Black and white photographic image of the visitors' gallery inside Hoover Dam's power plant. Written on the front of the postcard: "Visitors gallery, power plant, Boulder Dam."
An image of Rotary Club members having lunch at Boulder Dam while an unidentified man gives a speech. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of a man looking at Hoover Dam's downstream face and the outlet works in the walls of Black Canyon. Note: Boulder Dam was officially renamed Hoover Dam in 1947.