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28 THE MarRINE REVIEW MACHINERY AT THE NEW ROYAL NAVAL COL- LEGE, DARTMOUTH. : A short time ago the new Naval College at Dartmouth, for the training of junior naval officers under the new system, was opened. As necessary to this system a large t ; ! usual admiralty practice for high-speed engines. The crank shaft is of steel, in one solid forging, the bed-plate being of cast iron of strong section. Metallic packing of the "combination" type is fitted to the piston-rods and slide-rod glands. To ensure steadiness of running a large, MARINE ENGINE AT THE ROYAL NAVAL COLLEGE, DARTMOUTH. and valuable collection of tools and plant has been laid down in the workshops for the teaching of practical en- gineering. In addition to this, and for the purpose of instructing the young officers in the practical working of the steam engine, a triple-expansion engine, with inde- pendent surface condenser, air and circulating pumps, and all necessary tanks, pipes, etc., for measuring the water consumption under different circumstances, has been in- stalled in the engine-house. The triple-expansion engine, is of the ordinary vertical marine type, without reversing gear. The cylinders are carried by four turned and pol- ished steel columns in front, and three cast iron columns of strong Section at the back. They are 91% in., 1414 in., and 23 in. in diameter respectively, with a stroke of 15 in., the high-pressure cylinder being fitted with piston slide valve, and arranged between the intermediate and low- pressure cylinders. This arrangement has been adopted in order to give easy access to the intermediate and low pressure slide valves, as the engine will be used for the instruction of the cadets. The engine was required to develop 120 H. P. when running at about 120 revolutions per minute, with steam having a boiler pressure 140 lbs. per square inch; but, in order to have ample margin of strength, the machinery was designed for a working pres- sure of 185 Ibs. per square inch. The scantlings, bearing surfaces, etc., are, therefore, larger than are actually re- quired, a point of considerable advantage when it is remembered that this engine will be looked after by the young officers, and that it will be opened out, overhauled, adjusted, etc., etc., by them as part of their training. The pistons are of stamped steel of the coned type, machined all over, the high-pressure and intermediate-pressure pis- tons being fitted with hard gun-metal Ramsbottom pack- ing rings, and the low-pressure piston with ordinary dou- ble cast iron spring rings. The piston-rods are of forged heavy cast iron fly-wheel 5 ft. 6 in. in diameter and 16 in. wide on the face, carried by a separate shaft supported INDEPENDENT VERTICAL AIR PUMP by two. plummer blocks, and coupled direct to the crank shaft, has been provided. The face of this fly-wheel is utilized to drive a dynamo by means of a belt 12 in. wide. steel, solid with the crosshead, the slippers being of gun- metal lined with white metal, in conformity with the