The Salvager was first constructed as the United States Light House Service Tender Elm at the yards of Rice Brothers Company at East Boothbay, Maine in 1917. On 10 July 1917, there was a massive fire at the Rice Brothers shipyard which destroyed and damaged some vessels then under construction including the Elm. The Elm was a power-derrick barge, and built for the service and construction of aids to navigation in the Hudson River. It was single deck vessel constructed entirely of wood except for the casing around the engine space. It was fitted with a derrick mast (crane) and two booms one 68 feet long and the other 40 feet long, with gear and tackle operated by a steam-powered hoisting engine that was supplied with steam from a small vertical boiler. The Elm