“Wooden ships—that is possible,” replied the Canadian, “but I have never seen it done; and, until further proof, I deny that whales, cetaceans, or sea-unicorns could ever produce the effect you describe.” “Well, Ned, I repeat it with a conviction resting on the logic of facts. I believe in the existence of a mammal powerfully organised, belonging to the branch of vertebrata, like the whales, the cachalots, or the dolphins, and furnished with a horn of defence of great penetrating power.” “Hum!” said the harpooner, shaking his head with the air of a man who would not be convinced. “Notice one thing, my worthy Canadian,” I resumed. “If such an animal is in existence, if it inhabits the depths of the ocean, if it frequents the strata lying miles below the surface of the water, it must necessarily possess an organisation the strength of which would defy all comparison.” “And why this powerful organisation?” demanded Ned. “Because it requires incalculable strength to keep one’s self in these strata and resist their pressure. Listen to me. Let us admit that the pressure of the atmosphere is represented by the weight of a column of water thirty-two feet high. In reality the column of water would be shorter, as we are speaking of sea water, the density of which is greater than that of fresh water.