OK, not so much the watch but what it was used for?

This is a Reichenberg set into a leather "plate". It looks like it has lived there it's entire life and has an unusual crown position on top of the odd case. The movement is what's surprising: it's incredibly well made with 15j and adjusted to 5 positions.

This doesn't belong to me but to a retired watchmaker and collector. We each have different ideas as to what it was used for (other than to tell the time) and I said I'd share a few photos online to see if anyone could come up with something definitive.

I don't want to share our ideas just yet in case we send some of you off in the wrong direction but I will happily post those ideas in a few hours or so ... assuming no-one comes up with the answer immediately?

 

Swiss made car clock. in the early days of motoring clocks were an aftermarket option.

Looks to have been fitted out a travel clock of some sort.

I'm interested in the "M" stamped on the movement, although I've no proof I once heard that the British military authorities did this at one time.

Perhaps an early attempt at an aircraft clock then?

 

That's the owner's thought ... although he believed it may have been worn on the pilot's hip or thigh.

 

I second the early car or aeroplane clock. Rather than being worn on the thigh though, I think it was probably meant to be hung from the instrument panel.