Two-stroke vee-twin engine with pumping cylinders

Fig. 205 Two-stroke twin-cylinder engine with separate pumping cylinders.
A twin cylinder two-stroke engine, using another pair of cylinders (four in all) to provide compression. The more common modern method is to use the crankcase for the same purpose.
Although described in the original caption as a "vee twin", this is more like a parallel twin. The "vee" aspect is how the pumping cylinders form the vee.
Scans from 'The Book of the Motor Car', Rankin Kennedy C.E., 1912

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