Henry, Joseph (1797-1878), an American physicist, became famous for his discoveries in electromagnetism. He anticipated both Samuel F. B. Morse’s invention of the telegraph and Michael Faraday’s discovery of electromagnetic induction. Henry received no credit for his work at the time, but the unit of electrical inductance is now called the henry (see Henry ).
Henry was born in Albany, New York. He was educated at Albany Academy, where he later taught mathematics and physics. He began experimenting in electromagnetism while teaching there. His first major work was improving the electromagnet, which William Sturgeon had discovered. From 1832 to 1846, Henry was a professor at the College of New Jersey (now Princeton University). He later became the first secretary and director of the Smithsonian Institution. In 1867, he became president of the National Academy of Sciences, which was established in 1863.
