I always thought that in the age of fighting sail and wooden ships, gun crews aimed their cannons at the waterline because that would sink the enemy’s ship. But, I kind of wondered, if that were the case, why not aim slightly lower, where a good shot likely would let even more water in the enemy’s hull, and be more difficult to plug? (I thought the answer was perhaps that at many angles, the cannonball might skip, rather than plunge into the water, but I wasn’t sure.)