Collection, Preservation and Display of Old Lawn Mowers
Some text or a picture might help
My only Pennsylvania catalogue is mid 1920's & no mention of rubber tyres, but I know over your side of the pond they did often add them as mentioned on other recent threads on the forum.
Any indication on the handle or outside of wheels to more wording?
We do have a club member & expert on USA mower history who looks to be a neighbour of yours, well 100 miles North so not far in the scale of things, suggest you send him an email Jim Ricci firstname.lastname@example.org but please post his answer on forum for us all to see.