1922 Encyclopædia Britannica/Michelson, Albert Abraham

MICHELSON, ALBERT ABRAHAM (1852-), American physicist, was born in Strelno, Germany, Dec. 19 1852. His parents moved to San Francisco, Cal., where he studied in the public schools. He graduated from U.S. Naval Academy in 1873 and was instructor in physics and chemistry there during 1875-9. He was then for a short time in the Nautical Almanac office. From 1880 to 1882 he studied in Berlin, Heidelberg and Paris. He resigned from the navy in 1881. In 1883 he was appointed professor of physics at the Case School of Applied Science, Cleveland, O., and six years later accepted a similar position at Clark University. In 1892 he was appointed professor and head of the department of physics at the university of Chicago. He early directed his researches to the velocity of light and while in Cleveland invented his interferometer (see ), which enabled him to measure distances by means of the length of light-waves. In 1892 he was a member of the Bureau Internationale des Poids et Mesures and in 1897 of the International Committee of Weights and Measures. He was made president of the American Physical Society in 1901 and of the American Society for the Advancement of Science in 1910. He received medals and prizes from many learned societies and in 1907 was awarded the Nobel Prize for physics. In 1920 he was able to demonstrate by means of light-interference that the diameter of Alpha Orionis was 260,000,000 miles. This was the first computation ever made of the size of a star. He was the author of numerous papers on light and in 1903 published Light Waves and Their Uses, being Lowell lectures for 1899. In 1921 he was awarded the gold medal of the Society of Arts, London. (For the &ldquo;Michelson-Morley experiment,&rdquo; in interference of light, with its bearing on the Einstein theory, see .)