sentences:  The factory complex consists of a series of interconnected one to five-story heavy timber frame, brick, steel, and concrete industrial buildings.The complex also includes a coal trestle (1907); two small buildings erected in the 1940s (a brick fire pump house and a concrete block workshop); an electrical substation (1948-1954); and a one-story brick office building (1937).The Chatham Manufacturing Company consolidated its operations at Elkin in 1940, and the Winston-Salem plant was subsequently purchased by the United States Government.