Joseph Henry

Joseph Henry
Birthday	Sunday, December 17, 1797
Birthplace	Albany, New York, USA
Died	Monday, May 13, 1878
Nationality	United States
Known for	Electromagnetic induction, Inventor of a precursor to the electric doorbell and electric relay

Henry, Joseph

(1797–1898) physicist; born in Albany, N.Y. He worked as a tutor, then as a surveyor (1825–26) before becoming a professor at his alma mater, Albany Academy (1826–32). He began research on electromagnetism (1827), constructed the first electromagnetic motor (1829), and discovered electrical induction independent of English physicist Michael Faraday. The "henry" unit of inductance is named after him. He continued his research after transferring to Princeton (1832–46), demonstrating the oscillatory nature of electrical discharges (1842), and diversifying into the fields of astronomy, galvanometry, and telegraphy. In 1846 he was named first secretary and director of the Smithsonian Institution; through his leadership (1846–77), the Smithsonian supported internationally cooperative scientific research. While administrative duties left him little time for the "pure" scientific endeavors he favored, Henry introduced a system of weather forecasting, investigated the propagation of light and sound waves by lighthouses, and encouraged the museum's patronage of anthropology and ethnology.

The Cambridge Dictionary of American Biography, by John S. Bowman. Copyright © Cambridge University Press 1995. Reproduced with permission.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Henry, Joseph

 

Born Dec. 17, 1797, in Albany, N. Y.; died May 13, 1878, in Washington, D. C. American physicist.

In 1832, Henry was appointed a professor at the College of New Jersey (now Princeton University). From 1846 he served as secretary and director of the Smithsonian Institution. In 1868 he was appointed president of the National Academy of Sciences, and in 1871 he became the first president of the Philosophical Society of Washington. His principal works were devoted to electrical engineering. In 1828, Henry built the first high-powered electromagnets using multilayered coils of insulated wire. He discovered the phenomenon of self-induction (1832) and the oscillatory character of the capacitor discharge (1842). The unit of inductance in the International System of Units—the henry—has been named after him. Henry also wrote works in meteorology.

WORKS

Scientific Writings, vols. 1-2, Washington, 1886.

REFERENCE

Lebedev, V. I. “Izobretenie Dzhozefa Genri.” Vestnik sviazi, 1946, no. 8.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.