Before the gold could be extracted, the rock was turned to powder. Depending on the size of the steel balls inside the mill, the rock would be reduced to a certain size. So, multiple mills were usually used in stages.
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A small bunker and blast wall between shell-loading buildings would have provided shelter during disasters, such as tornados, accidental explosions, and perhaps even enemy attacks.
Different doors for different vehicles, I would guess. White Pine Mine used tire-based vehicles, rather than track-based, making it pretty different than other mines I’ve been to.
This picture shows all three areas of the substation. In the foreground is the transformer room, the tallest space. The darker room in the middle is the motor generator room. The room at the end through the door is the control room and office area.
An automatically closing door, in case of fire or flood in the engine compartment.
Fire buckets did not have flat bottoms so they could never be used for other buckety tasks, and were thus always handy in an actual fire.
The top floor of the Meal Storage Elevator.
This rod mill (?) was made in Denver Colorado at a factory now buried by condos. #justdenverthings
Dominion was acquired by UGG, which designated the elevator ‘M’. Their offices still have safety signage.
These copulas made the iron for casting.