David Bates Douglass, an American engineer, born in Pompton, N. J., March 21, 1790, died in Geneva, N. Y., Oct. 19, 1849. He graduated at Yale college in 1813, entered the army as second lieutenant of engineers, and for his share in the defence of Fort Erie was made first lieutenant, with the brevet rank of captain. In 1815 he was appointed assistant professor of natural and experimental philosophy at West Point, in 1819 was astronomical surveyor of the boundary commission from Niagara to Detroit, and in the summer of 1820 accompanied Governor Cass in a similar capacity to the northwest. In August he became professor of mathematics at West Point, with the rank of major, and in 1823 professor of civil and military engineering. In this science he soon acquired a wide reputation. He was employed by the state of Pennsylvania during the summer recesses from 1826 to 1830 as a consulting engineer, and was charged with several of the more difficult parts in its system of public works. In 1831 he resigned his professorship and became chief engineer of the Morris canal. In 1832 he was appointed professor of civil architecture in the new university of the city of New York, and prepared the designs for its building.

In June, 1833, he commenced his surveys for supplying New York with water, and in November submitted his first report, showing how to obtain a supply from the Croton river. In 1835, his plan having been accepted, he was elected chief engineer, and had accomplished the preliminary work when he was superseded. In 1839 he planned and laid out Greenwood cemetery. He was president of Kenyon college, Ohio, from 1841 to 1844, when he returned to the vicinity of New York. In 1845-'6 he laid out the cemetery at Albany, and in 1847 was employed in developing the landscape features of Staten Island. In 1848 he laid out the Protestant cemetery at Quebec, and was elected professor of mathematics and natural philosophy in Hobart college, Geneva, N. Y.