united states mine rescue association Mine Disasters in the United States
Leonard Mine Hoist Accident
Butte, Montana April 23, 1913 No. Killed - 5
The engineer started to lower the east cage from the surface to the 60-foot level using the hoisting-engine brake with the reel unclutched; it is believed that the rod connecting the steam brake-operating device with the controlling lever broke, and the brake failed to grip.
The loose reel gained such speed that when the engineer attempted to stop it by throwing in the clutch, the latter broke, and the reel continued to accelerate until it burst. Flying pieces broke the connections on the west brake, and the west cage at the 1,400-foot level began to drop just as the east cage crashed past.
Four men on the east cage were killed instantly when the cage hit the shaft bulkhead at the 2,200-foot level. The bursting reel wrecked the hoist room, and one man at the surface was killed by flying fragments.
Eight men on the west cage were injured seriously, but, remarkably enough, none were killed.
Historical Summary of Mine Disasters in the United States, Volume III