During the gold rush, when the easy surface gold (placer gold) ran out, hard rock mining was developed to follow the gold veins deep into the earth. The Hoist House at a gold mine housed the machinery that transported men deep into the mines, and pulled the ore cars and skips laden with gold-bearing ore to the surface for processing. The cable going through the wall from the hoist went over a headframe wheel and then attached to an ore skip. The hoist operator knew when to stop and start the hoist based on a series of bell signals from workers deep in the mine.
The hoist operator was one of the most trusted, experienced, and respected workers in a mining operation. The lives of his fellow miners were in his hands. Using only a system of bells, he could stop and start the ore cars at any level in the mine shaft—sometimes over a mile below the surface.