Printing on bottom states, "791-42, US Navy Yard, SC, May 25, 1942, Front view of new building (extension to bldg. # 46) housing the 5000 CFM-I.R. Electric driven Air Compressor. File 12465."
Under tab, "Power Plant" Printing on bottom states, "384-42 US Navy Yard, Charleston, SC. March 25, 1942. Improvements to Power Plant, Contract NOy-4217. Steam Distribution Line area 2, View of Chamber 2. File 12449."