… yes they used cow gut/intestines 🐄🐄. 7 layers of cow gut where sewn onto a carrier layer of fabric to create an airtight balloon that could hold hydrogen lifting gas for some days 🎈. 50.000 cows where slaughtered for one gas-cell
Advantages over rubber of cow gut:
- rubber-cotton balloons got brittle with repeated uses with hydrogen filling. Cow gut is a flexible material that lasted longer, though expensive.
- rubber balloons can get statically charged. A small spark can flame all the hydrogen at once. Cattle gut does not charge as quickly as rubber.
Source:
- https://en.wikipedia.org/wiki/Goldbeater's_skin#Applications
- https://de.wikipedia.org/wiki/Goldschlägerhaut german article mentions some more numbers data.
- https://en.wikipedia.org/wiki/Airship#Envelope
thank you for adding more sources! I am also interested in this. They stacked 7 layers on top of each other. Alternating layer patterns (similar to a brick wall stacked alternating overlap) to prevent gas escape seems logical to me.