This illustration, made at Gold Hill, Nevada, in 1876, shows a sectional view of a mine, highlighting the square-set timber method. Note also the tunnels, incline, cooling-off room, blower, and air shaft, along with a collection of miner’s tools. Mines like this one honeycombed the hills of Gold City and neighboring Virginia City on the Comstock Lode in Nevada. University of California at Berkeley, Bancroft Library.