Archival objects in this container: Trimming inside of diversion tunnel: photographic print and negative, approximately 1932 to 1933 Constructing diversion tunnel from upstream end: photographic print, approximately 1932 to 1933 Outside of diversion tunnel, displays side walls inside: photographic print, approximately 1932 to 1933 Forming concrete liner in diversion tunnel: photographic print and negative, approximately 1932 Diversion tunnel partially finished with concrete liner: photographic print, approximately 1932 to 1933 Diversion tunnel no. 3 nearly completed: photographic print, 1932 Exterior of diversion tunnel construction: photographic print, approximately 1932 to 1933 Diversion tunnels in use while under construction: photographic print, approximately 1933 to 1934 Lower diversion tunnel exits on Nevada side: photographic print, approximately 1933 to 1934 Diversion tunnels and service bridge: photographic print, approximately 1933 to 1934 Diverting the river, Arizona side, tunnel no. 3: photographic print, approximately 1933 to 1934 Site of Arizona spillway: photographic print, approximately 1933 to 1934 Spillway with road installed: photographic print, approximately 1934 to 1939 Spillway overflowing: photographic print, approximately 1934 to 1939 Bottom of spillway: photographic print, approximately 1934 to 1939 Mule on road to power substation: photographic print, approximately 1930 to 1939 Road near dam power substation: photographic print, approximately 1930 to 1939 Beginning of construction for Nevada substation: photographic print and negative, approximately 1932 Building site of Nevada substation with air compressor in use: photographic print and negative, approximately 1932 Power substation with workers' tents in background: photographic print and negative, approximately 1934 to 1935 Boat landing, three miles upstream from dam: photographic print and negative, approximately 1930 to 1939 Diagram of drill holes: photographic print, approximately 1930 to 1931 Engineer's rendering of Hoover Dam project: photographic print, approximately 1930 to 1931 Artist's conception of the completed Hoover Dam: photographic print, approximately 1930 to 1931 Burned boat operated by Ray Cutright: photographic print, 1931