1st Secretary of the Smithsonian Institution and famous American scientist
Born in Albany, New York in 1797, he attended The Albany Academy where he excelled at his studies. He was Secretary of the National Institute for the Promotion of Science, a precursor of the Smithsonian Institution, and was the first Secretary of the Smithsonian, serving from 1846-78. The Smithsonian Institution unit of inductance, "The Henry," is named in his honor.
in 1826, Henry was appointed Professor of Mathematics and Natural Philosophy at The Albany Academy where he conducted some of his most important research. His curiosity about terrestrial magnetism led him to experiment with magnetism in general. He was the first to coil insulated wire tightly around an iron core in order to make a more powerful electromagnet, improving on William Sturgeon's electromagnet which used loosely coiled un-insulated wire. Using this technique, he built the strongest electromagnet at the time. He also showed that, when making an electromagnet using just two electrodes attached to a battery, it is best to wind several coils of wire in parallel, but when using a setup with multiple batteries, there should be only one single long coil. The latter made the telegraph feasible. Because of his early experiments in electromagnetism some historians credit Joseph Henry with discoveries pre-dating Faraday and Hertz; however, Henry is not credited due to not publishing his work.
Using his newly developed electromagnetic principle, in 1831, Henry created one of the first machines to use electromagnetism for motion. This was the earliest ancestor of the modern DC motor. It did not make use of rotating motion, but was merely an electromagnet perched on a pole, rocking back and forth. The rocking motion was caused by one of the two leads on both ends of the magnet rocker touching one of the two battery cells, causing a polarity change, and rocking the opposite direction until the other two leads hit the other battery. This apparatus allowed Henry to recognize the property of self inductance. British scientist Michael Faraday also recognized this property around the same time. Since Faraday published his results first, he became the officially recognized discoverer of the phenomenon.
From 1832-46, he served as the first Chair of Natural History at the College of New Jersey, now Princeton University. While at Princeton, he taught a wide range of courses including natural history, chemistry, and architecture, and ran a laboratory on campus. Decades later, Henry wrote that he made "several thousand original investigations on electricity, magnetism, and electro-magnetism" while a member of the Princeton faculty.
Professor Henry was introduced to Professor Thaddeus Lowe, a balloonist from New Hampshire who had taken interest in the phenomenon of lighter-than-air gases, and exploits into meteorology, in particular, the high winds which we call the jet stream today. It was Lowe's intent to make a transatlantic crossing by utilizing an enormous gas inflated aerostat. Henry took a great interest in Lowe's endeavors, promoting him among some of the more prominent scientists and institutions of the day.
In June 1860, Lowe had made a successful test flight with his gigantic balloon, first named the "City of New York" and later renamed "The Great Western," flying from Philadelphia to Medford, New York. Professor Lowe would not be able to attempt a transatlantic flight until late spring of 1861, so Henry convinced him to take his balloon to a place further west and then fly the balloon back to the eastern seaboard, an exercise that would keep his investors interested.
Lowe took several smaller balloons to Cincinnati, Ohio in March 1861. On April 19th, he launched a fateful flight that landed him in Confederate, South Carolina. With the Southern States seceding from the Union, during the winter and spring of 1860-61, and the start of the Civil War, Lowe abandoned further attempts at a trans-Atlantic crossing and, with Henry's endorsement, went to Washington, D.C. to offer his services as an aeronaut to President Lincoln and the Federal government. Henry submitted a letter to Simon Cameron, U.S. Secretary of War at the time, which carried his endorsement. On Henry's recommendation Thaddeus Lowe went on to form the United States Army, "Balloon Corps" and served two years with the Army of the Potomac as a Civil War "Aeronaut."
As a famous scientist and director of the Smithsonian Institution, Henry received visits from other scientists and inventors who sought his advice. Henry was patient, kindly, and self-controlled. One such visitor was Alexander Graham Bell, who on March 1, 1875 carried a letter of introduction to Professor Henry. Henry showed an interest in seeing Bell's experimental apparatus, and Bell returned the following day. After the demonstration, Bell mentioned his untested theory on how to transmit human speech electrically by means of a "harp apparatus" which would have several steel reeds tuned to different frequencies to cover the voice spectrum. Henry said Bell had "the germ of a great invention." Henry advised Bell not to publish his ideas until he had perfected the invention. When Bell objected that he lacked the necessary knowledge, Henry firmly advised: "Get it!"
On June 25, 1876, Bell's experimental telephone, using a different design, was demonstrated at the Centennial Exhibition in Philadelphia where Henry was one of the judges for electrical exhibits. On January 13, 1877, Bell demonstrated his instruments to Henry at the Smithsonian Institution and Henry invited Bell to demonstrate them again that night at the Washington Philosophical Society. Henry praised "the value and astonishing character of Mr. Bell's discovery and invention.
Professor Joseph Henry died on May 13, 1878, and was buried in Oak Hill Cemetery, in the Georgetown section of Washington, D.C. John Phillips Sousa wrote the "Transit of Venus March" for the unveiling of the Joseph Henry statue in front of the Smithsonian Castle.
Bronze statues of Joseph Henry and Isaac Newton represent science on the balustrade of the galleries of the Main Reading Room in the Thomas Jefferson Building of the Library of Congress, on Capitol Hill, in Washington, D.C. They are two of the 16 historical figures depicted in the reading room, each pair representing one of the 8 pillars of civilization.
Signature: 4 1/8 x 1 3/4, in ink, Very respectfully yours, "Joseph Henry," Secy. Smn. Instn. Very desirable American scientist.