A friend sent these pictures to me if their recent acquisition saying;
"Hi David,
Ever seen one of these? It's a New Haven clock that's housed in a very rugged brass housing. To wind it, you release the pin on the back and rotate the entire front housing of the case. When it's wound, the pin slips in place, locking it "12:00 up". It's seems to be built too heavy for an airplane. Maybe for a bus, truck, trolley?
It's good for a few ticks now, but the mainspring is broken."

It looks to me to possibly being a "running time" clock, for a Locomotive, or machine or what? Anybody have any thoughts what it is?