emeshed gear 11 and attached eccentric 7 to rotate on crankpin 5 the rotation of eccentric 7 on crankpin 5 causes connecting rod 10 to be raised and lowered upon crankpin 5 and thus to this degree augments the simple harmonic motion resulting from the rotation of the fixed crank radius of crankpin 5 the relative motion induced by rotation of eccentric 7 on crankpin 5 is transferred through connecting rod 9 to piston 10 and thus influences the normal compression and expansion rates of the working fluid above the piston it is also seen that the crank radius varies in a cyclic manner which also influences the rotative effort in a manner which is proportional to the change in the crank radius moment arm for maximum efficiency the moment arm should be extended during the expansion cycle and retracted during the compression cycle turning now to fig2 eccentric 7 and fixedly attached gear 11 can be remounted on crankpin 5 such that it is now adjacent to gear 16 as shown in fig2 in this arrangement gear 12 and gear 15 are therefore correspondingly mounted at the same end of shaft 13 as shown the synergism is the same as that described for fig1 the only difference between the two systems shown is in the fact that all of the gearing is mounted on one side of connecting rod 9 in fig2 while in fig1 the gearing was mounted on both sides of the connecting rod turning now to fig3 which is a detailed drawing of the idler gears showing.