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This is a bit of a mystery. Case does look to be a match to Nightingale. Nightingale has a center sweep second hand. It doesn't look like subject watch ever had one? Dial has a notch at "6" position, indicating the dial was refinished. Linked watch has an ad from 1942 with matching fully numbered dial. I will agree with the ID noting above discrepancies.
Interesting about the notch at 6. Having had a couple of dials refinished, I have not been apprised of such a marking. I will take another look re sweep second.
I have no clue as to the history of this watch. It was in among a bunch of other movements/watches/parts that I bought from an NAWCC member who got it from the widow of a watchmaker.
The case back is a mystery too. It has a serial number starting with "0" which would match the movement date symbol of "*" for 1940, but it is also stamped "49". And it was stamped very hard. Don't know if I've ever seen one stamped so hard it shows up inside the case back.