Archival objects in this container: One of the Mack trucks in front of the upper portal of Diversion Tunnel Number 2. Note the steel canopies over the driver's heads on all the trucks: photographic print, 1932 January 28 Bucyrus shovel working on road to lower end of Tunnels Number 1 and Number 2: photographic print, 1931 May 02 Looking out of the lower portal of Diversion Tunnel Number 2: photographic print, 1932 January 25 A flashlight photograph of the interior of one of the diversion tunnels. The drilling jumbo is working at the tunnel face: photographic print, 1932 January 28 One of the drilling jumbos ready for action on the upper portal of Diversion Tunnel Number 1: photographic print, 1932 January 28 A telephoto view of the muck disposal area on the Arizona side, below the lower portals of Diversion Tunnels Number 3 and Number 4: photographic print, 1932 January 19 Drilling jumbos mounted on the back of a truck for lower portal Number 4. This first wood-frame jumbo was experimental, later they were steel pipe: photographic print, 1931 September 26 Six Companies shovel operation at lower portal Number 4, Arizona side of Black Canyon: photographic print, 1931 September 28 Lower portal Number 4, Arizona side of Black Canyon: photographic print, 1931 September 25 Government pumping plant at the Colorado River in Black Canyon: photographic print, 1931 August 07 Frigidaire drinking water and water-cooling plant at compressor plant Number 2, Arizona side of Black Canyon: photographic print, 1931 August 09 Looking up from a point below the lower portals, showing the government pumping plant (lower left), the Six Companies' compressor plant (middle left), the location of the lower portals, and the highway loop above the canyon wall (upper center): photographic print, 1931 July 30 A Six Companies freight barge at the lower portals: photographic print, 1931 September 26 Marion electric shovel directly over the dam site during construction of the government highway: photographic print, 1931 September 26 Bucyrus-Erie shovel excavation for Site Number 3 compressor plant: photographic print, 1931 June 02 Bucyrus-Erie shovel excavation for Site Number 3 compressor plant: photographic print, 1931 June 02 Shovel excavation of a blasted rock cut along the edge of Black Canyon: photographic print, 1931 June 02 Six Companies railroad grade below Cape Horn, Black Canyon: photographic print, 1931 August 09 Upper portal of the Six Companies railroad tunnel Number 1: photographic print, 1931 August 09 Six Companies railroad grade above railroad tunnel Number 1 showing the proposed location of the "low-mix" concrete mixing plant: photographic print, 1931 August 09 Boat landing at railroad tunnel Number 1 and the catwalk to the Arizona side of Black Canyon: photographic print, 1931 August 09 Duplicate of photographic prints: photographic negatives, approximately 1932 to 1934
