The floorboards around the outside wall of the upstairs have spaces between them. That was so that grain could be thrown down on those boards and then mules walked around and around on it so that the grain would fall between the boards into the bottom of the barn and the straw would stay on the floor. (I assume that when this was done, there wasn’t a bench setting in the way of the mules, as this one seems to be positioned.)
What an interesting man President Washington must have been. Anyone with such a creative mind must have been a wonderful conversationalist.