Mr. Lanchester proposed the completely different arrangement shown
to the right. His aim was to avoid the engagedisengage procedure by using
an allgeared, constantly enmeshed, fullfledged differential. But to satisfy
the specification given in the Sung Shih
many "misprints" (e.g. number of gears, total number of teeth) have to
be assumed.
Another problem would be accuracy: It is left as an exercise to the reader to calculate the directional deviation resulting from a mismatch of only one percent in the diameters of the road wheels. 
(click for details)

If, for instance, the lefthand roadwheel moves faster than the right,
as on a westward turn, B will move while B_{1}, B_{2} will
be almost stationary, and C will be turning while C_{1} will be
almost at rest. Hence D, D_{1} will react to precisely the same
extent but in the opposite direction. They will then stay put, though C,
C_{1} will resume their mutually opposite regular motion until
further relative change of the roadwheel velocities occurs.