Revolutionary War era Sander/Pounce Pot Shaker

Revolutionary War era Wooden Sander/Pounce Pot Shaker.  One of these would have been on every desk in the colonies The sander, otherwise known as a pounce pot, functions in a very similar manner to a salt shaker, and would have been filled with a finely ground powder (pumice, gum-sandarac rosin, or the crushed bones of cuttlefish) or sand to pour over freshly written documents