Workers on a “Jumbo Rig”at the Hoover Dam, 1930s
Share the History Love... Before the Hoover Dam could be built the Colorado River had to be diverted through tunnels. This piece of equipment, named a Jumbo Rig, was designed to speed up the tunnel drilling process. Built on the back of a 10-ton truck, 24 to 30 drills could be operated at once. Share [...]
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