Aircraft Dope: Celluloid in Acetone, Alcohol and Benzole with Beeswax and Paraffin Wax (Groves, US 1,366,256)

Dope is the varnish brushed onto the covering of an aircraft frame: it tightens the skin and seals it. Plain celluloid dope dries too fast to brush evenly and lets water through. Groves added beeswax and paraffin wax together, which slows the drying and keeps the coat waterproof. Result: a brushable celluloid dope for covering wings and frames. Source: Groves, US 1,366,256 (1921). Not given: how the solvent is split between acetone, alcohol and benzole. Picture drawn by Youblob.