I cant seem to find model numbers on the watches or maybe I just do not know what I am supposed to be looking for. Everytime I put in what I think is a number I can never seem to find anything online to it...I was wondering if every watch had a different serial number? Also, the person we got this from said its from about 1910-1920. It was made for Tiffany & Co. by the Longines Watch Co. The number I found was "2515238"....not sure what that number represents. Its an alleman Swiss pocket watch. 0.800 and thats pretty much all I know. Can anyone maybe help identify this Vintage piece?