LATTA, Alexander Bonnet, inventor, born in Ross county, Ohio, 11 June, 1821; died in Ludlow, Kentucky, 28 April, 1865. At an early age he worked in a cotton-factory, and subsequently in the navy yard in Washington, D.C. After becoming an expert mechanic he settled in Cincinnati, where he operated the first iron planing-machine that ever was used in that city. He became foreman of a ma-chine-shop, and constructed for the Little Miami railroad the first locomotive that was built west of the Alleghany mountains, he invented and patented a series of improvements in railway appliances, a few of which he succeeded in introducing. In 1852 he invented a steam fire-engine, which he constructed in nine months, and which was tried on 1 January, 1853. In October, 1853, he con-strutted a second, which contained several improvements and received a gold medal at the Ohio Mechanics' institute fair in 1854. He continued to build steam fire-engines until 1862, when he retired from active business. The boiler of Mr. Latta's engine was constructed of two square chambers, one within the other, the space between which chambers was the steam and water space of the boiler. The inner chamber, which was the fire-box, was filled by a series of horizontal layers of tubes arranged diagonally over each other, but forming one continuous coil. The water entered this coil at the lower end and passed upward into the annular space, where it was evaporated. Upon arriving at the scene of the fire, the rear of the engine was raised off the ground and supported by means of screws on the sides of the boiler, and the hind-wheels, thus clearing the ground, acted as fly-wheels. In 1863-'5 Mr. Latta introduced the manufacture of aerated bread into Cincinnati. He also made improvements in oil-well machinery.