Albert Abraham Michelson was born on December 19, 1852, at Strelno in Posen, now restored to Poland. When he was two years old, he was taken by his parents, Samuel Michelson and Rosalie (Przlubska), to the United States, and, after some fifteen years spent in Virgina City, Nevada, where his brother Charles was born, San Francisco became their home. There his sister Miriam, the author, was born, and the boy attended the high school. He was given, in unusual circumstances, an appointment in the U.S. Naval Academy at Annapolis, and after graduating in 1873 he became a midshipman in the U.S. Navy for two years and was afterwards appointed instructor in physics and chemistry in the Naval Academy in 1875, holding the appointment until 1879. His next year was spent in the Nautical Almanac Office in Washington, and then he studied for two years at the College of France, and at Heidelberg and Berlin. In 1882 he became Professor of Physics in the Case School of Applied Science at Cleveland, Ohio. After seven years he went as Professor of Physics to Clark University, Worcester, Mass., and remained there until 1892. He was then appointed Professor at the head of the Ryerson Physical Laboratory, Chicago ; this appointment he held until shortly before his death, which occurred on May 9, 1931. He married Miss Edna Stanton of Lake Forest, Illinois, in 1899, and they had a son and two daughters. This in brief contains the history of his official appointments : how he filled the various posts is another matter.