SMITH, William Sooy, civil engineer, born in Tarlton, Ohio, 22 July, 1830. He was graduated at Ohio university in 1849, and at the United States military academy in 1853. He resigned in 1.854 and became assistant to Lieutenant-Colonel James D. Graham, of the United States topographical engineers, then in charge of the government improvements in the great lakes. In 1855 he settled in Buffalo, New York, and was principal of a high-school. In 1857 he made the first surveys for the international bridge across Niagara river, and was employed by the city of Buffalo as an expert to examine the bridge plans that were submitted, tie was then elected engineer and secretary of the Trenton locomotive-works, New Jersey, which was at that time the chief iron-bridge manufacturing company in this country, and he continued so until 1861. While serving in this capacity he was sent to Cuba by the company, and he also constructed an iron bridge across Savannah river, where he introduced improvements in sinking cylinders pneumatically. The beginning of the civil war stopped this work, and he was appointed lieutenant-colonel of Ohio volunteers and assigned to duty as assistant adjutant-general at Camp Denison. On 26 June, 1861, he was commissioned colonel of the 13th Ohio regiment and participated in the West Virginia campaigns, after which he joined the Army of the Ohio, and was present at. Shiloh and Perryville. He was promoted brigadier-general of volunteers on 15 April, 1862, and commanded successively the 2d and 4th divisions of the Army of the Ohio until late in 1862, after which he joined the army under General Grant and took part in the Vicksburg campaign as commander of the 1st division of the 16th corps. Subsequently he was made chief of cavalry of the Department of the Tennessee, and as such was attached to the staffs of General Grant and General William T. Sherman until, owing to impaired health, he resigned in September, 1864. Returning to his profession, he built, the Waugoshanee light-house at the western entrance of the Straits of Mackinaw, where in 1867 he sank the first pneumatic caisson, he aided in opening the harbor of Green Bay, Wisconsin, and has been largely engaged in building bridges. He built the first great all-steel bridge in the world, across Missouri river at Glasgow, Missouri, and was concerned in the construction of the Omaha and the Leavenworth bridges, as well as many others, including that over Missouri river at Plattsmouth, Nebraska General Smith has served on numerous engineering commissions, both for the government and for private corporations. He is a member of the American society of civil engineers, and was president of the Civil engineers' club of the northwest in 1880. His writings have been confined to reports and professional papers.