Hoisting Engines and Hoist Houses
Mines in Butte employed a wide variety of hoisting mechanisms over the decades. By the 1930s, the most common hoisting engine was powered by an electric motor. The electric hoist at the Orphan Girl mine, World Museum of Mining, is the most easily accessible hoisting engine on the Butte Hill.
Tours of the interiors of other hoist houses may occasionally be arranged, including the compressed air hoists (formerly steam) at the Original and the Steward, and the electric hoists at the Anselmo and Mountain Consolidated.
The simplest form of mining is the excavation of mineral on the Earth’s surface, but sometimes the mineral being sought is deep enough that it is not practical to get to it by digging a large hole in the ground all the way down to the ore body. An alternative is to dig a shaft, like a well, that allows miners to descend to the level where the ore or other desired mineral can be broken free and then hoisted to the surface. To hoist buckets of ore from the mine, early shaft mines employed a windlass (hand-cranked winding drum) placed directly over the shaft, similar to that employed to lift a bucket of water from a well. An early improvement was the horse whim, a drum for winding the rope that was powered by one or more horses walking in a circle around the drum. That contraption was too large to be placed directly over a shaft, so it had to be set on the ground next to the shaft. In order that a rope could be extended down the shaft for hoisting ore, it had to be run over the top of a grooved pulley wheel (called a sheave) and then run to the whim next to the shaft for winding. The simple structure supporting the sheave, A-frame or otherwise, was the beginning of the modern headframe. Such arrangements go back more than 500 years in Europe.
In the years and centuries before Butte mining, ore was hoisted from shafts in buckets, and miners descended into mines either by ladder or (unsafely) in the buckets. By the time shaft mining began in Butte, a new “vehicle,” called a cage, was standard in the shaft. It was a platform on which miners could stand to ride down or up the shaft and onto which miners could place a small ore car filled with ore to be hoisted. The ore cars were run along tracks underground to haul ore and waste rock from the working face of the mine to the shaft. As the capacity of hoist engines increased, the mining industry developed a container like a giant bucket, called a skip, that could hoist a larger volume of ore than a small ore car could hoist. Cages were still used to lower miners and materials (like tools and mine timbers) into the mine, but early cages had little protection for miners. In 1897, the Montana legislature passed a bill requiring safety bonnets and sides on all cages in shafts deeper than 300 feet, which included most of the big mines in Butte.
Steam power increased the speed and hoisting capacity of the mine. When steam-powered hoisting began in Butte in the 1870s, the boilers, steam engines, and headframes were small enough that they could all be housed within a single timber-framed building. As mine production increased, however, the size of steam-powered hoisting engines grew, as did the activities that had to be conducted around the collar of the shaft and, in time, a new configuration arose, with the taller, unenclosed headframe standing over the shaft, and the hoisting engine housed in a free-standing industrial building adjacent to the headframe and shaft. The large hoisting engines in Butte grew to have two side-by-side drums, one overshot and one undershot. When the drums operated in tandem, that allowed for the cable on one drum to be let out while the other was wound up. That in turn allowed the weight of the cable and skip of one drum to counterbalance the weight of the cable and skip on the other drum, thereby reducing the load that the engine had to lift. The surviving hoist houses in Butte are all industrial buildings built either of brick or of steel frame with corrugated steel siding. They have windows for daylighting of the interior, but the windows did not give the hoist operator a view of the mineshaft. Miners underground, surface workers, and the hoist operator communicated with each other by a system of bells.
In the early twentieth century, the Butte mines began to modify their steam hoists to be powered by compressed air, and then they converted to electric hoists.
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