The drivers reversing lever does not operate the reversing gear directly. Instead it operates via a Melling’s  reversing engine.  This is located below floor level just at the rear of the drum.    It is steam operated with water as the locking fluid and is believed to be the reverser  fitted to the Worsley Mesnes winder referred to by J.C.B Hendy in 1891.   There may have been an earlier reversing arrangement, however, since Melling did not patent his reversing engine until 1890.

Reversing-engine schematic

North winder reversing-engine linkage and operating shafts