# The Cyclopædia of American Biography/De Forest, Lee

DE FOREST, Lee, inventor, b. at Council Bluffs, Ia., 26 Aug., 1873, son of Rev. Henry Swift and Anna Margaret (Robbins) De Forest. His father, a Congregational clergyman, was then located in a pastorate at Council Bluffs, but, in 1879, he removed to Talladega, Ala., where he served as president of Talladega College until 1896. Mr. De Forest's mother was a daughter of Rev. A. B. Robbins, one of the original “Iowa band” of ministers who settled in Iowa territory. He received his early education at Talladega, and prepared for college at Mt. Hermon School, Massachusetts. In 1893 he entered Sheffield Scientific School, Yale University, being graduated in 1896 in mechanical engineering. In college he was an editor of the “Yale Scientific Monthly.” He then took three years of post-graduate work at Yale in physics and mathematics, receiving the degree of doctor of philosophy in 1899. His thesis work was on the subject of “Reflection of Hertzian Waves Along Parallel Wires,” which exhibited the early foundation laid for his work in wireless telegraphy and telephony. In 1898 he enlisted in the original “Yale Battery,” and served with it throughout the Spanish War, but the organization saw no foreign service.
On leaving the university he went to Chicago and secured a position in the Telephone Experimental Laboratory of the Western Electric Company, where he had opportunity to experiment at night upon a new wireless telegraph receiver which he was engaged in perfecting. In 1900 he left that company, and devoted his entire time to developing at Armour Institute the rudiments of what later became the De Forest wireless telegraph system. In New York in 1901 this work was amplified, his first commercial undertaking being to report the International Yacht Races of that summer. In 1902 the American De Forest Wireless Telegraph Company was organized. During this early period (1900-02) Mr. De Forest was first in America to use a self-restoring wireless detector, in place of the Marconi coherer; the telephone receiver, in place of the relay and Morse inker; and the alternating current generator and transformer, in place of the induction coil and interrupter. These radical improvements have since been embodied in every system of wireless telegraph here and abroad, and to them chiefly was due the rapid strides of the new art in the first decade of the new century. The great advantages of the new system were first demonstrated abroad in 1903 in the now historic tests for the British Post Office between Holyhead and Howth, across the Irish Sea. In 1904 the De Forest system achieved world recognition through the spectacular success of the London “Times” war correspondent, Capt. Lionel James, in reporting the naval maneuvers around Port Arthur in the Russian-Japanese War. In the summer of that year the first commercial overland wireless service was opened, between the St. Louis Exposition and Chicago. As the result of this progress the United States navy in 1905 authorized Mr. De Forest to construct for it its first high-powered wireless stations at Colon, Guantanamo, Porto Rico, Key West, and Pensacola. In 1906 Mr. De Forest made public what has since proven his greatest invention and one which has since made possible transcontinental telephony, by wire as well as wireless. This was the audion, or thermionic detector and relay of minute electric currents. He first applied it as the detector for use in the successful radio telephone system, to which he devoted all of his efforts from 1906 to 1909. In 1908 all of the battleship fleet of Admiral Evans was equipped with the De Forest radio telephone, and the success attained at that time was largely due to the efficiency of the audion detector. In 1908 warships of the British and Italian navies were also equipped with the De Forest telephone. But difficulties inherent to the arc type of transmitter which was then employed led De Forest to abandon this type, and from 1909 to 1911 most of his efforts were devoted to development of the “quenched spark” type of wireless telegraph transmitter, the germ of which he brought here from Germany. Here again the success achieved by his new company, the Radio Telephone Company, resulted in the imitation and adoption of the quench-spark transmitter by all other American wireless companies. The American De Forest Wireless Telegraph Company had in 1907 become the United Wireless Company which was, in turn, bought up by the
Marconi Company. Due largely to such issues the Radio Telephone Company was forced to suspend, and in 1911 Dr. De Forest became chief research engineer for the Federal Telegraph Company in San Francisco. There he developed the first practical automatic high-speed transmitting and recording system for wireless telegraphing — using the Poulsen arc transmitter, and the telegraphone and audion amplifier as recorder. Also the “diplex” method of sending two messages simultaneously. This company now uses the De Forest method of duplex sending and receiving, where the transmitter and receiver stations are separated by several miles, and connected by a telegraph wire — since adopted by the United States navy and the Marconi Company. In 1912 Dr. De Forest exhibited his audion relay or telephone repeater to the engineers of the American Telegraph and Telephone Company, which one year later purchased the exclusive wire telephone rights under twelve audion patents. As a result of this that company was enabled, early in 1915, to open up the transcontinental telephone service between New York and San Francisco. In 1913 Dr. De Forest returned to New York, reorganized and established the De Forest Radio Telephone and Telegraph Company. The audion amplifier, the ultraudion detector, the oscillion, or oscillating audion, as generator of alternating currents of any frequency, were rapidly perfected and marketed. In 1915 the American Telegraph and Telephone Company, using the oscillating audion and amplifier in large sizes and quantities, succeeded in telephoning without wires from the United States Navy Station at Arlington to Honolulu. The De Forest inventions were used throughout this work — as transmitter, detector, and amplifier at the receiver. The latest work of Dr. De Forest is the oscillion radio telephone system, which transmits speech and music with greater clearness than is possible over a wire. This transmitter is a large incandescent lamp, and as simple and reliable as the latter. It at last makes possible a small practical wireless telephone which can be quickly installed on shipboard, in isolated points, and a thousand places where wires are impractical and where the cost of a Morse operator is prohibitive. For such purposes and the broadcast distribution of music, amusement, and news, the radio telephone bids fair shortly to fill a field of even greater utility than the wireless telegraph. Dr. De Forest has taken out over one hundred patents in the United States and foreign countries, all on radio inventions, many of them being pioneer and basic in scope. He now resides at Spuyten Duyvil, New York City, and spends his entire time in his laboratory at Highbridge, New York City. The oscillion telegraph and telephone for aeroplanes and portable military sets are among his latest creations. The European War has established a demand for these abroad, as well as in this country.