This figure represent a partial longitudinal
sectional view of a four-stroke engine having a variable volume
combustion chamber with a ratio of 5 between the paired cylinders,
shown in the start-of-travel position of the variably timed transmission,
at the end of the compression phase.
it also shows helical splines mated between
the first and third concentric members, having circular helixes
contrary to those of the helical splines mated between the second
and third concentric members.