Diameter of drivers 48 inches. TRUCK. TWO-WHEELED, WITH SWING BOLSTER AND RADIUS-BAR. Diameter of wheels 24 inches. WHEEL-BASE. Total wheel-base 13 ft. 8-1/2 inches. Rigid " 6 ft. 6 inches. TENDER. ON FOUR WHEELS, OR TWO FOUR-WHEELED TRUCKS. Capacity of tank 1200 to 1600 gallons. WEIGHT OF ENGINE IN WORKING ORDER. On drivers 38,000 pounds. On truck 6,000 " ------ Total weight of engine, about 44,000 " LOAD. IN ADDITION TO ENGINE AND TENDER. On a level 865 gross tons. " 20 ft. grade 400 " " " 40 " 255 " " " 60 " 180 " " " 80 " 140 " " " 100 " 110 " " DIVISION V. SWITCHING ENGINES WITH SEPARATE TENDERS. CLASS 15-1/2 C. General Design Illustrated by Print on Page 94. CYLINDERS. Diameter of cylinders 15 inches. Length of stroke 22 " DRIVING-WHEELS. Diameter of drivers 48 to 54 inches. TRUCK. TWO-WHEELED, WITH SWING BOLSTER AND RADIUS-BAR. Diameter of wheels 24 inches. WHEEL-BASE. Total wheel-base 14 ft. 9 inches. Rigid " (distance between driving-wheel centres) 7 ft. TENDER. ON TWO FOUR-WHEELED TRUCKS. Capacity of tank 1600 gallons. WEIGHT OF ENGINE IN WORKING ORDER. On drivers 44,000 pounds. On truck 6,000 " ------ Total weight of engine, about 50,000 " LOAD. IN ADDITION TO ENGINE AND TENDER. On a level 1060 gross tons. " 20 ft. grade 495 " " " 40 " 315 " " " 60 " 230 " " " 80 " 170 " " " 100 " 135 " " [Illustration: Locomotive.] DIVISION V. SWITCHING ENGINES WITH SEPARATE TENDERS. CLASS 21 D. General Design Illustrated by Print on Page 100. CYLINDERS.