Speed Bore of Cylinder Crank Shaft Height Breadth Diam. Wide Diameter Wide ft. in. ft. in. C. q. in. •4 3 2 2 3 6 0 5 4 2 2 in. Revs. in. in. in. HIGH-SPEED ELECTRIC LIGHT ENGINES (SINGLE CYLINDER) 101 Diameter Wide ft. in. in. Revs. in. in. 3 6 250 8 12 250 It is interesting to note that the 1879 catalogue from which the foregoing table is taken contains the following: Tenders for larger sizes and for "compound engines" on application.' Robey & Co. (Limited), Lincoln' On the expiration of the Otto' patent Messrs. Robey & Co. decided to manufacture gas engines, using the 'Otto' cycle, with various structural modifications introduced by the author in 1890. Figs. 17, 18, and 19 being a section, plan, and external elevation of an engine capable of developing 24 B.H.P., represent the characteristic features of the valve arrangements of all sizes. The cylinder of this engine is 11 inches diameter and the stroke 18 inches. It will be seen that the cylinder A and bed are in one casting, the water jacket B coming well up to the end of the liner C, which is forced in from the back, and made tight by metallic joints only, and kept in position by the combustion chamber F, which is bolted to the end of the cylinder, having a projection fitting into a recess formed by making the liner a little shorter than the cylinder. The whole of the combustion chamber is water-jacketed, G, although not in communication with the main jacket B, and has a separate inlet H and outlet I; D and E being the supply and outlet to the cylinder jacket, the bridge pieces connecting them with the main supply and outlet pipes. By arranging the areas of the relative openings proportionate to the needs of the combustion chamber and main jacket, a most efficient circulation is obtained. The air valve J and exhaust valve K being in the direct line of the impulse greatly facilitate both the inlet of the charge and expulsion of the products of the combustion; and as the gas entering at L through the channel M meets the inrushing air drawn from the air-silencing chamber O (placed inside the base N) through the pipe P, a pure mixture is ensured at the nearest point of ignition-viz. the igniting port Q, which being a very short one and on the direct line of engine, ensures a very reliable ignition without a timing valve. R is the gas inlet from the main gas cock L, used for the |