The historic powerhouses of the Sierras have been powering much of California's growth for the past hundred years or so. Located in canyons where water can be dropped thousands of feet from ridges above, they were California's first source of electrical power. The oldest powerhouses were built by survivors of the original gold rush, who turned metalworking and pipe-fitting skills to the task of generating electricity. The resulting machines were curious amalgamations of steam valves, riveted pipes, waterwheels, and rudimentary electrical devices imported from the East Coast. These views show how miners chipped out a small ledge on a granite cliff hundreds of feet below Spaulding Lake dam to create an anchor point for a powerhouse that seems embedded in the rock itself. They also celebrate the genius of mining-camp tinkerer Lester Pelton, who, in 1880, invented a more efficient waterwheel capable of spinning a generator shaft at high speed. His invention bore his name, and the basic design is used to this day throughout the world.