An antique powder horn.
Powder Horns were used before the invention of the modern cartridge. They were usually made from cow or buffalo horns and were primarily used with eighteenth and nineteenth century muskets (eg the Springfield Model 1795 Musket), until the time that these muskets were rendered obsolete by the invention of breech loading firearms and the later development of self-contained cartridges.
The use of the organic animal horn and nonferrous metal parts made sure that the powder wouldn't detonate during storage and loading. Horns in particular were found to be waterproof and already hollow on the inside. Some horns are now preserved as examples of folk art.
