown off to the side of the vessel and is heaped up at the sides, then sucks to supply the upward motion at the centre. [[end page]] [[start page]] Washington March 24 1852 277 [[image]] Experimented with Mr. Espy on the effect of the air rushing into the lower open end of a stove pipe. To this purpose a fire of pine boards was kindled in one of the air shafts in the wall of the east wing of the smithsonian building. The orifice was closed with a piece of sheet iron through a hole in which the the upper end of the bent stove pipe was inserted. The fire in the shaft rarefied the air, and this made a draft which was supplied through the mouth of the pipe a. The draft however was not very strong, the greatest difference in [[image]] the altitude of water in the two legs of a glass syphon was about 4/10 of an inch. To mark the lines of action, a circular plate of iron heated to nearly redness was held under the mouth of the pipe, and on this plate a quantity of rosin was scattered in order to produce a dense smoke. The appearance produced was like that exhibited in figure 3. The smoke was drawn into the axis when the plate was held about 3 inches from the mouth of the pipe. When the plate was held nearer the pipe, the smoke was drawn in nearly horizontally. When farther off, less horizontally. When the plate was removed, and a surface of water substituted, a slight elevation of the liquid was produced. [see figure on [next-page].
278 [[image]] In one or two cases, a whirl wind was produced in the use of the heated plate which extended downwards from the mouth of the pipe to the distance of 8 inches. Also in all the arrangements, a whirling motion was produced occasionally sometimes in one direction and sometimes in the other. The whirl was an accidental effect either of the unequal [[strikeout]] action of the air in its approach on different sides to the excs, or in its oblique action on the substances thrown into to the currents to reach their direction. The draft was not sufficiently grat to produce very well marked effects; we propose to repeat the experiment with a blowing machine. [[short squiggly line]] April 3rd Accompanied Mr Espy to Rider's Machine shop in order to observe the effect produced by a centrifugal blowing machine. The draft was quite powerful through the axis of a stove pipe. Probably about equal [[strikeout]] in pressure of half an inch of mercury. [[image]] [[end page]] [[start page]] 279 [[piece of paper pasted onto notebook]] Smithsonian Inst March 29th 1852 My Dear Miss Dix [[image of drawing]]
280 April 12 1852 [[short squiggly line]] Smith Inst Galvanic Light [[image in left margin]] Made an observation on the galvanic light from a globule of mercury, observed the spark through a prism, found a remarkable break in the continuity of the spectrum, the follow colours were apparent, namely part of the red, the orange, the yellow and part of the green, the blue was wanting, and the indigo and purple appeared at the farther end. The light some times varied so as to exhibit occasionally more of the red- and sometimes more of the blue. The paper in the margin gives the appearance which was most generally exhibited. The same effect was observed with [[strikeout]] by [[/strikeout]] the spark on either side of the globule, as the point of the wire of the rod of the pendulum passed out of the globule. I should have mentioned that the light was produced by breaking the circuit of a galvanic batter by means of a pendulum point on the end of the wire of the bob of a pendulum. The spark was observed [[strikeout]] by [[/strikeout]] in breaking the circuit by an upward motion of this point, so as to draw the plutina perpendicularly out of the mercury - the result however was the same , the violet part of the spectrum was in all cases widely separated from the orange. [[end page]] [[start page]] April 12th 1852 [[short squiggly line]] 281 Experiments were also made on the spark from two surfaces of copper, but in this case the spectrum was continuous, though the quality of the light varied [[strikeout]] from time to time exhibiting at intervals a great amount of red. Also observed the spark from the separation of iron + copper. For this purpose the end of a copper wire forming a part of the circuit was rubbed along a file. The spectrum was also in this case continuous, but exhibited a large amount of red. When the spark from this arrangement was observed by the naked eye, it exhibited a series of colours red, white, blue. It would afford an interesting field of research to make a series of experiments on the physical properties of light (electrical) in the different gases with the apparatus used by Faraday. If the theory of the absorption of certain rays [[strikeout]] is [[/strikeout]] by different gases be true, some interesting results might be expected. For this purpose however we ought to have an apparatus expressly for the purpose. [[piece of paper attached to bottom of page, with writing and image drawing]] Spectrum of the Electric Spark from combustion of Mercury Violet Indigo Blue Green Yellow Orange Red 1/3 1/5 1/3 1/2
282 In reflecting on the phenomenon of crystalization I have come to the following conclusion. The molecular form which causes chemical attraction is polar, because when two substances which unite chemically combine the force of the each neutralizes that of the other in the manner analogous to the neutralization of the opposite poles of two magnets. [[image]] Thus when s + n are brought near each other, they neutralize the action of each other on the third pole. So when chemical combination takes places a neutralization is the result. We may suppose that all [[image]] matter is polar, but that in the state of air and liquid the polarity is not perceptible, [[image]] on account of the constant motion of vibration and rotation of the atoms, but when the temperature is so much reduced that these atoms are allowed to approach and their polar action to manifest itself the atoms then form themselves into groups of molecules as represented in the lower figure, each one of these having a polarity acting at a much greater distance than the polarity of the atoms for the same reason that the polarity [[end page]] [[start page]] 283 of a long magnet is greater than that of a small one in which the poles are so near that they almost entirely neutralize each other, and this is the case, though a long magnet is made up of a large number of small ones S- - - - - N, the several parts of which neutralize each other. For this reason the crystalized groups as shown in figure 2nd cannot turn round, and hence the mass is a solid. No slipping can take place among the parts as in figure [[underlined]] one [[[underlined]] I suppose the liquid state to be produced by the vibrations imparted to the atoms which form the groups of crystals in figu 2, & that this motion destroys their crystaline structure, reduces the whole to the form of Fig 1 [[&]] suffers a contraction to take place in the whole volum though the atoms are really farther apart & the contration is caused by the breaking down of the elementary crystals.
[[start page]] 284 [[vertical squiggle]]Smith. Inst. May 5 1852[[vertical squiggle]] Capillarity A glass tube of .0000507 of an inch would draw up water by capillary force to the height of 616.6 inches, when the other end is immersed in alcohol. This is equal to 57 feet 4 inches of water nearly equal to two atmospheres. Saturday Evening July 28 1855 [[vertical squiggle]] A long time has elapsed since I have made my entries in this book, my time and thoughts have been absorbed by the affairs of the Smithsonian, and in some case in defending myself against malicious attacks. This evening in company with Prof Schaeffer, Mr Suxton [[strikeout]] Mr. Lanell and Dr Lawrence Smith, I reapeated with [[word circled]] Rhumkoff's [[/word circled]] apparatus all the principal phenomena of diamagnetism and the influence of a current of galvanism in twisting the plane of polarization of light in a ray transmitted through heavy glass. I observed in repeating this experiment, which was originally devised by me in 1837, that colour was produced, thus showing that a polarizing structure [[end page]] [[start page]] 285 was given to the glass on which the experiments were made. I know not whether this result is produced on water. It would be well to try this, and also what effect is produced on the transmitted ray through water, which has been compressed in the apparatus of Oersted. Also the effect on a ray through sulphate of soda, saturated but not crystalized. What effect is produced on quartz which already possess the property of circular polarization. Perhaps most of these experiments have been tried. The most striking experiment in diamagnetism is that with the [[image]] copper cube suspended between the poles of the electro magnet. Though the cube is made to revolve with such rapidity as to appear like a cylinder by the untwisting of the suspension thread, it is instantaneously stopped, as if suddenly brought in contact with soft [[?]]. There is not apparent oscillation; the cessation of motion is instantaneous. The diamagnetism of flame is quite interesting. A common tallow candle was placed between the poles, and at the moment completing the current through the wire around the soft iron, the flame was bulged out at the sides so as to be increased in the line at right angles to that which joined
[[margin]] 286 July 28th 1855 [[wavy line]] the poles. It is said that greater the amount of carbon in the flame, the greater will be the the diamagnetic result. We did not find that the spark lamp flame gave such striking results. We also repeated an experiment first mentioned by Dr. Page and which he accidentally made, by means of the large electro magnetic apparatus constructed at the expense of the government. It is this, when the circuit of an electrical current which passes round a core of soft iron is broken at a point in space near the pole or poles of the electro magnet, a loud snap will be produced, and if the intensity of the current was much increased in the neighborhood of the pole. This experiment was tried, and with perfect success. When the two ends of a wire, through which the currents from a battery of 20 cups of Bunsons battery was flowing, were separated at a distance from the poles of the [[word circled]] Rhumkorff [[word circled]] apparatus, the snap was quite feeble, but when the break was made between the two poles, the effect was quite loud. At first sight it appeared probable that the effect was produced by the sudden demagnitization of the soft iron which [[end page]] [[start page]] 287 had previously a higher degree of induction in the wave, but this was proved not to be the case by repeating the experiment with a large permanent horse shoe magnet. [[image]] The effect was the same with this, though the wires of the battery were placed as in Fig one, so as to produce no action of any account on the magnet. When the break was made at a little distance from the poles of the magnet,the snap was feeble. When made near the poles, it was quite loud. The difference in the intensity was too great to admit of doubt as to the reality of the phenomenon. Also when the separation of the wires was made between the two poles, the flame took a diamagnetic form,and arranged itself in all cases at right angles to the line joining the axis or poles of the magnetic. I say arranged itself, perhaps this is not the proper expression. I ought to have said spontaneously appeared in the diamagnetic condition. Experiment on this- I am impressed with the fact that the demagnetic condition of matter can be explained with other phenomena by
[[start page]] 288 supposing a fluid filling all space and gross matter. The particles of matter are polar, because the attraction between them is neutralized. This polarization determined in one direction may produce the magnetic phenomena. Again the magnetic polarization may repeat - the natural electricity of a conductor and direct it in a transverse position. [[ 3 checks towards right side of page]] Since writing before this evening in this book, I have made a series of observations and experiments in sound. I have been appointed one of a commission to inspect the plans proposed for arranging the wings of the capitol expansion in regard to light, heat, and sound. A lecture room has been constructed under my direction which completely answers the purpose. [[horizontal line halfway across page]] [[hand drawn illustration to the left of the following paragraph]] Made experiments with a silver crucible, a thermometer with a large bulb, and a short lamp to ascertain whether any change took place in the boiling point of a liquid by transmitting a galvanic current through it.. The 1/10 of a degree could be noted, but no change due to the electrical current could be or [[end page]] [[start page]] 289 rather was established. I was however surprised at the fluctuations of the boiling point. It did not remain stationary from minute to minute, but constantly varied from half a degree below to as much above 212°. Aug 7th 1855 While experimenting on the freezing of the stone for the capitol, I was surprised to see that large pices of ice half a cubic foot in capacity were frozen to a carpet which was put over the lumps to keep them from [[strikeout]] freezing [[/strikeout]] melting. The freezing was so complete, that the large lumps weighing twenty pounds, could be lifted up from the box in which they were contained. I was at a loss to account for this, and inorder to ascertain whether it was produced by the original cold of the ice, or was due to heat absorbed during the melting of the other portion, I caused holes to be bored in the blocks of ice and inserted into these thermometers, but in no case could I see the instrument descend to the freezing point. It takes place apparently with ice of all kinds, with that which has been exposed for several days to slow melting, as well as with that which is just taken out of the ice house. The best way to exhibit the phenomenon, is to place a small pice of ice on a dry sponge. The sponge will absorb the surplus - [[image]] water, and the film which remains will be frozen to the surface of the sponge.
290 Aug 7th 1855 [[short squiggly line]] A few years ago Gen Totten asked me to explain the following phenomenon. When a small quantity of wine is thrown on to small pieces ice in a tumbler, and a spoon which has been warmed in the mouth is pressed down on the ice, the latter is melted at the point of contact into a cavity which exactly fits the concavity of the spoon, now if the spoon be kept quiescent for a few moments, the ice will be frozen to it, so that a large piece may be lifted out of the cup. The idea which occurred to me as to the explanation was that the phenomenon was caused by the rapid melting of the ice in the act of combining with the alcohol of the wine. To bring this hypothesis to the test of experiment, I immersed a thermometer into melting ice, and afterwards poured in a small quantity of alcohol. The temperature fell 10 degrees. Though the unison of water and alcohol is attended with an increase of temperature,yet the affinity of the two is so great, that they united when the water is in a solid state, and the cold produced by liquefaction is greater than the heat by combination. [[end page]] [[start page]] 291 When two pieces of ice are reduced on one surface of each to a plain surface, and three surfaces brought in contact they will freeze in a few minutes so as to be solid. This phenomenon belongs to that of the ice freezing to the old carpet mentioned page 189. I attempted to day to asertain whether the temperature of the interior of a mass of ice was increased or diminished by rapidly melting the outer surface, for this purpose I placed the point of junction of two metals copper and iron, in a piece of ice, while the other extremity of the wires were connected with a galvanometer, but the result was not satisfactory, the galvanometer was not in good condition, nor properly placed. [[end page]]
292 May 18th 1858 On Friday last -May 14th, a house was struck with lightning in Georgetown, and on saturday the 15th, another was struck in Washington in 17th street, north of the avenue. The house in georgetown was in the street near the [[?]] Hotel, a little north on the right hand side. I visited last evening in company with Professor Schaeffer both of these houses, and found the phenomena exhibited very instructive. The conditions and effects in both cases were almost identically the same. In the case of the house in Georgetown the lightning struck the lightning rod, melted the point, passed down the stem to the level of the roof, then turned at angles from the rod, followed the wet clapboard along the gables end of the building horizontally to a tin gutter along the eaves, thence down a tin gutter pipe to the roof of a back building, thence along another tin gutter on the eaves of the back building to the point within the house opposite the [[end page]] [[start page]] 293 gas pipe against the inner wall. It then pierced a hole in the plaster after entering by two nails, and finally was it is supposed discharged into the earth along the train of pipes which supplied the city with gas. [[image of drawing]] The bolt struck the rod at a, melted the point- left the stem at b passed horizontally splitting the clapboard to e, then along a gutter horizontally towards the farther end of the house, thence down a pipe to d, and then going another gutter to c where it entered the house through some nails. The discharge divided in passing into the house between two nails, apart whent directly to the gas pipe which was immediately opposite on the inner wall the point where it entered, and the other passed on the other side of the corner post of the building, and running along the upper surface of the ceiling perforated it opposite about the middle of the length of a branch of the same gas pipe and left no other trace of its course. The lightning rod was of iron about
294 half an inch in diameter terminated with a point of some metal more readily fusible than platinum. It went into the dry earth, according to the owner of the house, about 5 feet, and terminated under a stone wall which formed one end of a paved alley the house the other. The rod entered the ground through the brick pavement of this alley, and consequently terminated in earth well beaten by the travels over it. The stem of the rod was fastened to the clapboards of the gable end of the house by iron eyes and glass cylinders for insulation, one of these cylinders which was between the top of the rod and the place where the discharge left the stem, was broken and thrown to the ground, indicating a violent directive force probably due to the want of perfect conduction or commutive with the earth. Several persons were in the house at the time but none of these were injured. [[end page]] [[start page]] 295 though they felt the shock. one young woman was in the room where the discharge pierced the ceiling near the horizontal gas pipe. The other house was struck in a remarkably similar manner.[[image]] the lightning rod was however on the north gable of the building. The electricity left the rod in whole or in part probable at the apex of the roof, passed down the coping at the end of the roof, which formed with the roof, a union rendered water tight by a lining of tin to keep out the water from running down between the perendicular wall, and the roof. Down this tin path the electricity descended until it arrived at the tin gutter, which caught the water from the roof, and then passed along this southward until it met a perpendicular tin tube letting the water from the gutter. [[image]] The course of the discharge is shown by the dotted line in the annexed sketch. The lightning entered the house at d, having descended from the point a of the lightning rod. In its course, it was making its way to the earth, and took the line of least resistance to the gas pipe, which was imbedded in the wall of the large house about 15 inches from the points where the charge pierced the brick wall of the smaller building. The penetration was through
295 May 18th 1858 [[squiggly line]] House struck with lightning a brick wall nine inches thick. It probably passed through between two bricks and not through the solid material of the baked brick. This is the more probable, because the work view of Washing are in the habit of putting but little mortar between the bricks, and rendering the whole apparently solid by a plastering along the joinings. The cause of the leaving of the rod in both of these instances is very evident. The rods in both cases were connected with the earth very imperfectly not desending into the earth, and that too dry earth more than five feet, while the glass pipe was connected with a train of paper or perfect induction for several miles in extent. The induction was therefore in both cases very great, the attraction consequently of the descending discharge for the gas pipe very intense, so that the paths in the lines we have described was the most natural. The exhibition of the path of the electricity to the earth in these two cases was very instructive, and clearly indicates the importants of connecting the lower end of the lightning rod with the gas pipe in the [[end page]] [[start page]] May 18th 1858 [[squiggly line]] House struck with lightning 296 street by means of a good conductor. I think it probable that though the earth be a good conductor of galvanism, yet a sudden discharge of ordinary electricity of high tension would rebound from the earth, and a rod receiving a stroke would tend to suffer it to fly off if the lower end were merely driven into the ground, particularly if the latter were dry. The gas pipes may act as conductors, and transmit the most powerful charge to the earth without mischief. The lightning however made to descend along the gas pipe, must enter the house by piercing the walls, and should any person be in the line of its path, a serious accident would follow. In the case of the house last described, a female was sitting with her back to the line of the gas pipe along which the discharge descended. Though the passage was marked by the blackning of the plaster along the course of the gas pipe, the female received no permanent injury, tho she was stunned for a time, and for an hour after heard a ringing in her ears.
297 Aug 2nd 1858 May not the fact that water does not adhere to a polished surface of iron, such as a razor, be due to the want of minute curvature towar the metal, as in the case of [[image]] a rough surface with salient points. The attraction of the drop of water for the projecting point will be greater at a than at any other point, in account of the great curvature of that point which tends to press it closer to the metal. Or the fact may be connected with the condition that if the attraction of a plate for a liquid greater than half the attraction of the liquid for itself, the liquid will rise along the surface of the plate. Mr Rendill [[?]] informs me that during very warm days, the telegraph ceases to act about 10 oclock, and continues in an unfavourable condition until towards evening. What is the cause of this phenomenon. Is it due to electricity evolved by the heating of the wire, or by the increase of vapour in the atmosphere, which increases the quantity of electricity. The approximate cause of the action of the telegraph is extraneous currents. [[end page]] [[start page]] 298 [[blank page]]
299 [[end page]] [[start page]] 300
302 [[end page]] 303 May 6th 1862. Smithsonian Inst Experimented on the change which is said to take place in the hardness of iron by magnetization. [[image – apparatus as described]] Placed a rod of iron in a coil through which a current of gavanism from six cells of the large Daniel's battery was transmitted. The iron became strongly magnetic. The point of a steel pin was then brought to bear on the projecting end of the iron rod, and pressed down into the metal by means of a weight suspended from near the end of a lever of the second order. The multiplication of the power was + a half and the weight was 14 pounds, making the pressure equal to 77 pounds. This pressure cause the steel point to sink into the iron, and thus to enable me to compare the results with the iron in the condition of magnetism, and in that of ordinary iron. The difference of the depth of the penetration was inappreciable, and no indication was given from the experiment many times repeated, that Iron is rendered harder by magnetization. This result agrees with that I obtained in an experiment I made last sumer by scratching the pole of the Rhumkoorf apparatus for magnetic polarization with different minerals of the seal of hardness. No difference in the facility of being scratched was observed with or without magnetization. I was induced to make this experiment because I have seen it stated in the journals that the metal is harder when magnetized.
304 Smith Inst May 6th 1862 [[vertical line]] Charged six of the cells of the large Daniel Battery, connected this with the Richie induction apparatus. Connected the [[image – the apparatus described]] two poles of the Inductor with two large pains of glass coated each on one side with tin foil, the two uncoated sides of the plates being placed parallel to each other in an upright position, and the polar wires in contact with the coatings, the two plates attracted each other with a considerable degree of force. The one pane was therefore plus electrified and the other minus. This action was the same as would be produced by charging the two plates with a connection of a Leyden Jar. Directed in De Beust to coat two plates of mica to ascertain what will take place when the current from one pole is split intwo, one part passing through one plate, and the other part through the other, and the second pole connected with the gas pipe of the building, Richie apparatus. [[image – second apparatus]] Light from large pane of glass coated on one side, iron filings on the other, beautiful [[corrus catrons?]]. When the poles were at the distance of about 15 inches, the appearance was that of a ramified spark around each pole with long spark between. When the poles were near together the [[image – sparks]] sparks were eliptical as if mutually repelled. [[end page]] [[start page]] Smith Inst 305 May 7th 1862 Experimented again with six cups of Daniel's batter. Sent spark between two poles of tin foil, one soon began to burn and gradually converted two inches of the narrow strip of metal into an oxide. Same effect produced by the termination of the two poles by two pieces of very fine iron wire. The negative poles took fire and burned with a small but very brilliant bead. In all cases, one pole appears to have greater heating power than the other. [[image – apparatus]] Prepared two guarded points of platinum wire in glass tubes When these were plunged into a vase of water, and the spark made to pass, a light of an intensely red colour was seen at one pole. The spark in alcohol was much brighter than in water, and attended with a loud snap. [[image – apparatus]] When the electrodes were farther separated the ^[[spark]] was divided as in the case of the coated pane covered with iron filings. This is somewhat [[strikethrough]] [[?]] [[/strikethrough]] [[image – apparatus]] When the electrodes were separated to the distance of one inch, a rapid decomposition of the alcohol appeared to take place with the evolution of gas from one pole, which descended to the bottom of the jar, and gas from the other which asscended. The gas which descend at the one pole rose at the other, and after working the machine a short time, the whole of the ^[[liquid in the]] vessel above the points was rendered cloudy.
306 Smith. Inston. May 7th 1862 [[image – apparatus]] By placing a card between the two terminals, combustion of the card was produced. The burning in both cases taking place at the same end as that from which the heavy gas descended. The same terminal deflagrated the fine iron wire, therefore this is the negative pole. In the experiment with the card, the penetration take place at the negative pole – the same as in the case of heating. This is an old fact inregard to ordinary electricity in which the penetration of a card always takes place nearer the negative pole in atmospheric air, but in the middle in a vacuum. [[underline]] All these facts are connected. [[/underline]] [[image – apparatus]] When the gas flame was placed between the two poles, the flame was very much agitated, when exposed to one pole, and only received a tremulous motion, when the polarity was changed, The one pole and then the other being connected with the gas pipe. [[image – apparatus]] [[underline]] Motion in Mercury and solution of protosulfate of iron. [[/underline]] A flat globule of mercury was placed in a capsule of porcelain, and over this a quantity of protosulphate of iron was poured. When one pole was [[end page]] [[start page]] Smith Inston 307 May 7th 1862 placed at the + point, and the other at the -, a remarkable motion was observed in the liquid, which was rendered very strikingly visible by a fine dust of burn paper, scraped from the edge of a burnt card. The motion consisted of two currents produced by an action of repulsion from the pole, and a mutual action at the other. When the mercury was removed, the [[image – diagram]] action ceased, although the poles of the battery were not in contact with the liquid metal. I think these motion are connected with the change in the elastic force of the external filament of the liquid, or in other that they are due to surface action modify by the galvanic decomposition. [[horizontal line]] May 8th 1862 [[image – diagram]] Repeated the last experiment of yesterday with the same arrangement, excepting the mercury which was replaced by a disc of copper of the same size. With this arrangement, no motion was observed. When the coper was removed, and its place supplied with mercury, the motion tooke place with considerable rapidity. N.B. The motion of the current was in all these experiments from the negative towards the plus pole. [[short horizontal line]] The arrangement being the same as in the last experiments, a powerful magnet
308 [[underline]] May 8th 1862. [[/underline]] was placed under the capsule containing the mercury, but no change was produced in the direction or velocity of the current, whether in one direction as regarded the magnet, or another wither transverse or longitudinal with reference to the line joining the polarity. [[short horizontal line]] From this fact, it would appear that the current is not due immediately to the galvanic current, since in that case it would have been affected by the magnet. [[short horizontal line]] Tried the same experiment with a solution of Ferocyanide of potassa, but no motion was produced. [[short horizontal line]] [[image – apparatus]] arranged two test tubes in a glass vessel with two guarded poles. gas was given off at each pole, when the apparatus was plunged into alcohol, and the test tubes filled with the same liquid. The gas asscended into the tubes in small quantities, although quite a commotion was produced at the ends of the poles, but this probably produced by the steam or vapours of the alcohol, since most of the minute bubbles disappeared before they reached the upper [[end page]] [[start page]] 309 May 8th 1862 part of the tubes. In this form of the experiment the gas or mistings from one of the poles, did not fall down towars the bottom of the vessel as in the arrangement of expermt of yesterday. The tubes appeared to prevent this effect. When the condenser was detached from the Rhumkorff the decomposition ceased and was renewed immediately when the screw making the connection was turned down. The two gases having been collected, were tested the were found to be in each test tube hydrogen. The decomposition was probably that of the alcohol into hydrogen and carbonic acid gas, the latter was the substance which was disolved in the liquid, and which was caught in the tube which contained the less amount of gas. [[image – apparatus]] The one tube was filled with gas, the other about 2 thirds filled. The carbonic acid was given off from the negative pole; or from the one which set fire to a piece of paper. The fact that hydrogen was found in both tubes, would appear to indicate that the current from the Inductive apparatus is osscillatory. [[horizontal line]] [[image – diagram]] Made copper wheel revolve in contact with mercury, while a current from six cells of large Daniels Battery was passed from the pereffery to the axis of the wheel. I thought
310 May 8th 1862 May 12th that some retardation in the motion of the wheel might possibly be exhibited when the galvanic current was passed from the periffery of the wheel to its axis, but with the arrangement here employed no effect of this kind was observed. I shall however repeat the experiment under more satisfactory conditions. I do not feel certain however, that such an effect as I have mentioned ought to be expected, so long as there is no external reaction, or as it were nothing against which the polarity of the line of particles forming one of the radii of the wheel can act. The motion of the wheel would only bring a new portion of the metalic periphery into contact with the mercury, and thus increase the length of the current. I find in looking back in this book, that I tried the foregoing experiment at Princeton on the 3rd of May 1843, nineteen years ago. I have alwas intended to repeat it under more favourable conditions. [[short horizontal line]] What an annihilation of time is produced by taking up a set of old investigations at the point at which they were left may years before. The intervening impressions on the memory are excluded, and the present and long past are in juxtaposition. [[short horizontal line]] May 12th Monday 1862 [[vertical line]] 12 elements as 2 series [[vertical line]] [[image – diagram]] Tried the experiment on the opposite or rather last page, with a more delicate arrangement. For this purpose, the magneto electric apparatus with train of wheels inverted with the copper wheel dipping into a a trouch or gutter of mercury. In this arran, [[end page]] [[start page]] May 12th 1862 311 the current of the battery had very marked effect when the weight which gave motion to the copper wheel was loaded, so that the wheel would revolve with a rapidity which of ten times in a second it would be brought to rest in the course of half a minute by applying the current. There can be no doubt as to the reality of the fact of the stoppage of the wheel. It may be produced by the direct action of the current, or by an increased friction produced by the effect of the current on the pivotes of the apparatus. After the wheel was stopped by the application of the power to the battery, it did not immediately start into motion, when the current was interrupted, as it did when the motion was stopped by hand. This was often repeated and always with the same result. It appeared that when the whele after having been stopped by the currant was moved around in the mercury about a quadrant. But we shall try this experiment with a still more convenient apparatus. In this the electricity passed from pivot hole to the pivot, and may have produced an effect on the oil.
312 May 12th. 1862 [[wavy vertical line]] [[image – apparatus]] Repeated the experiment as to the hardness of the bar of iron after magnetising, but found the same result as before, without or with magnetism, the indentation produced by the steel point [[underline]] a [[/underline]] was the same. The fact is not true that magnetization increases the hardness of the bar. [[horizontal line]] [[image – diagram]] Repeated motion on mercury, globule or rather disk on flat dish covered with water, motion observed when the water from the penstock which contains some iron was three fourths of an inch disk but irregular— Next placed over the mercury strong sulphuric acid, motion excidely rocked for a short time, when the mercury was covered over with a thick coating of an oxide. This coating gradually was disolved, and the mercury began to reassume its original brilliant surface. The scale was then washed off, and the acid replaced with water, in which as before, a rapid motion took place. It appeared a little accelerated by a small quantity of a solution of sulphate of Iron. [[end page]] [[start page]] 313 May 12th 1862 I have said that when the water was 3/4 of an inch above the surface of the mercury, the motion at the surface was irregular, this was produced I think, by the seat of the action being at the surface of the mercury, and thus given rise to motion in vertical planes, or variously inclined and more diversified in this inclination, as the liquid over the mercury is deeper. To ascertain whether the hypothesis is correct which I have advanced above as to the seat of the motion being at the surface of the mercury, I placed a ^[[round]] disk of glass over the mercury, and in contact with its surface. With this arrangement, all motion ceased in the liquid, although in some cases when the glass was slightly detached from the mercury, motions were observed in the [[?]] or middle space. [[vertical line]] In these experiments on Motion, 12 elements of the larger Daniell's battery were used in one series. The cause of the motion appears to me is due to the diminution of the cohesive tenacity [[strikethrough]] of the [[/strikethrough]] of the superficial film of water in contact with the mercury, this causes a disturbance of the equilibrium , as in the ccase of the bursting of a soap buble. The thin film very energetically contracts on itself, and gives rise to a rapid motion—. Try the effect [image – scale]] of [[detatching?]] a disk while current is passing.
314 [[wavy vertical line]] May 13th 1862 [[wavy vertical line]] When the experiment of the revolving wheel was repeated this afternoon, with a much more delicate movement in which the current passed to the wheel through mercury and not through the pivots of the machine, no effect was produced. I could not see the slightest effect. [[ horizontal line]] The stoppage in the experiements of yesterday was therefore due to the increased friction, and not to any reaction from the current. Next attempted to observe the effect the stoppage of the wheel by means of the magnetic reaction, but did not succeed in producing much effect with this arrangement, in which the jaws of the Foucault apparatus was placed on each side of the wheel, or in other words ^[[when]] the wheel was placed [[strikethrough]] on the [[/strikethrough]] between the two jaws of the apparatus. The two actions in fact are antagonistic to each other, the magnetic induction tends to stop the wheel, while the electro-magnetic action tends to give it motion. [[end page]] [[start page]] May 14th 1862 [[wavy vertical line]] 315 [[image – diagram]] Poured into a flat dish a flat disk [[strikethrough]] h [[/strikethrough]] of mercury an inch and a half in diameter, and over this placed an amalgamated disk of copper [[strikethrough]] When [[/strikethrough]] ^ [[of]] two inches 5/8 in diameter. When the current from twelve Daniell's cells was sent through a solution of sulfate of iron, one pole being in contact with the pole, and the other in the liquid, rapid motion was exhibited as shown in the diagram, but when the amalgamated place was put on top of the mercury, no motion was produced although the surface of the copper was covered with mercury. This with the want of motion, with the place of thin glass interposed, indicated that a liquid surface of mercury is requisite to produce motion. To illustrate this still farther, a quantity of mercury was poured over the copper, – with this rapid motion was produced in [[strikethrough]] a [[/strikethrough]] wide circuits. While this motion was produced in the solution, none was apparent in the mercury. A number of minute bubles on the surface of the metal was entirely stationary, while the liquid solution above was in rapid movement.
316 May 15th 1862 Wednesday evening [[image - apparatus]] Tried a small portable galvanometer made by [[?]] Dr Baust from a description of one in the Phil Magn for 1860 or there abouts, by I think Joule. It performed very well,— with a single drop of sulphuric acid ^[[in a wine glass of water,]] the longer needle moved through 30° when the ends of the two wires were dipped into the liquid. Made experiments on the current from different pieces of iron, one hammered the other soft. found little difference in effect. Put in operation the short wire double galvanometer of Rhumkorff with an astatic needle. With this, a current permanent in character was found to exist between the gas and the water pipes of the city, the water pipe being constantly plus or giving off the current, while the gas pipe is negative. The water pipe is therefor being acted upon by the liquid, and rusting more rapidly on account of its association with the gas pipe through moist earth and any [[strikethrough]] and [[/strikethrough]] metalic contact. The greater action is on the water pipes perhaps on account of the lead pipe with which it is associated. Tried the electromotive character of different metals. The following are the results + Iron and-platinum + Iron + -Lead +Iron +-copper +Iron + -Tin +copper + -Brass -Lead +Tin [[note at left]] A single droop of sul acid in wine glass of water [[end page]] May 15th 1862 Thursday even. [[wavy vertical line]] Experiments on the direction of the current in different galvance arrangements 317 Repeated last experiment with a drop of nitric acid, instead of sulfphuric acid. { Iron platinum} stron + - {Iron — Tin} very feeble + - nitric + water {Iron – Lead} stronger + - {One drop of acid in two ounces of water {Lead – Tin} feeble - + {Brass — copper} Feeble + - {Brass — copper} stronger + - {acid increased to thre drops [[overlay]] Holes in paper by the electric discharge . . . . . . poles . . . . . . poles 50 60 70 80 85 90 one jar [[/overlay]] Two drops of acid in wine glass of water about 2 ounces The steel was not hardened It was the end or handle part of a flat file. [[Horizontal line]] nitric copper copper amalgamated no current acid o o sul copper amalgamated copper feeble acid + + sul Tin amalgamated copper } powerful acid + - nit } mercury copper very feeble acid - + When two wires of iron were made the poles, and plunged into a very dilute mixture of sul acid, the needle indicated a motion first on one side then the other. The slighest physical difference appeared to change the direction of the current, one wire being a little warmer than the other, rendered it +, a little more oxidated rendered it minus.
May 15th 1862 Thursday even. May 15th 1862 Thursday even. [[wavy vertical line]] Experiments on the direction of the current in different galvance arrangements 317 Repeated last experiment with a drop of nitric acid, instead of sulfphuric acid. { Iron platinum} stron + - {Iron — Tin} very feeble + - nitric + water {Iron – Lead} stronger + - {One drop of acid in two ounces of water {Lead – Tin} feeble - + {Brass — copper} Feeble + - {Brass — copper} stronger + - {acid increased to three drops sul brass copper acid + - water tin lead + - Two drops of acid in wine glass of water about 2 ounces sul iron steel acid - + nitr iron steel stronger acid - + The steel was not hardened It was the end or handle part of a flat file. [[Horizontal line]] nitric copper copper amalgamated no current acid o o sul copper amalgamated copper feeble acid + + sul Tin amalgamated copper } powerful acid + - nit } mercury copper very feeble acid - + When two wires of iron were made the poles, and plunged into a very dilute mixture of sul acid, the needle indicated a motion first on one side then the other. The slighest physical difference appeared to change the direction of the current, one wire being a little warmer than the other, rendered it +, a little more oxidated rendered it minus.
318 May 20th 1862 For experimenting on surface action, I find a clean fich surface of mica the best, on this water will spread and adhere. If a quantity of the liquid be formed on a plate of clean fish surface of mica placed horizontally so as to heap it up around the edges, and indeed over the whole plate, and then a drop of strong alcohol be let fall on the middle of the plate, which may be round, the water will be drawn off in a circular space heaped up at the circumference of the space, with various motions, all from the same cause, namely the change of capillarity of the liquid for the solid. [[image of a scale]] Placed plate of glass on surface of mercury, passed galvanic current through the metal, but did not find any diminution of the cohesive force. [[short line]] Next placed over the mercury a stratum of water acidulated with a few drops of sulphuric acid. The same experiment was repeated, but no effect on the capilarity of the water and the glass was observed. The glass in this case was elevated perhaps a length of an inch above this [[end page]] [[start page]] 319 surface of the surrounding liquid, and between the glass and the mercury a rapid motion of the particles was observed in vertical planes. [[image]] The motion was in the space filled with the undulated water between the two surfaces, that of the lower side of the glass plate and the upper side of the mercury. The motions was in the acid over the mercury was best seen by grating with a somewhat corse file a quantity of filings of cork. These when viewed from above, reflected in the mirror surface of the mercury, appeared like a [[?]] of short columns revolving with main rapidity around two centres near the plus pole plunged in the acid the negative being in the mercury. To show more conclusively than before that the motion is due to the surface action of the battery, a very thin fillm of mica was placed on the surface of the mercury under the stratum of acid, but no motion was observed when the current was passed through the liquid, or through the mercury. The surface after the current was passed for a time became covered with a film or oxide, which is gradually disolved.
320 May 20th 1862 [[image]] The large induction apparatus constructed by Richie is made in two parts which may be separated, forming a coil of half the length on the stand, and the other half of the coil to be used as a inducing coil for a tertiary current. When a current was sent through the instrum from the acid an induced current through the second part of the long coil, a shock was received, but not very intense from the ring coil held above; but when the induced long coil was [[image]] placed upon a flat coil, no effect was produced, the induction was not sufficient intense to force the current through so long a wire. [[short line]] [[image]] Attached a jar to the larger induction apparatus at each breaking of contact; very loud short discharge was produced. When a card was placed between the poles a b, a single perforation was made [[end page]] [[start page]] 321 with a burn on each side, apparently larger on one side than the other. The fact of the singleness of the perforation was important, as it tends proove that the spark consists principally of a single discharge. This is probably not the case when two half coated pains of glass is charged for a moment. Try this. [[image]] When the spark from the great induction apparatus passed through a card, a single hole was made, except when the spark itself was divided into two branches. A singular phenomenon was observed [[image]] which exhibits the fact of the penetrating power of the spark is greater than for a [[word circled]] sheet [[/word circled]] of paper, even when the latter is thoroughly wet. (Place in the same position a piece of tin foil, see what will be the result.) In the arrangement of the jar on the opposite page, the noise of the spark was very intense, and being so uncompounded and sharp, it gave a very distinct echo in the laboratory when ordinary sounds would produce no effect of the kind. This snap would do good service in experiments on sound. [[image]] This experiment is a remarkable one, why should the discharge take place through so great a distance around in preference to going through a good conductor shuch as a : a piece of wet paper?
322 June 17th 1862 When a small drop of water is let fall into an oil, or other liquid of the same specific gravity as the water, it does not spring into vapour, even when the temperature is elevated to 40° or 50° degrees above the boiling point. This is a fact. [[line under this sentence]] June 19th The question occurred in the club as to the state of carbon in the form of dust deposited from gas to a plate of glass, whether it was transparent, or whether the light passed through between the deposit of particles. If it were transparent by transmission of light, it might possibly depolarize light. Tried the experiment, but could not see the least indication of of depolarization, when a piece of smoked glass was placed between the deploarizing [[circled]]primers[[/circled]]. The thinnest film of mica produced under the same condition a very striking effect. [[line across page]] [[image of stepped block to left of following paragraph]] Magnetized two needles (no 2) to saturation with the large magnet, each gave the same degree, near 40 on the magnetometer. Magnetised an other needles (no 2) with the large magnet magnetic force a little more [[underlined]] than 40°-.[[/underlined]] Magnetized the same needle in a spireal of single spires in the circuit of the battery with six amps, the needle was magnetized to the same degree which is that of saturation. Attempted the magnetize, the same needle by means of the spark from the Rhumkorff but little effect. [[end page]] [[start page]] June 17th, 1862 323 Made a spiral with three layers of spires, with this not sufficient magentisim was produced with the induction apparatus, and the circuit closed to affect the magnetometer. [[images of a coil one below the other/line halfway across page]] When the spark from the induction apparatus was interrupted the needle was [[strikethrough un [strikethrough]] by the nature[[[/strikethrough]] to an intensity of 15°. These results are in accordance with what I might have anticipated, the needle in the first experiment given above was magnetized by the first current and unmagnetized by second. In the second experiment, the needle was magnetized by the first current, and not unmagentized by the second, because it had not sufficient power to force its way through the air. [[short line]] [[image of paper with + and - line through it]] When a piece of tin foil was placed in a opening in a card, or rather thin paper, and the foil placed near the negative pole, the spark appeared to pass directly through the foil, but when the tin foil was placed near the + pole, the spark issued from the edges of the foil, as if it were charged and gave off its electricity from its most salient points. [[ image to left of this paragraph, similar to above]] These results are in accordance with the facts that the plus discharge more readily penetates the air than the minus one.
324 Nov 18th 1863 Commenced experimenting on different kinds of oil in continuation of the experiments made at Boston in September. [[image of cup]] Copper cup containing about a pint of water. In the bottom of this a hole was made of about 1/10 of an inch in diameter,through which 6 oz of water was suffered to discharge itself. The times of flowing were as follows. Water 87 Secds. Alcohol 81 1/2, Lard oil 148. Sperm oil 109 1/2. These were samples of old oils [[short line]] Second series samples of old oils Water 93 Secds Lard oil Sperm oil " 94 Secds 171 seconds 116 secds 172 seconds 115 secds Kerosene oil 85 " " 85 The above are preliminary experiments, the same relative times are exhibited, but the absolute differences is considerable. [[short line]] Observed the fact that as the oil passed downward in an untrouble stream like a glass rod plunged at one end into a vessel of water, bubbles of air were carried with it, indicating an adhesion of the particles of air to the oil. The attraction for kerosene oil was much less. [[end page]] [[start page]] Nov 18th 1863 325 Observed on Saturday when visiting the Treasury Department, the effect of pressure in developing electricity a sheet of Indian rubber became so highly electrical when submitted to the pressure of an emense hydrostatic press, as to cause a sheet of paper to adhere with considerable tenacity. Make farther observations on this phenomenon, which has been studied on a minute scale by Becquerrel.
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[[start page]] 552 [[image-similar to greater than sign]] The magnetism of a long bar in the direction of its length is readily explained on the principles of polarity, and the action of a whole series of particles from one end of a bar to the other. A series of small magnetic needles arranged transverse to a long bar would be [[Fig. 1 in margin - image of small needles in 3 rows]] in a state of unstable equilibrium, and the slightest jar would be sufficient to overturn it, so that the needles would take the position shown in the 2nd figure. [[Fig. 2 in margin - image of 3 rows of small needles, all parallel]]. [[end page]] [[start page]] 553 [[underlined]] Explanation of currents in iron [[/underlined]] [[2 images - bar with magnetic fields]] These sketches will serve to give an idea of the [[strikeout]] circles [[/strikeout]] currents of electricity flowing from one end of an atom to another. When the whole atom is surrounded with currents flowing in lines [[note: pages in the way, continuing below them]]It may be of mere vibration of parts, as in the case of the luminosity of the diamond after being exposed to the light o the sun. Also when a piece of Iceland spar is heated, it becomes luminous before the surrounding medium.
I recalled [[? or maybe a name like niccollet?]] May I ask the favour
[[image - concentric circles]] The increase of metal does not, after a given amount, increase the strength. [[image - line]] In stretching copper or iron wire, a set takes place before breaking (Hosford). [[image]] What effect has the vibration of a larger gun on the progable [[?]]. Lead does not increase in density by hammering. Does vibration crystalyze iron? Query [[?]] iron wire by magnetism, put it in diluted sol [[?]], and see if the fibres are destroyed. The plates of the Target rendered crystaline by a single blow of a ball
[[start page]] Does a string loose its elasticity by longness? Do the unneeded glass loose its depolarizing property by long time? [[end page]]
[[image - doodles]]
552 The magnetism of a long bar in the direction of its length is readily explained on the principles of polarity, and the action of a whole series of particles from one end of a bar to the other [[image with Fig 1 written in left margin next to it]] A series of small magnetic needles arranged transvers to a long bar would be in a state of unstable equilibrium, and the slightest jar would be sufficient to overturn it, so that the needles would take the position shown in the 2nd figure. [[image with Fig 2 written in left margin next to it]] [[end page]] [[start page]] 553 [[underline]] Explanation of current in iron [[/underline]] [[image]] These sketches will serve to give an idea of the [[strikeout]]circles[[/strikeout]] currents of electricity flowing from one end of an atom to another. When the whole atom is surrounded with currents flowing [[strikeout]]like[[/strikeout]] in lines like the meridians of a globe from end to end of the atom, or from pole to pole, then the atom is neutral to any exterior action, the currents neutralize each other, but when a magnet, or a current is brought externally over an atom, then the currents in the atom are all drawn on one side, as the meridians of a globe would be, were they made of movable wires, and current passed through them, while another strong current was passing parallel to them along one side. [[image]] The fact of the heating of one pole of a galvanic battery first can be readily explained on the principles of a current of heat taking place in one direction, while a current of galvanism is transmitted in the other. also the experiment of Peltier of producing cold by means of a current of galvanism. [[image]] In all cases of fosphorescence, it would appear that some molecular change is going on, perhaps not a permanent one, it may be of mere vibration of parts, as in the case of the luminosity of the diamond after being exposed to the light of the sun. Also when a piece of Iceland spar is heated it becomes luminous before the surrounding medium.
554 Make experiments on the velocity of the diffusn of gas in air.- Close the two enterances of one of the upper halls in the old college, then liberate a quantity of sulphuratted hydrogen at one extremity of the gallery, and with a stop watch, note the moment of the arrival of the smell at the other extremity. Perhaps the sense may be assisted by placing a smelling trumpet in the nostril. Use Mrs H's accute sense in these exp. Note the barometer, Thermometer, & the Hygrometer. M. Masson has studied with care the intensity of the electrical light under different circumstances of development, by using a revolving disc which makes 300 turns in a [[strikeout]] minute [[/strikeout]] second. He sais that he has been induced by his experiments to admit that the electrical light is a simple explosion in the fluid ether, which it puts in movement, and to believe that the [[word circled]] transportation [[/word circled} of the metal by the spark is not the cause of the light, ^ [[but]] that it augments it in [[strikeout]] increasing the [[/strikeout]] causing an increase in the conductability of the circuit. We think besides (sais he), that the electrical spark acts in the combination, and decomposition of substances chemically operates in two manners, 1st as a current of electricity, in this case it decomposes; - 2ndly as a heated body in ignition, in consequence of the incandescence of ponderable matter in the act of transportation, and then it produces combinations. Compt Rendus, 19th July 1844. [[image]] A simple constant battery, fill an old brass kettle with earth, saturated with a solution of sal ammoniac, plunge into this a cylinder of zinc, and the apparatus is complete. The pile will continue in action for months, by occasionally renewing the sal ammoniac. The zinc should first be dipped into a strong solution of ammoniac, so as to incrust it with the salt. Bib Geneva 1844 [[end page]] [[start page]] 555 According to Mr Grove, all physical phenomena maybe refered to matter and motion. We may talk of light or heat or magnetism or electricity, but they may be conceived as only modes of motion, and their existence is principally known to us by the effects of motion associated with matter.
556 M Haldal finds that no modification in the conductor as to density etc, except a diminution of intensity influences the current. Also the effect of aggregation is one to warrent of continue. The magnetism of the conductor has no effect. See annalus december, vol 8. 1843. Lord Mahon found them when a fine wire was coated with bees wax, leaving a portion uncoated, he found that the uncoated part was melted,while the coated part was not. The explanation given by necessity is simple,- the wax in a solid state is a non conductor, the discharge heats the wax, renders it a conductor, and hence the wire is preserved. From this, it would appear that the discharge occupies some time, and is of a considerable length, as indeed is shown by the experiment of Mr Wheatstone. Oil made by distilling sperm oil at a high temperature, possess great diffusive power. a drop put on the hand extends up the arm. Make experiments on this, in connection with surface action. For an account of two holes made in a tin plate of a house struck by lightning, see Brands [[?]] Vol 12, p 414. Two holes were made in a tin plat against the chimney, the holes were about an inch in diameter, and 4 inches apart. Each hole was strongly burned, but the persistent fact was that the burrs were on different sides in the tin holes. The burrs are due to the repulsion of the water at the moment of the passage of electricity, and the [[word circled]] prohiberance [[/word circled]] will be on the side of least pressure. J.H. [[end page]] [[start page]] 557 Facts for consideration Prof Morr informs me that he has repeated the exp of the suspension of a rod of iron in the center of a coil, through which a galvanic current was passing. The wire was of the size of that used for bills, and 300 feet long, with a battery of 3 or 4 elements. The rod was about 5 or 6 inches long, 1/4 of an inch in diameter, and the caliber of the diameter of about an inch. - When the current was broken, the rod was thrown out. - exam this phenomenon. For a simpler machine for winding wire, see Oschaunnnesys book. Also for the following facts. When a current of galvanism is passed through a long wire, the metal is thrown into a wavey agitation at the moment of interrupting the current. De La Rem finds that a battery of a single element with peroxide of lead, instead of nitric acid, is more powerful than one with nitric acid, although a number of [[?]] is less so. This effect is probably due to the intensity ending the elect, to decompose more [[?]] the nitric acid, also the same in the case of Daniells battery. He finds that the adhesion of the hydrogen is a cause of the deteorration of the battery. Proved this by putting the apparatus in vacuum of air pump. The effect of heat in some case may be attributed to this. see Annales de Chime, vol 8, 1843. In a conversation this afternoon with Dr. Torry, the question occurs how do the plants in deep water grow with so little light? May not the chemical ray be more penitrating to water than the light rays. April 29, 1847
558 US' Steamer, Beaufort, was truck with Lightning at Cumberland [[circled]] [[Ismith?]] [[/circled]] Georgia, while on Survey 1843. The lighting struck the mast on which a square sale might be hoisted, the vessel was at anchor. The shock was so sever as to knock down two negrows, and to affect several other persons. The two knocked down were 5 or 6 feet off. The top of the mast was black for about 10 feet, this part was unscathed; when the discharg[[strikeout]]ed[[/strikeout]] reached the white paint below, the mast was split nearly down to the deck, a seam or groove was made down the mast, and [[word circled]] groove [[/word circled]] followed the mast down into the hold as far as the level of the water without. The groove terminated at the waterline without per mark. One of the officers of the vessel remarked that he had leared that the lightning never went below the water line in a ship. This appears to be probable. [[image]] Let [[underline]] a [[/underline]] [[underline]] b [[/underline]] be the water, a strong induction action would take place in the edge of water which would draw the electricity from the mast. [[underline]] Lieut. Smith [[/underline]]. Reported by Cap. Mackey of the Top Engineers. [[end page]] [[start page]] 559 [[end page]]
560 [[end page]] [[start page]] 561 Lesley recommends flannel [[word circled]] dried [[word circled]] before a fire, cooled between pulcer [[?]], and put under a bill glass as a good drying substance, answers instead of sulphuric acid.
562 Annaversary of Phil Society p 51. Electricity from molecular disturbance p 69. Direction of induced current 76, Italian Method 77,78,79 81 82 83 84 85 86 87 88. Latteral induction p 55 56 57 58 59 60 61 62 63 64 65 66. Ordinary induction p 60. [[end page]] [[start page]] Index 563 Constitution of matter capillarity - p 1234.12 13. Conduction of bodies for elect on the surface or in the interior p54 6266. Earth + water compared p71. Curious experiment on elect light p 45. Deguereotype 37 38 41 42 47. Illumination by elect light 59. Induction at a distance p6 7 13 58 p70.71.72 73 74 75 76 78 79. p Light p65. Lighting. Quinby's obs 14 needles magnetized 36-37 gutter struck. Magnetism dip p9 animal magnetism 19 moon light 48. Pasivity of iron 24. Phosphorogenic emanation p 15 16 17 18 p 34 35 36 42 43 46 47 48 49 50 52 under water 54. Polarization of light 25. of a conductor 33 of Phos Emanation 34. Projectiles machine for 10 11. [[end page]]
564 Thermo elect apparatus - Millom p27 evaporization of water produced persuant deflection, p28 cold 28 tin foil in mercury 28 exp p68 Temperature from magnetisation p29 31{ temperature by capillary 31 p32 33 from India rubber streached p69 Thermo telescope p30 53 alum [[word circled]] athermal [[/word circled]] p45 Rain under trees p66 Vilocity of elect plan for getting p69 Water shock through p67 Wave of electricity p80 [[end page]] [[start page]] 565
566 [[end page]] [[start page]] 567
568 [[end page]] [[start page]] 569
570 Hacketts experiment of the adhesions of a plate of metal may be exhibited with [[image]] a stream of water - See [[underlined]] Annale de [[/underlined]] chemie vol 35 1827 p 34 36 p 69. Quarterly Jour 1827 vol 1 p 472, vol 2 p 193, Young Nat Phil vol 1 pages 298 778, R Willis in cambridge transactions vol 3 part 1st p [[insert]] ^ 129 to [[/insert]] 140. For a paper on the nature of the ethereal medium to which is referred this action of light, Phil Transactions vol 7, part 1, pages 111. p 97 Each particle of the ether exerts two forces, one attractive and varying reciprocally as the square of the distance, and the other repulsive and varying inversely as a higher power than the square of the distance. R. A. [[circled]] Tilghman [[/circled]] informs me that by [[circled]] grounding [[/circled]] flint to an unpalpable power with pure water, it will cohere into a solid mass, but if the smallest quantity of salt be added, this effect does not take place. [[end page]] [[start page]] [[blank page, interior of back cover]]
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