Cecil Hughes designed a strange rotary engine that had six double pistons oscillating on a tilted plate.

“Hughes rotary” (PiP)

“Engine cross-section” (PiP)

-As we see, the double pistons are half-toroidal, with a combustion chamber at each end.

-The ignition is transmitted by fixed poles at the spark plugs in the engine drum.

-Now a view of the real engine appeared in Popsci. We deduce that one end of the engine is fixed to the structure of the vehicle and the other end rotates with the engine barrel.

“Real Hughes rotary engine” (PiP)

-Here this engine is mentioned by the inventor's name, but it is also known as Selwood (see).

“As Selwood, more complete”

-We see the rotor from the previous examples already placed in an external fixed body together with its carburetor.