I’m writing a novel currently, and am trying to puzzle out how exactly bilge pumps worked during the Pre-Industrial Era. I know that it was commonplace to use a hollowed out tree running vertically from the bilge to the main deck as a pump, with stoppers intermittent between the top and the bottom, and I know that it worked on a pulley system that was manned by the crew at a windlass, but I’m confused as to where the water was siphoned from as well; is it siphoned from within the bilge? Is it siphoned from outside of the ship? How did they remove the water that got in the bilge, then? With water buckets? Please help educate me on the matter.