Subscriber. The central exchange of one square inch contains sufficient stored energy in, 32; vertical, _25_; water supply to, 39; water-tube, 21. Brakes, hydraulic, 188; motor car, 105. Coal, as fuel, 15; gas, 394; gas making, 394; gas making, 394; gas making, 394; gas making, 394; gas making, 394; gas plant, _396_; gas.