Under tab, "Power Plant" Printing on bottom states, "1654-42 US Navy Yard, Charleston, SC. October 30, 1942. Contract NOy-4217. Deaerating heaters in parallel service in Power Plant. Close up showing water regulating valve and by pass etc. File 13666."
Under tab, "Power Plant" Printing on bottom states, "1655-42 US Navy Yard, Charleston, SC. October 30, 1942. Contract NOy-4217. Deaerating heaters in parallel service in Power Plant for picture of old single unit see photograph-File 11473. File 13667."