[From wright20.com]

Gladys Caldwell Fisher’s model of the Boulder Dam (now known as the Hoover Dam) and surrounding landscape celebrates the Art Deco inspired structure that impounds the largest reservoir in the United States. Her model of the dam, a triumph of American engineering and design, features side panels with stylized Art Deco reliefs representing flood control, power, irrigation, navigation, and water supply to one side and a wing-spread eagle to the other side. The model opens up to reveal the detailed diversion tunnels while the interiors of the panels list the consultants, contractors, and government officials (up to and including Franklin Delano Roosevelt) involved with the project, and specifications for the dam’s structure, such as the diameter of the penstocks and the amount of concrete used to complete the Boulder Canyon Project. Few examples of this striking and detailed model are known.