Twelve-inch turret carrying two forty-five caliber twelve-inch guns for the U. S. Navy. These guns can be loaded at any angle of elevation or azimuth or while in motion. The turret is equipped with a broken or double hoist. The lower hoist supplying ammunition from the magazine to an upper handling room immediately below, and revolving with, the turret pan. This makes the upper or gun hoist shorter and increases the speed of ammunition service, besides interposing two fireproof bulkheads between the guns and the magazine handling room. NICKEL STEEL FIELD RING FORGED WITHOUT WELD FOR A 5,000-HORSE-POWER DYNAMO. (See page 425.) Forged dimensions: outside diameter, 141 inches; inside diameter, 131 inches; width, 51 inches. Rough machined dimensions: outside diameter, 139-3/8 inches; inside diameter, 130 inches; width, 50-3/4 inches; weight, 28,840 pounds. Average physical properties shown in United States Standard test bar taken from full-sized prolongation of end of forging: Elastic limit, 53,560 pounds per square inch. Elongation, 27.05 per cent. TURRET FOR TWO TWELVE-INCH GUNS FOR UNITED STATES BATTLESHIP “ALABAMA.” (See page 426.) Balanced type. Thickness of inclined plate, 14 inches; of side plates, 10 inches. Height of side plates, 7 feet. Largest diameter of turret, 393 inches. Weight of turret, 192.41 tons. CONNING TOWER AND ENTRANCE SHIELD FOR UNITED STATES BATTLESHIP “MASSACHUSETTS.” (See page 426.) Conning tower, one piece hollow forging, nickel steel, oil tempered. Thickness of walls, 10 inches. Inside diameter, 83 inches. Height, 82-1/2 inches. Top plate, nickel steel, oil-tempered, 1-1/2 inches thick. Shield, face-hardened nickel steel, 10 inches thick, 66 inches high. [Illustration: SAFE DEPOSIT ARMOR PLATE VAULT Size, 42 feet 6 inches by 24 feet 6 inches by 9 feet 6 inches high; weight, 450 gross tons. _Courtesy of the Bethlehem Steel Co._] [Illustration: FRONT DOOR, WITH TIME LOCK, FOR ARMOR PLATE SAFE DEPOSIT VAULT Thickness of front door plate, 12-1/2 inches; weight of door plate, 12,000 pounds. _Courtesy of the Bethlehem Steel Co._] [Illustration: _Reproduced by permission of the Philadelphia Museums._ CASTING PIG IRON Molten iron from the blast furnace in the rear is allowed to flow out on this molding floor in which the shape of the “pig” is molded in the sand. After cooling, the pigs are broken apart and stored.] [Illustration: _Courtesy of Indiana Steel Co._ OPEN-HEARTH FURNACES Iron is converted into steel by the basic or open-hearth method in the furnaces shown here. The 100-ton ladles are in position at the tapping side of the furnaces to receive the molten steel.] [Illustration: _Reproduced by permission of the Philadelphia Museums._ POURING STEEL INTO MOLDS