"1506 A blast on the cableway bench excavation, on the Arizona side, above the damsite. Picture taken from lower portal of Railroad Tunnel No. 1. August 24th, 1932.
1507 Huge billows of rock and dust pour over the canyon rim and descend to the river below. August 24th, 1932.
1457 A picture of a blast at the same place shown above, taken from directly opposite, on the Black Canyon Highway.
August 16th, 1932.
1456 Blast on the Arizona intake tower excavation, which has filled the canyon with smoke and dust. Upper steel suspension bridge shown in the background. August 16th, 1932."