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Louis Winslow Austin, Physicist, (b: October 30, 1867 d: June 27, 1932 Orwell, Vermont, Washington, D.C.), was educated at Middlebury College, graduating in 1889; Ph.D., University of Strasbourg, 1893. He was an instructor and assistant professor at the University of Wisconsin, 1893- 1901 and carried out research work at the University of Berlin, 1901-02.

In 1904 he became associated with the Bureau of Standards. Appointed chief of the Bureau's laboratory for special radio transmission research in 1923, he concentrated on the study of static, the influence of temperature, humidity, magnetic storms and sunspots on radio. Dr. Austin headed the United States Naval Research Laboratory, 1908-23, and was chief of the Radio Physics Laboratory, 1923-32.

As a result, in 1927, he was awarded the Medal of Honor of the Institute of Radio Engineers for his pioneer work in the quantitative measurement and correlation of factors involved in radio transmission. He was president of the Institute in 1914.

Under the direction of Austin, as head of the Naval Radio Telegraphic Laboratory at the Bureau of Standards, the Navy Department, in 1909 and 1910, conducted long-distance wireless tests between the scout cruisers Birmingham and Salem and the Fessenden station at Brant Rock, Massachusetts. While the cruisers voyaged to Liberia and back, Austin measured the received impulses from the ships on the 3,750 and 1,000 meter wavelengths, in order to determine whether absorption varied with frequency.

The signals were plotted from day to day, and Austin, assisted by Dr. Louis Cohen, research engineer for the National Electric Signaling Company, aimed to determine as nearly as possible the law which governs long distance transmission of electric waves to establish the relations which connect the principal factors such as distance, wavelength, height of antenna, with the relative strength of the current at the sending and receiving stations.

It had been known for some time that over comparatively short distances the received current falls oil approximately in inverse ratio with the distance. The Austin-Cohen formula resulted. Thus, for a given signal current on a given wavelength, it was possible to derive by formula the received current which would result at a distant point.

Duddell and Taylor in 1905 had determined that the received energy vanished over water nearly in proportion to the distance. Their observations were confined to short distances over the English Channel. Austin found that their theory held true from 100 to 200 miles, beyond which the values of the received current disappeared more rapidly. This was caused by absorption.

Austin assumed that absorption was proportional to the distance. Cohen, however, discovered the law connecting absorption and frequency. This took Austin's work out of the realm of the empirical, for he had dealt chiefly with two wavelengths, and gave the formula a general nature. Thus it was appropriate that the formula became universally known as the Austin-Cohen formula.

Austin also attacked the popular belief that lightning is the sole source of static; what he described as upside-down lightning he believed to be the major cause, since it consisted of the steady discharge of electrical energy into a conducting layer estimated to exist at a height of from sixty to eighty kilometers above the earth. He added that he believed the Heaviside layer produces refraction of waves rather than reflection.

"Our knowledge concerning the atmospheric disturbances is still very meager"

Austin at a meeting of the Section of Terrestrial Magnetism and Electricity of the American Geographical Union, Washington, D. C., April 30, 1925.

In general, atmospherics are stronger on the longer wavelengths. Except for the effects of local storms, they are nearly always stronger in the afternoon and night, while for the higher frequencies this increase in strength is confined usually to the night alone. Static is stronger in summer than in winter, in the south than in the north and on the land than on the ocean.

A large proportion of the atmospherics appear to be directive that is, to come from definite regions, or centers, as mountain ranges, rain areas or thunderstorms. It is also reasonably certain, Austin found, that at least most of the longwave disturbances travel along the earth with a practically vertical wave front like the signals that a considerable portion of static is oscillatory in character.

Austin observed that in Europe about 30 per cent of static disturbances originated in thunderstorms, while 75 per cent were associated with rain areas. In the United States, near the Atlantic coast, disturbances in general came from the southwest, while on the California coast they came from permanent centers in the neighboring mountains. In the Middle West the direction was found to be variable depending upon thunderstorms and rain areas.

"It is believed, said Austin, that even in thunderstorms some of the heaviest disturbances do not come from the lightning itself, but the nature of these non luminous sources of such great power is still a matter of conjecture".

Source: Orrin E. Dunlap Jr., Radio's One Hundred Men of Science

Louis Winslow Austin (b. Oct. 30, 1867, Orwell, Vt., U.S. d. June 27, 1932, Washington, D.C.), physicist known for research on long-range radio transmissions. He was educated at Middlebury College, Vermont, and the University of Strasbourg, Germany. In 1904 he began work on radio transmissions for the U.S. Bureau of Standards.

In 1908 Austin became head of a naval radiotelegraphy laboratory at the bureau (later to become the Naval Research Laboratory) and from 1923 until 1932 was chief of the bureau's laboratory for special radio transmission research.

Austin's work involved long-range transmission experiments, most notably a study, conducted in 1910, that tested radio contact between ships travelling between the United States and Liberia. This work helped Austin and his collaborator Louis Cohen to develop the Austin-Cohen formula for predicting the strength of radio signals at long distances. Austin's later work centred on the study of radio atmospheric disturbances, i.e., "static."

Source: Britannica Online

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