Here is in more detail what I mean when I say that this looks like the work of the same engraver. This similarity of the style of engraving and matching serial numbers to me suggests this case was matched at the Longines factory to your movement and made to order for the retailer.
Wow, Seiji - you're the research expert!
Just looked at fonts, position and alignment of the serial in the case - all very much Longines-style. Guess you are perfectly right.
Thanks!
Gerd
Let me guess: Case not made by Longines, but by a fountain pen manufacturer in the US?
Mine was born just a couple of days (hours?) before yours, but somebody slaughtered it for gold 😕
I don't have one of these with a case. There is one on eBay or at least there was one recently. Really hard to find one of these Geo Aggassi or EF Francillion versions with the case. Don't know the story behind why almost none have a case.
Anyways, the point is that the engraver is the same person again. Note the long "R". The engraver is leaving his/her DNA all over these movements and your watch case. Look at the R in Francillion on the movements and the R in your Grove
I like the fact that it's 150 years old and the key wind is awesome to me. Ill probably be spending 5-700 to have it repaired and the crystal and bezel replaced. I know I'm "throwing money away" but I've always wanted a cool old pocket watch. Thankfully I only paid $20 for it