In the late 1880s, logging around the Castle Crags area was booming, and steam donkeys were used to haul heavy logs from cutting sites to milling areas. A steam donkey consisted of a boiler and steam hoisting engine mounted on a wooden sled. The engine turned metal drums around which cable was wrapped to pull heavy loads through the woods. These machines could haul logs, themselves, and other heavy equipment from place to place, and because they were ideal for steep hillsides they were quickly adopted by California’s logging industry. Highly skilled donkey punchers were seldom out of work. This boiler was once owned by M.A. Burns Lumber Company, which went out of business in 1916, and it was discovered unexpectedly by park staff in 1994.