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Europe's Most Powerful Engine.

On the Continent of Europe an especially interesting steam locomotive recently produced is a high-pressure engine built for the German Railways by the Berlin Maschinenbau A.G. In general outline this locomotive resembles the standard 4—6—2 express passenger locomotives of the German Railways, the principal variations being the introduction of three cylinders and the modification of these and of their valves so as to render them adapted for ultra-high steam pressures. The boiler, however, embodies the principles evolved by the late Professor S. Loffter, and is an entire departure from previous practice. Two of the three cylinders take the form of high-pressure cylinders outside the frames, the other being an inside low-pressure cylinder driving the leading axle. The high-pressure cylinders are of eight and three-quarter inches diameter, and the low pressure cylinder has a diameter, of twenty-four inches. All the cylinders have a twenty-six inch stroke. The diameter of the driving wheels is 6ft. 6¾ in., diameter of the bogie wheels 2ft. 9½ in., and the diameter of the trailing wheels 4ft. 0½ in. The weight of the engine, empty, is 111½ tons.

The Loffter system claims to provide all the thermal advantages of high pressure superheated steam without danger and excessive cost of construction. It is said to retain the many valuable mechanical properties of the conventional locomotive, inasmuch as the motive mechanism is of the reciprocating type. Also, it claims to solve the problem of boiler scale, the water being vaporised and steam generated in a high-pressure boiler and drum. wherein there are found no flue gases or products of combustion. Steam pressures employed vary from 215lb. per sq. in. in the low-pressure boiler to as high as 1,700lb. per sq. in. in the high-pressure boiler. The machine is of a somewhat complicated nature, but already it is understood that trial runs have shown the locomotive to be capable of high speeds, running on 50 per cent. less coal fuel than the conventional type of express passenger engine.