Letterman, Jonathan (1824–1872)

US surgeon. An army surgeon, he tended soldiers injured during skirmishes with American Indians (1849–62). Between 1862–64 he served as medical director of the Union's Army of the Potomac; his organization of the medical field service, including mobile hospitals and ambulances, laid the foundations for armies since then. Following the war he set up a private practice in San Francisco, California, and wrote Medical Recollections of the Army of the Potomac (1866). Letterman was born in Canonsburg, Pennsylvania.