An auxiliary piston reciprocates in the other cylinder and is driven in timed relation to the working piston by means of a cam affixed to the crankshaft and {HEAD ~ a cam follower} attached to {TAIL ~ a connecting rod} 
attached to
An auxiliary piston reciprocates in the other cylinder and is driven in timed relation to the working piston by means of a cam affixed to the crankshaft and { HEAD ~ a cam follower } attached to { TAIL ~ a connecting rod }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL