A photograph front and side view of the Boulder Dam Hotel.

Principles involved in the signing of the Boulder Dam bill. L-R: Elwood Mead, Phil Swing, President Calvin Coolidge, Sen. Hiram Johnson, Addison T. Smith, and W.B. Matthews. Text on photo reads: "Public Service History Written as Boulder Dam Bill Is Signed. December 21, 1928. Elwood Mead, Commissioner of Reclamation. Phil Swing, M. C. Cali., Author Boulder Dam bill House of Representatives. President Coolidge. Senator Hiram Johnson, Author Boulder Dam bill in United States Senate. Addison T. Smith, M. C. Idaho, Chairman, Committee on Reclamation, House of Representatives. W. B. Matthews. General Counsel, Boulder Dam Association, Los Angeles."

Two images of the front view of the Boulder Dam Hotel in Boulder City, Nevada.

An image of the Boulder Dam Power Decennial plaque, which was made for the ten year anniversary of Boulder Dam, renamed Hoover Dam in 1947. Depicted on the sign is an outline of the downstream face of the Hoover Dam, along with outlines of the state seals of Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming. Transcribed from text across the sign: "Boulder Dam, Power Decennial. Flood Control - Irrigation - Power. Saluting Boulder Dam On Its Tenth Year Of Commercial Power Production. 1936-1946. Honoring The People Of The Colorado River Basin States. Whose initiative brought forth Boulder Dam, making possible: The maximum utilization of the water resources of this great river system; The prevention of floods; The conservation of water; The availability of hydroelectric energy to a wide area."

The front and back cover of the postcard booklet of the Boulder Dam.