This movement is from a clock that was brought in for repair today. It is similar to the Seth Thomas 15 day 86 movement. It has a 30 tooth escape wheel and a drive gear off the rear of the movement going to drive gears on either side. The number 80 or it might be 30 is stamped on the leg. Neither of those numbers matches up with movement listing in Trans Seth Thomas book. Any information would be helpful.
The case measurements are: 53X22X13 with a 42 inch pendulum.

Back view

Interesting clock Ken, Wonder what the two side gears drive. Time clock?
I have a fondness for the 86 movements. Probably because I have two and the first one I got is very reliable and keeps accurate time with no trouble.

Tried to post a link to another thread but it's evidently too large to load?

Search for Seth Thomas Mission There's a chart there showing the variations on the 86 movement.

pretty amazing if you ask me. Seth Thomas was a great innovator and made movements for many splendid varieties of clock !!! I've never seen that configuration,ever!!!!

Just for comparison here's my 86F 15 day

And my 87 chain wind

I've restored many Seth Thomas clocks and have never seen a Seth Thomas movement with out The ST in a diamond logo.I don't see it on this movement.Norm

Norm, the movement is correctly signed on the arched middle piece behind the intermediate hour wheel.