All About Engines

The Locomotive 257 and the “ Rocket ” won. It weighed only 4J tons, while the modern engine weighs 100 tons. The boiler was 6 ft. long, 40 inches in diameter, and contained twenty-five 3-inch tubes giving a large heating sur face, and enabling steam to be made rapidly. The cylinders were inclined, and the wheels were con- , nected by a coupling-rod so as to increase the grip on the rails. (See Fig. 143, Plate 25.) By the time that the line was opened several engines were ready, but the joy of success was marred by a terrible tragedy. Mr. Huskisson, M.P., a famous statesman, was knocked down and so badly injured that he died the same day. In conveying him to a place where he could receive attention, the “ Northumbrian,” with Stephenson on the footplate, covered a fifteen-minute journey at the rate of thirty-six miles an hour. The sad event secured great publicity for the locomotive, and led perhaps to a greater interest in it than would have been obtained if there had been no mishap. During the next three years improvements were made, and the locomotive rapidly assumed the general form which is so familiar to-day. The cylinders were placed in front, underneath or on each side of the smokebox, and were horizontal or only slightly inclined. The boiler was supplied with a steam dome, in which was placed the valve admitting steam to the cylinders. The greater height of this valve above the surface of the water enabled drier steam to be obtained and thus reduced priming. Apart from these features, there was one outstanding invention