"But," sharply replied Shandon, "there must be facts to establish that theory, and if there are any," added he with irony, "our universally well-informed doctor ought to know them." "Well," replied the above-mentioned, with amiable satisfaction, "if it interests you, I can tell you that whales, wounded in Davis's Straits, are caught some time afterwards in the neighbourhood of Tartary with the European harpoon still in their flanks." "And unless they have been able to double Cape Horn or the Cape of Good Hope," replied Shandon, "they must necessarily have rounded the septentrional coasts of America--that's what I call indisputable, doctor." "However, if you were not convinced, my dear fellow," said the doctor, smiling, "I could still produce other facts, such as drift-wood, of which Davis's Straits are full, larch, aspen, and other tropical trees. Now we know that the Gulf Stream hinders those woods from entering the Straits. If, then, they come out of it they can only get in from Behring's Straits." "I am convinced, doctor, and I avow that it would be difficult to remain incredulous with you." "Upon my honour," said Johnson, "there's something that comes just in time to help our discussion. I perceive in the distance a lump of wood of certain dimensions; if the commander permits it we'll haul it in, and ask it the name of its country." "That's it," said the doctor, "the example after the rule." Shandon gave the necessary orders; the brig was directed towards the piece of wood signalled, and soon afterwards, not without trouble, the crew hoisted it on deck. It was the trunk of a mahogany tree, gnawed right into the centre by worms, but for which circumstance it would not have floated. "This is glorious," said the doctor enthusiastically, "for as the currents of the Atlantic could not carry it to Davis's Straits, and as it has not been driven into the Polar basin by the streams of septentrional America, seeing that this tree grew under the Equator, it is evident that it comes in a straight line from Behring; and look here, you see those sea-worms which have eaten it, they belong to a hot-country species." "It is evident," replied Wall, "that the people who do not believe in the famous passage are wrong."