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[[preprinted]] 22 AVIATION May, 1911 [[left column]] two rings. The gudgeon pin made from case hardening nickel chrome steel is held in the usual way. The valves are of 3 per cent nickel steel of the ordinary mushroom type, held in a cast iron seat, screwed into the cylinder head, and can be easily removed. The valve gear levers and tapits are made from special case hardened steel, and drilled out wherever possible, machined all over. The cam gear consists of a concentric cam, mounted on a phosphor bronze bush, runs in the same direction as the engine, and is driven by one pinion, which is mounted on ball bearings. This pinion is driven from a wheel on the reducing gear. The oiling system of the engine is of the forced feed into the center of the crank shaft where it is acted upon by centrifugal force and carried into the crank pin, lubricating the main connecting rod bearing. It then runs to all the pins linking up the other connecting rods to the gudgeon pins. The oil thrown out from all rotating joints is sufficient to lubricate all cylinders equally. The main bearings being ball bearings receive sufficient lubrication from oil thrown off by the crank pin. Any excess of oil, which is very little, owing to the special pump arrangement, runs down into the bottom of the engine, and so up through the carburetor into the valves and tops of the cylinders, thus the inlet and the exhaust valve stems, and all the upper part of the cylinders are well lubricated. It will be gathered from this fact that the original supply of oil is very small and there is no waste, hence the great economy. The reciprocating pumps, which are in duplicate, are contained in a rectangular box running at 1-30th of the crank shaft speed, deliver oil through a special form of piston valve into a glass sight feed tube, and thence through a flexible pipe into the crank shaft. The oil consumption does not exceed 1.1 pint per hour The ignition is of the Bosch High [[/left column]] [[right column]] Tension Magneto system, consisting of one magneto supplying current to one distributor mounted concentric with the crank shaft. This distributor is placed in such a position that it cannot be affected by moisture. All wires to the spark plugs are perfectly straight and radial. A reducing gear is arranged between the crank shaft of the engine and the boss of the propeller. By using this gear the following advantages are obtained: The propeller is run at half the revolutions of the engine, i. e., from 800 to 900 revolutions per minute. This enables them to use a larger and more efficient propeller with a small and lighter engine without diminishing the power. The propeller by being run at half the speed of the engine has less stresses to withstand, and as the engines give seven explosions to one revolution of the propeler, a more even twist is transmitted to the propeller boss. By the use of this gear the combined efficiency of the engine and propeller is greatly increased. It enables us to build a smaller engine for a given power and thus reduces the head resistance. The propeller is not used as a fly wheel. The reducing gear consists of a hardened gear wheel, keyed to the engine shaft; two gear wheels placed on opposite sides with gear into the wheel on the shaft and run at the same speed. Forged solid with the two wheels are two other smaller wheels with less teeth geared into a wheel fixed to the propeller boss. This train of gear wheels gives a total reduction of two to one. The propeller boss is mounted on a hollow steel sleeve fixed to the crank case and runs concentric with the engine. At the end of this sleeve a thrust ball bearing of ample size is secured by two nuts, so that the entire thrust from the propeller is taken direct on this sleeve and not through the crank shaft. The engine can be throttled to run from 190 to 1600 revolutions per minute, and the propeller from 95 to 800 [[/right column]] [[/preprinted]]]]
