Or intestines of cattle. https://en.wikipedia.org/wiki/Zeppelin https://en.wikipedia.org/wiki/Zeppelin Early Zeppelins used rubberised cotton for the gasbags,

Or intestines of cattle. https://en.wikipedia.org/wiki/Zeppelin https://en.wikipedia.org/wiki/Zeppelin Early Zeppelins used rubberised cotton for the gasbags, but most later craft used goldbeater's skin, made from the intestines of cattle