So I’m guessing this is a precursor to the modern RO skeletons (15305,15407, and other more complicated versions) that everyone goes crazy for. Yours is the original.😍
I wonder how far back skeleton dials can be traced back. Given what I’ve seen, I would not be surprised to learn of some degree of skeletonization going back to the 1800s. Fascinating topic for me given how much I love skeleton dials.