Joseph Henry's Oscillating Electromagnet Motor, by Henry, Joseph 1797-1878, c. 1830s, Smithsonian Archives - History Div, Drawing of Joseph Henry's oscillating electromagnet motor. The motor was a simple device whose moving part was a straight electromagnet rocking on a horizontal axis. Henry, who would later become the first Secretary of the Smithsonian Institution, believed his machine was important as the first demonstration of continuous motion produced by magnetic attraction and repulsion..