There are historical records of frontiersmen and sailors stopping to dry out black powder that got a dunking in a river or in the bilges. I read some recently that it was common to spread it out to dry.
Here is a related anecdote from me. I was scuba diving on a WWI wreck off NC back in the 1980s. It was an old Cruiser at about 75 foot depth of salt water. In the sand among the rusty steel were a bunch of cylinders about the diameter of a pencil, about 3/4" long. They had a symentrical pattern of holes going longitudinally down the cylinders. I didn't know what they were, but grabbed a few pockets full to take to the surface. They looked like old wood or hard rubber, I took them home. At some point about 6 months later someone said they might be grains powder from large bore Naval guns on the ship. I took a few out on the sidewalk, and threw a match on one. Sure enough, it lit in an instant and burned entirely in a few seconds, with a orange flame. That powder had been UNDER WATER for 80 years!
