"3423 Interior view of the Nevada Valve House, looking downstream. Note N-6 Emergency Gate being installed. August 27th, 1935.
3424 Nevada Valve House roof, looking upstream. Note the low strength pedestals and the double layer of railroad iron
being placed. August 27th, 1935.
3407 Switchyard control house, yard and present sub-station. View taken looking toward Boulder Dam. August 26th, 1935.