SEMMES, Alexander Aldebaran, naval officer, born in Washington, D. C., 8 June, 1825; died in Hamilton, Virginia, 22 September, 1885. He entered the navy as a midshipman, 22 October, 1841, attended the naval academy at Annapolis, and became a passed midshipman, 10 August, 1847. He was promoted to master, 11 August, 1855, and to lieutenant, 15 September, 1855. During the civil war he rendered creditable service m command of the steamer "Rhode Island" on the Atlantic coast blockade in 1861, and in the steamer "Wamsutta" on the South Atlantic blockade, during which he conducted numerous engagements with forts and batteries on the coasts of Georgia and Florida, where he captured several blockade-runners in 1862-'3. He commanded the monitor "Lehigh" in the bombardment of Fort Pringle, and participated in the operations at Charleston until that city surrendered. He cooperated with Grant's army, fought the Howlett house batteries, and was present at the fall of Richmond in 1865, he was commissioned a commander, 25 July, 1866, promoted to captain, 24 August, 1873, and stationed at the Pensacola navy-yard in 1873-'5. In 1880 he was president of the board of inspection, after which he was commandant of the navy-yard at Washington. He was commissioned commodore, 10 March, 1882, and was in command of the navy-yard at the time of his death, but had left the city on account of his health.