powder, when I got it it still had some powder in it. I hate to step on toes but, Im convinced their were a lot moore flasks used in the 19th. century than we use today. There are so many original flasks available by the survival rate is huge. I know by research a lot of English flasks were being imported in the 1830s. Stands to reason there were an ample supply of them at places like Pittsburgh,St Louis etc. I guess they arrent as romantic as the picture of a powder horn on a frontiersman. If they werent used frequently then why is the survival rate as great as their are available, Powder horn survival is considerable a lot less except for the highly ornament, scrimshawed ones that were family heirlooms.Research may find they were fairly common, evan in the frontier regions, Tom