The first monarch 10EE lathes (this illustration is from an operator's  Manual dated April 11, 1941) can be easily distinguished by the round gearbox selector plate with its push/pull/twist handle arrangement.

Massive, imposing and handsome - an early 10EE refurbished by its enthusiastic owner. The version was built during WW2, the dials and name plates being made from brass instead of the usual aluminium, the latter  deemed a strategic material and not to be used unless essential

Thought to be a very early example, this 10EE has a distinctly-different selector box on the face of the headstock: instead of just a dial selector, an additional left-right lever was fitted (on top of the box) this fitment indicating that the machine is a round-dial version of the ELSR Type (electronic lead screw reverse). Instead of an ordinary drum-type electrical reversing switch that function was taken care of by raising or lowering the handle on the top rod, an action that pushed/pulled another rod through the selector with two micro-switches inside. The lever was normally used in the neutral position, but had a left-right setting that somehow affected the ELSR function while threading.