Black and white image of equipment being lowered into Hoover Dam. People are watching from the lookout point on the Nevada side of the dam. 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.

Black and white montage of a person sitting in a small boat near Hoover Dam's upstream side. The lake and canyon portion of the image look to be from a photograph, but the dam seems to be a drawing. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

Black and white image of Hoover Dam's crest and a sailboat on Lake Mead, as seen from the Nevada upstream side of the dam. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

Black and white image of a crowd of people gathered together for the Boulder Junction, a ceremony celebrating the beginning of work on Boulder Canyon Project and the beginning of construction on a Union Pacific Railroad from Boulder Junction (Bracken Junction) to the dam site. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

A portrait of Jean R. Walton, an acting project engineer for the San Diego Project, in Escondido, California.

U.S. Air Force Thunderbirds maintenance officer "Monty" Montgomery, Nellis Air Force Base, Nevada.