Etna Iron Works

The Etna Iron Works (sometimes rendered as Ætna Iron Works) was a 19th-century ironworks and manufacturing plant for marine steam engines located in New York City. The Etna Works was a failing small business when purchased by ironmolder John Roach and three partners in 1852. Roach soon gained full ownership of the business and quickly transformed it into a successful general-purpose ironworks.

Roach took advantage of the American Civil War to transform the Etna Works into one of New York's leading manufacturers of marine steam engines. By the end of the war, he was in a position to acquire the businesses of most of his major New York competitors, who had fallen on hard times. Roach subsequently consolidated his operations at the Morgan Iron Works, and some time afterward rented the Etna Works to the inventor Thomas Edison, who turned it into a dynamo factory. The Roach family sold the former Etna Works property in 1887. The Etna Works buildings, along with the street on which they were located, were later liquidated in a city redevelopment.

Notable achievements of the Etna Iron Works include the building of the steam-operated Third Avenue Harlem Bridge in 1864, and the manufacture in the 1860s of the engines for the giant ironclad USS Dunderberg and for the passenger steamers Bristol and Providence, the latter two of which were the largest marine engines built in the United States to that date.

John Roach emigrated from Ireland to the United States in 1832 at the age of sixteen, eventually obtaining employment as a common laborer at the Howell Works of James P. Allaire at an initial wage of 25c a day. After securing an apprenticeship as an ironmolder at Howell Works, Roach later transferred to Allaire's other plant, the Allaire Iron Works in New York, where he learned the manufacturing method for marine steam engines. Roach would remain an employee of Allaire's for twenty years.