Absolutely fascinating Matt. It tells us something that we didn't know before - old airgun bellows parchment was the same material as document parchment, and not some special version of pig skin or goat skin as might have been the case.

It would be great to see a blow-by-blow account of how you restored your bellows, as I don't think this has been documented before. Can't wait for the video!

Cheers, John