Description: As one of the first women to work in scientific illustration at the Smithsonian, Violet Dandridge made her mark at the United States National Museum.
Description: The term “personal equation” came into use in the 19th century as scientists found that observers have inherent biases: some anticipate events, and some report events after they have occurred. Recognition of the problem led to a spate of personal equation instruments: some measured biases of this sort, and some reduced the effect of personal errors. Most of these