[EAS]Joseph Henry

pjk pjk at design.eng.yale.edu
Fri May 30 14:50:34 EDT 2003

Subject:   Joseph Henry

Welcome tribute to an American inventor and scientist, primary
organizer of the National Academy of Science, the American
Association for the Advancement of Science (AAAS) and first head of
the Smithsonian Institution.  --PJK

(from NewsScan Daily, 30 May 2003)

     Today's Honorary Subscriber is the innovative American
scientist Joseph Henry (1797-1878) who has been called the Father of
American Electronics for his work on Electromagnetic Induction, and
is also celebrated for his contributions to American science as the
first head of the Smithsonian Institution. 
     Henry discovered electromagnetic induction -- the process of
converting magnetism into electricity -- a year before Michael
Faraday, but history credits Faraday as the discoverer because he
was the first to publish the phenomenon. Henry was also the first to
develop the electromagnetic telegraph, demonstrating that by using
his electromagnetic relays magnetic action could be transmitted over
long distances.
     Believing that scientific discoveries were for the benefit of
everyone, Henry never patented any of his devices, and credit for
inventing the telegraph went to the non-scientist Samuel F.B. Morse
who only worked on the technical implementation of the device. Henry
was always pleased to see others put his inventions to use, but he
was saddened when his contributions were not acknowledged (as in the
case of Morse). Happily, the scientific community did finally give
him his due by naming the unit of inductive resistance the "henry."
     The son of a day laborer, Henry was born in Albany, New York.
Seeking a career in medicine he studied at the Albany Academy, where
he was appointed professor of mathematics and natural philosophy in
1826. His early research on the relation of electrical currents to
magnetism led to the development of strong electromagnets that used
layers of insulated coils around an iron core. In 1832 he joined the
faculty at the College of New Jersey (now Princeton University),
where he continued the research that led to such discoveries as the
laws for operating electrical transformers and inducing currents at
a distance. In one experiment he magnetized a needle by utilizing a
lightning flash eight miles away, which marked the first use of
radio waves across a distance. By using a thermogalvanometer he
showed that sunspots radiate less heat than the general solar
     In 1846 he became the first head of the newly organized
Smithsonian Institution. There he established a continuing tradition
of original research, resisting pressures to use Smithsonian funds
for a museum, art gallery, and library. Instead he offered aid and
encouragement to scientists engaged in a wide range of enterprises
from western exploration to the building of new astronomical
observatories. He also encouraged the growth of scientific bureaus
in the government and saw the Smithsonian as a clearinghouse for all
manner of scientific endeavors. He helped organize the American
Association for the Advancement of Science (AAAS), serving as its
first president. The U.S. Weather Bureau (later Service) grew out of
a corps of volunteer weather observers that he recruited. As one of
Lincoln's chief technical advisers during the U.S. Civil War, he was
a primary organizer of the National Academy of Science and its
second president.

See http://www.si.edu/archives/ihd/jhp/ for the Joseph Henry Papers
Project of the Smithsonian Institution.

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