An image of Rotary Club members having lunch at Boulder Dam while an unidentified man stands up to give a speech. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

An image of Rotary Club members having lunch at Boulder Dam while an unidentified woman stands up to give a speech. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

An image of Rotary Club members during the Boulder Dam decennial event. Note: Boulder Dam was officially renamed Hoover Dam in 1947.

An image of visitors standing on a viewpoint platform inside the Hoover Dam powerhouse. Boulder Dam was officially renamed Hoover Dam in 1947.

An image from the power generator floor of visitors standing on a viewpoint platform inside the Hoover Dam powerhouse. Boulder Dam was officially renamed Hoover Dam in 1947.

An image of visitors posing in the gallery leading from the elevator to the Hoover Dam powerhouse. Boulder Dam was officially renamed Hoover Dam in 1947.

A line of women wearing everything from floral printed dresses to white, two-piece bathing suits gather on top of a stage for a Beta Sigma Phi fashion show. A banner above the ladies' heads bares the symbol for the Beta Sigma Phi sorority while onlookers gathered for the event sit below the stage.