MASON, James Louis, soldier, born in Providence, Rhode Island, in 1817; died in San Francisco, California, 5 September, 1853. He was graduated at the United States military academy in 1S36, standing second in his class, and was made 2d lieutenant in the corps of engineers. During 1836-'46 he served as assistant in building Fort Adams, Newport, Rhode Island, as superintendent engineer of the construction of the pier, dike, and light-house on Goat island in Newport harbor, and of the building of Fort Montgomery, New York He participated in the war with Mexico, and was engaged at the siege or V era Cruz and the battle of Cerro Gordo, becoming captain of engineers on 24 April, 1847. Subsequently he was present at the capture of San Antonio and the battles of Contreras, Churubusco, and Molino del Rey, receiving wounds that prevented his return to active service until 1850. Thereafter he served as superintending engineer of Fort Marion and Fort Clinch, Florida, and in the construction of the defences at Fort Point, San Francisco, California For his services in Mexico he received the brevets of major and lieutenant-colonel. Besides various military and scientific memoirs and reports, he published "An Analytical Investigation of the Resistante of Piles to Superincumbent Pressure" (1850).