My great Uncle Joe's watch!

My mother recently gave me this watch. It says Eaton on the face which initially led me to believe it was perhaps a quarter century Eaton anniversary watch, but I really don't know. I was just reading someone's submission remarking how long these watches last. Indeed, this one still ticks!

On the back there are only his initials carved very elegantly, JW. There is no cover, and it appears there never was, but there is this attached pocket knife. Can anyone tell me anything about it?

Thanks. Sharon