Encyclopædia Britannica, Ninth Edition/Mitchel, Ormsby McKnight
MITCHEL, Ormsby McKnight (1810-1862), American general and writer on astronomy, was born in Union county, Kentucky, August 28, 1810. He began life as a clerk, but, obtaining an appointment to a cadetship at West Point in 1825, he graduated there in 1829, and became assistant professor of mathematics in 1831. Subsequently he was called to the bar, but forsook law to become professor of mathematics and natural philosophy at Cincinnati college. There he established an observatory, of which he became director. From 1859 to 1861 he was director of the Dudley observatory at Albany. He took part in the war as brigadier-general of volunteers, and for his skill and rapidity in seizing certain important strategic points was on April 11, 1862, made major-general. He died of yellow fever at Beaufort, South Carolina, October 30, 1862. Besides making important improvements on several astronomical instruments, Mitchel was the author of several works on astronomy, the principal of which are The Planetary and Stellar Worlds (1848) and The Orbs of Heaven (1851). See Memoir by Headley (1865).