So I have heard about the Sinking ship proof, but I have sailed on several Tall ships before and have used a telescope out on the open ocean. I have never experienced the situation that is described. For me, once a ship disappears over the horizon, I can no longer see it. telescope or not. Another thing, if it were true that a telescope could make it so that you can see over the horizon then theoretically, if I had a good enough telescope, I could see across the Atlantic ocean to Spain? I live in Maine. New information has been brought to my attention so I will also now ask, why did ships have a crows nest on top of the mast if not to overcome the curvature of the earth?