ENGINEERS, Corps of, a branch of the United States army which takes charge of the construction and repair of fortifications, both temporary and permanent, military reconnoiter ing and surveying, the selection and planning of camp sites, the construction and maintenance of roads, railroads, bridges, storehouses, etc., and divers other technical services which are not under the supervision of special branches of the army. It also superintends river and harbor improvements, the collection and preser vation of documents relating to the Washington aqueduct and public buildings in the District of Columbia and the construction of bridges and roads in the Crater Lake and Yellowstone National Parks. The Panama Canal was built under engineer officers.
Engineer officers were authorized by Con gress on 16 June 1775 and in the same year Col. R. Gridley became chief engineer. Many French engineers served with the United States army during the Revolution. A corps of artillerists and engineers was established by the act of 9 May 1784. In 1802 the artillery and engineers were separated and the Corps of En gineers was established. This was gradually mcreased in size until the present establishment is 505 officers, one band, seven regiments and two mounted battalions. In 1813 appointments were first made to the rank of topographical engineer. After various vicissitudes, the topo graphical service of the army was organized as the Corps of Topographical Engineers in 1838. In 1863 this corps was merged in the Corps of Engineers.
Engineer officers are appointed, in general, from West Point, although competitive exami nations are held which are open to civilian engineers. Commissions in the engineers are
generally given to those West Point cadets with the highest academic standing. Officers in the Corps of Engineers are considered as in the line when they are on service with engineer troops. Otherwise they are staff officers.
During the Great War the uses of engineer troops and the organizations which they form have undergone great diversification. Whereas the engineer troops of the United States army were formerly grouped into pioneer regiments, mounted pioneer battalions and pontoon bat talions, there are now also labor regiments, railroad regiments, lumbering regiments and so on indefinitely, made up from men in the Na tional Army or National Guard and under eng.ineer officers. The technical training of officers of the Corps of Engineers is divided be tween the United States Engineer School at Washington and the Army Field Engineer School at Fort Leavenworth. The Royal Engi neers of the British Army, the atechnische Truppen') of Germany and the Engineer Corps of the French Army correspond very closely to the United States Corps of Engineers, but per form work which belongs to the American Sig nal Corps as well. The foreign corps also differ from the American in that they draw in general from technically trained men, whereas in times of peace American engineers receive the greater part of their training after enlistment. See ARMY ORGANIZATION; UNITED STATES, ARMY OF.