No records have come to light that relate the serial numbers of pocket watch cases to dates or grades of cases. Your watch case is gold-filled and was made, as you know, by Joseph Fahys & Co. Welcome to the NAWCC American Pocket Watch Message Board! The s/n is repeated on the frame that holds the movement. The second cover, which reveals the movement, has only "Fahys" & "Montauk," plus the s/n. he went through a period when he inscribed anything of value with that number. Or this could be the last digits of my father's driver's license, now lost in the mists of time. Opening the first cover on the back, you see above the Fahys name, the caduceus, and a hand-scribed number, S11159 or 511159, possibly from the watchmaker who repaired the case. The inside of the dial cover has only the Fahys s/n. The back, which is even more worn, has the shield with (?) a house on a hill, with maybe a further hill with trees in the background. The hinge is broken and has an iffy soldered fix (solder itself is white metal). You can make out an arabesque-like shield on the front with my grandfather's initials, E.C.G. Is there reference online for Fahys serial numbers? Or, does anyone know the date? I'm fairly certain it is contemporaneous with the movement The back covers of the Fahys case have the caduceus and "Montauk" with a s/n 5641773. The movement's s/n, 693279, is apparently 1889. I have my grandfather's Dueber lever-set watch in a Fahys Montauk case.