With two tractors and six men, one California lumber company has reduce and delivered, to the pond at the mill, 40,000 ft of lumber a day. From its top, or from the highest of one other high tree, a gang of males, with assistance from the tractor's winches, runs a steel cable to a different tree, in all probability half a mile away down the hill. The automobiles will slide down and climb out at a nearly uniform speed of 600 feet a minute.