ROACH, John, ship-builder, born in Mitchellstown, County Cork, Ireland, in 1815 ; died in New York city, 10 January, 1887. At the age of fourteen he came penniless to New York, and obtained work from John Allaire, in the Howell iron-works, New Jersey. In 1840 he went to Illinois to buy land, but ha returned to New York, and worked as a machinist for several years, and then established a foundry with three fellow-workmen. The explosion of a boiler nearly ruined him financially, but he rebuilt his works, which were known as the Aetna iron-works, Here he constructed the largest engines that had been built in the United States at that time, and also the first compound engines. In 1868 he bought the Morgan iron-works in New York city, and also the Neptune, Franklin Forge, and Allaire works, and in 1871 the ship-yards in Chester, Pennsylvania, that were owned by Rainer and Sons. He established a ship-building plant that covered 120 acres, and was valued at $2,000,000, under the name of the Delaware river iron ship-building and engine works, of which he was the sole owner, and where he built sixty-three vessels in twelve years, chiefly for the United States government and large corporations. Among these were six monitors that were ordered during General Grant's administration. The last, vessels that he built for the United States navy were the three cruisers " Chicago," " Atlanta," and "Boston," and the despatch-boat " Dolphin." On the refusal of the government to accept the "Dolphin" in 1885, Mr. Roach made an assignment, and closed his works; but they were reopened when the vessel was accepted, He constructed altogether about 114 iron vessels, and also built the sectional dock at Pensacola, Florida, and the iron bridge over Ilarlem river at Third avenue, New York city, in 1860.