An aerial view from over the spillway bridge of the open valves at Hoover Dam.

This photograph has three images. The first one (0272_0049) shows the No.2 diversion tunnel with floor and side walls concreted during the Hoover Dam Project (Taken by Oakes). The inscription reads "Trucking mud to short hoist above that transfers the mud further in, reinforcing with re-bar where spillway 'intersects' diversion tunnel." The second one (0272_0050) reads, "Big Gamble - using 8 yd. Bucket, dumping mud in small face pour. Notice all that rebar. This is where the dam takes off from the powerhouse. Did this once too often - at a much higher elevation. Cable broke at tail tower, bucket no longer under control. Knocked out the panel and slide down the face of the dam and slowly came to a halt. The doors came open and dumped the mud. Lot of excitement at the pour. Someone noticed a small light down by the bucket. Investigating, they found a bell boy striking matches. He had ridden the bucket all the way down." The third image (0272_0051) reads "View of powerhouse. (x) shows where turbines will be installed." (Bureau of Reclamation photo)

The Las Vegas High Rhythmettes posing at Hoover Dam in Nevada.