Very sweet piece. Great history. Thanks for sharing.
When you say it doesn't say Ball anywhere - you mean inside the case right?
My super limited scope for these was that the majority were 17 jewel watches and there were a few higher jewel counts made up to 21.
Is this the case and how rare and expensive do they go?
So, a couple of different things.
This is an 1890s watch, and it was common practice at the time for the end buyer to purchase the case and movement separately, or truth be told more often the jeweler/inspector or whoever would case them up on display from their inventory of cases and movements, and would sell a pre-made combination or swap things around to the buyer's taste(i.e. some might want a fancy case and don't really care about the movement, a railroader needed a high quality movement but wanted a simple or inexpensive case. Maybe someone else would want it all.
Later on, it became common to case movements at the factory, and Ball was no exception. This one, IIRC, is in a Keystone 20 year gold filled case, so nothing particularly special.
I showed a couple of close ups for a reason. If you look closely at the logo on the dial it says "Trademark Official RR Standard Wm. Kendrick's Sons Louisville". A typical Ball dial has an identically styled logo but says "Ball Watch Company Cleveland" where this one is marked Kendick Louisville. Similarly, the movement on this one carries the marking "Wm. Kendrick's Sons Louisville KY." A standard 18 size Ball-Hamilton would be marked "Ball Watch Company Cleveland" in this spot. This watch is not marked "Ball" anywhere on it, even though from a foot away you likely wouldn't notice anything unusual about it if you've owned/looked at 18 size Ball Hamiltons(they're one of the less expensive Ball Official Railroad Standard watches).
As for the jewel count-Ball largely followed industry trends. In the 1890s, Ball was a loud voice saying 17 was plenty and there are advertisements he put out claiming more didin't do anything. Cap jewels on the escape wheel and pallet fork DO have less overall friction, allow better adjustment and control of endshake, and reduce friction in the fastest moving parts of the train. Consequently, they are beneficial, and eventually as the rest of the industry moved toward 21j watches as "standard" for railroad grade, so did Ball. There again, the 16 size 21j Ball-Hamilton based on the 992 is extremely common. There are also 23J Ball-Hamiltons, which carry a similar premium to a Hamilton 950 vs. a 992. Probably the most valuable Ball watch is the 23j Illinois Ball, but that's mostly because the just didn't make very many of them.