DOWNES, John, an American naval officer, born in Canton, Mass., in 1786, died in Charlestown, Aug. 11, 1855. He entered the navy as a midshipman in June, 1802, and was in the frigate New York during the war with Tripoli. In May, 1803, he distinguished himself in a boat attack upon some Tripolitan feluccas. In March, 1807, he was made lieutenant, and in the war of 1812 he served as executive officer of the frigate Essex, Capt. Porter, during her celebrated cruise in the Pacific. Among her numerous prizes was the whale ship Georgiana, which Capt. Porter fitted as a cruiser, with 16 guns, named the Essex Junior, and placed under the command of Lieut. Downes, who retained this position until the capture of the Essex and the conversion of the Essex Junior into a cartel. In 1813 he was promoted to the rank of master commandant, and in 1815 he commanded the brig Epervier in the squadron employed against Algiers under Decatur. On June 17, 1815, the Epervier assisted in the capture of the Algerine frigate Mashouda off Cape de Gatt. Two days afterward the Epervier and three of the smaller vessels of the squadron captured the Algerine brig of war Estido, 22 guns and 180 men, off Cape Palos. After the conclusion of peace with Algiers, Decatur transferred Downes to his own ship, the Guerriere. In March, 1817, he became captain, and from 1819 to 1821 commanded the frigate Macedonian in the Pacific. In 1828-'9 he commanded the Java in the Mediterranean, and from 1832 to 1834 the squadron in the Pacific. On his way to his station he attacked (Feb. 6, 1832) and nearly destroyed Quallah Batoo, on the coast of Sumatra, where an outrage had been committed on an American vessel. His sea service terminated with his cruise. From 1837 to 1842, and from 1850 to 1852, he commanded the navy yard at Boston.