New Locomotive Types.

A Wonderful monument to engineering genius is the modern express locomotive. By the Home railways and the great overseas transportation undertakings steady progress is being made in the construction of larger and more powerful steam engines, and notwithstanding electrification's progress it is safe to assert that a long and useful life still lies ahead for the steam-propelled “Iron Horse.”

This year sees some remarkably fine types of express passenger locomotives employed on the group railways of Britain. There is the wonderfully powerful “King George V.” class of engines utilised on the Great Western main line out of Paddington Station, London. These 4-6-0 locomotives have four cylinders, a boiler pressure of 250lb per sq. in., a total heating surface of 2,514 sq. ft., a grate area of 34.3 sq. ft., a tractive effort of 40,300lb., and weigh, with tender, 135 tons 14cwt. Out of King's Cross Station, London, we have enormously heavy trains hauled by the new Doncaster-built “Enterprise” engines. These are 4-6-2 locomotives with three cylinders. They have a boiler pressure of 220lb. per sq. in., a total heating surface of 3,442 sq. ft., a grate area of 41.25 sq. ft., a tractive effort of 36.465lb, and a total weight with tender. 152 tons 11cwt. Then the London, Midland and Scottish Railway gives us a fine example of modern passenger engine design in its “Royal Scot” class of 4-6-0 machines, with three cylinders, a boiler pressure of 250lb per sq. in., a total heating surface of 2,526 sq. ft., a grate area of 31.2 sq. ft., a tractive effort of 33,150lb, and weighing with tender, 127 tons 12cwt. Last, but by no means least, comes the splendid “Lord Nelson” machine of the Southern line, a 4-6-0 engine with four cylinders, boiler pressure 220lb per sq. in., total heating surface 2,365 sq. ft., grate area 33 sq. ft., tractive effort 33,500lb, and total weight, with tender, 140 tons 4cwt.

These outstanding locomotives represent Home railway locomotive design at its best. All have a great deal in common, but differences exist here and there in their design, among which the following may be noted. The Great Western engine has four cylinders with cranks at 180 degrees, giving four exhaust beats per revolution, and is equipped with a high-pressure boiler with narrow firebox. To the “Lord Nelson” of the Southern are fitted four cylinders with cranks at 135 degrees, giving eight exhaust beats per revolution, and here again we have a narrow firebox. The other two engines each have three cylinders with cranks at 120 degrees, giving six exhaust beats per revolution. In the L.M. and S. Locomotive we find a narrow firebox favoured, while the L. and N.E. engine has a larger boiler having a wide firebox. All the machines named are equipped with super-heaters.

Across the Channel, the German railways have always been famed among European lines for employing interesting and powerful locomotive types. Recently the German railways have always have introduced two new classes of locomotives of noteworthy design. One of these is a two-cylinder “Pacific” passenger engine, and the other a two-cylinder “Decapod” freight locomotive.

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The “Pacific” passenger engine has an axle load of 20 tons, and the leading dimensions are as follows:—Cylinder diameter 25 5/8 in., piston stroke 26in., diameter of driving wheels 6ft. 6 3/4in., total wheelbase 40ft. 8 1/4in., grate area 48.4 sq. ft., working pressure 200lb., tractive power 16 1/2 tons, weight in working order 107 1/2 tons. This engine is to be employed on the trans-continental passenger services centred on Berlin. The “Decapod” freight locomotive has been developed as standard for long-distance freight haulage. It has a cylinder diameter of 23 1/2in., piston stroke 26in., diameter of driving wheels 4ft. 7in., wheel base 31ft. 8in., working pressure 200lb., weight in working order 109 1/2 tons, and tractive power 25 1/2 tons. Constructed by the Berliner Maschinenbau A.G., the locomotives named represent the very latest types of high power engines to be employed on the German railways, and come as a noteworthy addition to the long list of efficient haulage machines employed by the European lines in recent years.