Jacob & Co. Five Time Zone

I'd appreciate your help in helping to evaluate this watch. It was my father's, and I believe he would have got it in the early 1960's, though it's possible he got it in the late 50's. It's obviosuly an Admiral, but there are no clearing markings on the back, other than the type of wrench needed to remove the bezel.I've looked on eBay and other sites, including this one, hoping that I could date the watch based on the face markings (even numbers only - odd numbers represented by non-numeric ma........

So a couple of weeks back I decided that I owned too many watches from the "boutique" brands so I decided to sell one. One of the three was a gift from my wife. Can't sell that. One was super inexpensive and very unique (and my wife LOVES that one as much if not more than I do). The third was a gorgeous watch, but the brand has some real odd styles on the horizon, and has newer and similar styles to mine at a lower price point, so it seemed like a no-brainer to try and cash in on that one. ........