Lee de Forest

Inventor

• Born: August 26, 1873
• Birthplace: Council Bluffs, Iowa
• Died: June 30, 1961
• Place of death: Hollywood, California

American inventor

De Forest’s three hundred patents mark him as a great American inventor. For his most famous invention the thermionic grid-triode he was known as one of the founders of radio.

Areas of achievement Invention and technology, radio

Early Life

Lee de Forest was born in Council Bluffs, Iowa, but grew up in Talladega, Alabama, where his parents moved when he was six. His father, Henry Swift de Forest, was a Congregationalist minister of Huguenot background who served as president (1879-1896) of Talladega College, for black students. Lee’s mother, descended from the Mayflower’s John Alden, was among the first graduates of Iowa’s Grinnell College. Lee had a sister, Mary, born 1872, and a brother, Charles, born 1878.

Even when young, de Forest was aware of his destiny as an inventor. He had a passion to understand the workings of all things mechanical and electrical, often building model foundries and even castles based on his observations. De Forest also discovered early that mechanical prowess can create happiness: On Christmas Day, 1879, he delighted the children of his poverty-stricken town by solving problems that had kept a model train from working. His creations drew the admiration of upper-class Talladega whites, who otherwise held Lee’s “do-gooder” family in contempt.

As a teenager, de Forest attended Mt. Hermon School in Massachusetts, then entered a three-year course in mechanical engineering at the Sheffield Scientific School at Yale University on a scholarship endowed by a wealthy ancestor. After he was graduated in 1896, de Forest returned for graduate studies with such leading academic scientists of his time as Josiah Willard Gibbs and Henry Bunstead.

In his twenties, the intense, blue-eyed de Forest was thin, almost gaunt, shabbily dressed in shiny suit and hand-me-down straw hat. He already displayed what would become lifelong traits: a strong preference for applied over theoretical science, idealistic excitement over possible uses for his inventions, and keen disappointment at what he considered their misapplications. An introvert, he lacked the business acumen of such innovators as Nicola Tesla, Guglielmo Marconi, and Thomas Edison, all of whom he longed to emulate. However, he protested loudly if he received less credit than he thought was his due for his inventions. Throughout his life, his companies were engaged in costly, protracted lawsuits over patent rights. Not that de Forest’s work went unrecognized. As early as his first postgraduate year, he won national acclaim when the Scientific American for March, 1897, published a discussion of his “equationer,” a machine he devised that would solve quadratic equations.

Bunstead had introduced him to Hertzian radio waves, however, and radio transmission was to become his principal life interest. In 1899, de Forest produced one of America’s first doctoral theses on the subject now known as radio: “Reflection of Hertzian Waves from the Ends of Parallel Wires.”

Life’s Work

De Forest got his first job at a dynamo factory of Western Electric in Chicago. He spent his free hours trying to develop a Hertzian wave detector suitable for receiving radio broadcasts. Hearing of this work, his supervisors at Western Electric first gave him the use of a laboratory during nonworking hours, then released him from telephone work altogether, telling him to “Do as you damn please.” For several years thereafter he concentrated exclusively on wireless data transmission, especially its journalistic applications. In 1904, his electrolytic wave detector was used by European reporters transmitting news of the Russo-Japanese war, until the Japanese put a stop to this practice. In 1906, he made good on an earlier failed attempt to transmit an on-the-spot account of the International Regatta contest.

In the meantime, he had organized his own firm, De Forest Wireless Telegraph Company. At first privately financed, the company later sold shares to the public. Two events brought the company to disaster in 1906: A patent infringement suit went against it, and de Forest’s associates released questionable stories to the media in an attempt to influence the price of shares. De Forest resigned, selling a group of patents to his former partners for a mere one thousand dollars.

Painful though it was, this marked an important transition for de Forest, from telegraphy (signal transmission) to radio (voice transmission). In 1907, he patented a Hertzian wave detector, the Audion, which was vastly superior to his earlier invention and to other scientists’ inventions then in use. It was the famous thermionic grid-triode vacuum tube, similar to a two-element device invented by John Ambrose Fleming in 1904, except that de Forest had inserted a third electrode as a stabilizer between cathode and anode. Also in 1907, de Forest made experimental voice broadcasts to the public in New York City. In 1910, he broadcast a live operatic performance by Enrico Caruso.

By most accounts, however, it was not until 1912 while working at the Federal Telegraph Company in Palo Alto, California that de Forest recognized the true potential of his device. In that year he realized that he could amplify high-frequency radio signals by “cascading” a series of Audion tubes. In so doing, he increased the device’s capability above what could have been accomplished by the previous method of raising the voltage on a single tube. Starting with a radio signal that was very weak, de Forest strengthened it by placing transformers between tubes so that the signal from each tube was amplified before passing into the next one. Moreover, experimentation showed him how to produce oscillation by feeding part of the signal from his triode vacuum back into its own grid. Used with antennae, this oscillating signal greatly improved the power and quality of voice or music transmissions over what was produced by the crude transmitters of the day. Modifications made de Forest’s inventions usable for either transmission, receipt, or amplification of radio signals.

These inventions were milestones for both radio and long-distance telephone communication, bringing tremendous changes in everyday life throughout the industrialized world. De Forest’s success led to his becoming a charter member (and afterward president) of the Institute of Radio Engineers in 1912; three years later, he received the Elliot Cresson Medal of Honor from the Franklin Institute. Unfortunately, as so often in de Forest’s life, this triumph was alloyed by conflict and disappointment: In 1909, his second firm, the De Forest Radio Telephone Company, had begun to fall apart, again because of his associates’ questionable practices. In 1912, the process culminated in the indictment of de Forest on charges of using the mails to defraud the public. Ironically in light of his triode successes, he was accused of promoting a “worthless” device, the Audion tube. Not until early 1914 was the case resolved, with two of the company’s partners convicted and jailed, but with de Forest and another partner acquitted.

By now, de Forest had become highly distrustful of businessmen. Unsure of his ability to manufacture his own inventions, he began to sell his patents, sometimes at prices far below their true worth. For example, according to an early biographer, de Forest’s disillusionment was intensified when in 1912 he sold his Audion patent to American Telephone and Telegraph for fifty thousand dollars only to learn that the company had earmarked ten times that amount should it become necessary to close the deal.

Nevertheless, proceeds from this sale in addition to ninety thousand dollars from the sale of the triode to the Bell System in 1914 enabled de Forest to organize a new company in New York. This firm, which manufactured radio tubes and other equipment for military and civilian use, brought de Forest a steady income until 1923, when he sold it to devote full time to work on sound motion pictures. For the next four years he spent much time in American theaters demonstrating what he called Phonofilm, which recorded sound optically on the film itself. This principle is similar to the one used in motion pictures today, but de Forest, unable to achieve high-quality sound, failed to interest film producers of the time. One film critic, Karl Kitchen, wrote,

The invention, . . . which has been perfected by Dr. Lee de Forest, does all that is claimed for it. The action and the sound synchronize perfectly but what of it? The music sounds like ordinary phonograph music which is very different from that of a symphony orchestra, to put it mildly. . . . Besides, the theatre-going public has not evidenced any interest in talking pictures.

As before, rival inventors brought patent litigation against de Forest, and he against them. One important case against Elias Reis over the “film-slit” method of producing motion-picture sound was decided in de Forest’s favor, but most of the other suits ultimately went against him. During the late 1920’s, he worked on another device for motion-picture theaters: a television process using a mechanical scanner, which also proved unsuccessful. His next enterprise, in the 1930’s, was the production of Audion-diathermy machines for medical use. World War II saw him engaged in military research for Bell Telephone Laboratories.

De Forest was embittered by the claims of those who disputed the priority of his inventions and by the exploitation of radio by others for enormous profit. (It should be noted, however, that the work of other scientists was needed to improve on his original ideas, just as he improved on those of his predecessors; for example, H. D. Arnold and Irving Langmuir enhanced the effectiveness of de Forest’s triode through their efforts to attain the highest possible vacuum.) Yet what galled de Forest far more was the insipid, commercial uses to which his inventions especially radio were put. In his fifties, this lifelong devotee of Beethoven and Wagner confronted a group of radio executives with the following words:

What have you done with my child? The radio was conceived as a potent instrumentality for culture, fine music, the uplifting of America’s mass intelligence. You have debased this child, you have sent him out in the streets in rags of ragtime, tatters of jive and boogie-woogie, to collect money from all and sundry.

Despite his anger over “the dreary dollar-chasing uses of the ether,” de Forest continued to believe strongly in the future of electronics and its value for human life. He remained involved in the field almost to his death. He was eighty-four when he received his last patent in 1957, on an automatic telephone dialing device.

Also relatively late in life, de Forest received recognition commensurate with the magnitude of his inventions. Among his many honors were the Prix Saint Tour of the French Academy, honorary doctor of science degrees from Yale and Syracuse Universities, and the Cross of the Legion of Honor from the French government. He was even considered for the Nobel Prize in Physics. Although he never achieved that honor, he was world famous as the founder of radio and the cofounder of television.

De Forest was married four times. His final marriage, to film actor Marie Mosquini in 1930, was a happy one that lasted the rest of his life. As a widow, she donated his papers and other materials to the Foothill Electronics Museum in Los Altos, California, established in 1969.

Despite the immeasurable value of de Forest’s inventions radio alone was a billion-dollar industry by the time he reached age fifty de Forest left an estate worth only twelve hundred dollars when he died in Hollywood, California, on June 30, 1961.

Significance

Although only a few of de Forest’s three hundred patents are considered important today, it is impossible to overstate the significance of his thermionic grid-triode and his use of it as an oscillator and amplifier. As electronic advances, these are on a par with the much later development of the transistor (1947) and of solid-state electronics (the 1950’s). Even greater is the significance of the triode as a social, educational, and cultural development. Radio, with the triode at its heart, has brought lectures, musical and dramatic performances, and news events from congressional deliberations to military battles into the homes of millions around the world. Like television after it, radio brought the world closer together, providing, as de Forest put it, “a new world cement.”

His vision concerning the practical benefits of his inventions to humanity mark him as a quintessential American of the late nineteenth century. Also characteristic of a child of that era were de Forest’s individualism and his extreme drive and discipline; often while working in his laboratory he would go without food or sleep, and at least once he fainted from illness and exhaustion.

If these are the traits that fueled his successes, he had other traits, equally typical of his period, that account for his many failures, above all a naïve faith that others shared his idealism. Once this faith was broken, de Forest mirrored ordinary citizens’ growing disillusionment with and distrust of American businessmen and large corporations.

Radio and other inventions to which de Forest contributed have broadened people’s horizons, but it remains to be seen whether advanced communications technology will fulfill his vision of binding together “the various peoples . . . of the globe in a quickened intelligence, a livelier sympathy, a deeper understanding. This, in time, would spread the knowledge which alone will end war.”

Bibliography

Carneal, Georgette. A Conqueror of Space: An Authorized Biography of the Life and Work of Lee de Forest. New York: Horace Liveright, 1930. A biography that praises its subject uncritically and passes over de Forest’s share of responsibility for business reverses. Valuable for its vivid anecdotes evoking de Forest’s milieu and character, and for its technical descriptions of his experiments.

De Forest, Lee. Father of Radio: The Autobiography of Lee de Forest. Chicago: Wilcox & Follet, 1950. A biased and rather immodestly titled autobiography that amply reveals the character of de Forest. Contains his 1920 paper on the development of the triode, as well as a list of his other inventions.

Evans, Harold, with Gail Buckland and David Lefer. They Made America: From the Steam Engine to the Search Engine, Two Centuries of Innovators. New York: Little, Brown, 2004. De Forest is one of seventy American inventors and entrepreneurs who are profiled in this book.

Levine, Israel E. Electronics Pioneer: Lee de Forest. Milwood, N.Y.: Associated Faculty Press, 1964. A straightforward, clearly written account of de Forest’s life for nontechnical readers.

MacLaurin, W. Rupert. Invention and Innovation in the Radio Industry. Salem, N.H.: Ayer, 1971. Stresses the economic consequences of major technical contributions to the development of radio.

Miessner, Benjamin Franklin. On the Early History of Radio Guidance. San Francisco, Calif.: San Francisco Press, 1964. Contains an impartial, well-documented account of the development of the triode, including de Forest’s contributions.

Zouary, Maurice H. De Forest, Father of the Electronic Revolution, the Tube That Changed the World: How the Vast New Electronics Industry Came to be Born. Bloomington, Ind.: First Books Library, 2000. A biography of de Forest that focuses on his invention of the Audion tube.

Related Articles in Great Events from History: The Twentieth Century

1901-1940: November 16, 1904: Fleming Patents the First Vacuum Tube; 1913: Edison Shows the First Talking Pictures; January 25, 1915: First Transcontinental Telephone Call Is Made; October 21, 1915: First Demonstration of Transatlantic Radiotelephony; 1920’s: Radio Develops as a Mass Broadcast Medium; August 20-November 2, 1920: Radio Broadcasting Begins; November, 1932: Antitrust Prosecution Forces RCA to Restructure.

1941-1970: December 23, 1947: Invention of the Transistor.