Page:Popular Science Monthly Volume 12.djvu/292

278 The fire-box, N N, is of steel, six feet two inches long outside, 3 feet wide, and five feet four inches high. The tubes, O O, are of iron, 142 in number, 2 inches diameter, and eleven feet seven inches long. The steam-dome, R, is thirty inches outside diameter, the smoke-stack



p, 14 inches. The feed-water is supplied by one pump, h, of 2½ inches diameter and two feet stroke, and by a No. 8 Giffard injector. The valves, T, are 16 inches wide by 8 inches long, and have five inches travel. The steam-ports are 15 inches wide and 1 inch long, and the exhaust-port 15 by 2 inches. The lap of the