Engineering Wonders of the World
Volume I

Fig. 42.—ARTICULATED COMPOUND LOCOMOTIVE, HEDJAZ RAILWAY (ARABIA). Cylinders, 12f inches and 20 inches by 22 inches. Coupled wheels, 3 feet 4J inches. Fleating surface, 1,780 square feet. Weight, 51f tons. Gauge, 3 feet 6 inches. This is a good example of advanced Continental practice. The leading wheels are only four-coupled, with a pair of small carrying wheels, so that the engine is a combined four-coupled and six-coupled loco- motive, an unusual feature in articulated engines. Built by Henschel and Sohn of Cassel, Germany. Fig. 43.—ARTICULATED LOCOMOTIVE FOR THE PEKIN-KALOAN RAILWAY OF NORTH CHINA. Cylinders, 18 inches and 28f inches by 28 inches. Coupled wheels, 4 feet 3 inches. Heating surface, 2,591 square feet. Weight, 96 tons. This engine is interesting as being the first Mallet Articulated built in this country. The makers are the North British Locomotive Company. This type was designed to handle heavy trains on gradients of 1 in 30 and on curves of 500 feet radius. It is generally considered that the first articu- lated engines were those built a good many years ago for working one of the severe lines of the Austrian State Railways. One of these engines had two boilers carried on one frame, and two similar sets of four-coupled wheels with their own cylinders and mechanism, each mounted on a frame pivotally connected to the main frame, one under each boiler. The other engines had the wheels arranged in two sets, one pivoted, and some wonderfully com- plicated chain and lever gearing, so that the cylinders could drive one set of wheels directly, the other indirectly.