25,983. Roots, J. D. Dec. 13. Gas and like engines of the continuouscombustion type..A two-strokecycle oil engine is shown in Fig. 1, in which the products of combustion are expelled either by the upward movement of the piston or by air currents, some of the air or products being allowed to remain in the cylinder, after the closing of the exhaust valve, to cushion the movement of. the piston, and to prevent the reduction of temperature of the incoming charge. On the up-stroke of the piston B, air is drawn into the pump chamber D through the valve E, while liquid fuel, entering through a valve-controlled orifice N<4>, N<8>, Fig. 4, flows over a series of plates or perforated disks N<6>, N<7> and carburets the air as it is forced into the combustion chamber G through the valve F during the latter part of the downstroke of the piston. The ignited charges, which are fired at starting by a cartridge inserted in the chamber G, are admitted to the working end of the cylinder through a partly balanced and camactuated valve H. The exhaust valve is operated by a cam which runs in a bath of oil. If preferred, one combustion chamber may serve several cylinders ; or a separate air-pump may supply the air charges. The engine may also be operated by gas.charges which are fed to the pump chamber with the air. To. prevent the bursting of the combustion chamber, it may be wound with wire. When starting, a charge of fuel and air is pumped into the combustion chamber through the nozzle R<2>, R<3>. Reversing; governing; valves and valve-gear.- Reversing is effected by advancing the time of opening of the inlet valve and thus admitting the ignited charge before the completion of the upstroke. The time of opening is adjusted by varying the position of the roller K' through which motion is communicated to the valve-rod K<3>. The roller is mounted on an arm K carried by an eccentric, the sheave of which is adjustedby a spindle L<1>, Fig. 1. The cam I, Fig. 5, is loosely mounted on the cam shaft J, and is driven by a key which engages with the respective ends of the slot I<1>. As the engine reverses, the position of the cam is automatically adjusted by its engagement ,with the end K<2> of the valve-rod. The lift of the .valve H and the time of cut-off are varied by imparting a transverse movement to the roller K<1> through the hand-lever M. The contour of the cam I is shown in Fig. 5, one face Y being used for forward running, and another Z for running in the reverse direction, or vice versa. If preferred, the inlet, valve may be operated by eccentrics. Governing may also be effected by mounting a throttle valve E<2>, Fig. 4, in the air-supply pipe on an extension of the oil-valve spindle N<2> so that both supplies may be regulated simultaneously. If preferred, the spindle L may be. connected to the spindles of the air and fuel valves.