How is the trophy stored on the ship

The Pequod's whale's head was hoisted against the ship's side about half way out of the sea and strained the craft. Ahab watches the head and says "speak thou vast and venerable head which, though ungarnished with a beard, yet here and there lookest hoary with mosses . . . thou hast seen enough to split the planets and make an infidel of Abraham, and not one syllable is thine."