The Lentz steam engine was a distinctive part of the industrial history of America’s heartland, one of the engines that powered electricity generation and machinery in factories and municipalities around the world. Built by the Erie City Iron Works in Erie, Pennsylvania, in 1925, this engine generated electricity for the Municipal Light of Denver, Colorado, until the American Excelsior Company of Rice Lake, Wisconsin, purchased it in 1946. After installation there, it powered the plant’s lights and small motors and, through a line shaft, ran all of the production machinery. Steam for the engine came from a boiler fueled by wood scrap, making the operation very efficient. The mill operated 20 hours a day, 5 days a week, producing excelsior that was baled and shipped by mail across the U.S. The unit was taken out of service in 1976. This Lentz balanced poppet valve steam engine weighs 16 tons and measures 19 ft. wide and 21 ft. long. Its flywheel is 12 ft. in diameter. It is a single-cylinder engine with a 19-inch bore and a 21-inch stroke, producing 350 horsepower and operating at 200 RPM.