My very old clock

I have a Reglator wall clock made by The E, Ingraham Co. and would like to know more about it. It is also a 31 day clock. Any help would be great. I found this clock at an old house that is going to be bulldozed to the ground and the builder of the soon to be new house said I was more than welcome to it, so here we are.

I would like to find out more about it and if possible what its worth, I have had a couple of offers on it but i'm not really sure what its worth.