How Did Sailors Wipe Their Butt?

As can be seen in the video below, close to the ship's head — the toilets in the bow or “head” of the ship — there was a long rope ending in a short rag that hung over the side into the water. After using the head, the sailor could then clean his backside with the wet rag then drop the rope back over the side.

Did sailors poop off the poop deck?

Sailors didn't poop off the poop deck. The deck's purpose was for navigational and observation purposes and there were other locations for the sailors to use as toilets.

How did sailors poop on ships?

Ships of the line frequently included systems of pipes, septic tanks and even primitive forms of flush toilets.