"# 414 Shovel being transported across the river on
a barge to commence the operations of enlarging the tunnels from their twelve by twelve topheadings, shown in the picture, to their full diameter. October 27th, 1931.
# 597 Same as # 414. Tunnel # 4 has been enlarged
and driven approximately fifty feet. First round has been fired in Portral No. 3. The tunnel near the top of the cliff contains the
anchorage for the cable-way from rim to rim. October 27th, 1931.
# 412 View of the upper portals of Diversion Tunnels
Nos. 1 and 2 on the Nevada side. Picture taken from across the river. Tunnel portal3 are totally obscured by scaling operations from above. October 27th, 1931.
# 615 Same as No. 412. Tunnel No. 2 has been enlarged
and driven approximately seventy-five feet. Tunnel No. 1 still obstructed by scaling operations. Note the cable-way tower on the canyon wall, also the carriage with skip attached in mid-air. November 29th, 1931."