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Bethink yourself also of another thing. When two large, loaded Indiamen chance to crowd and crush towards each other in the docks, what do the sailors do? They do not suspend between them, at the point of coming contact, any merely hard substance, like iron or wood. No, they hold there a large, round wad of tow and cork, enveloped in the thickest and toughest of ox-hide. That bravely and uninjured takes the jam which would have snapped all their oaken handspikes and iron crow-bars. By itself this sufficiently illustrates the obvious fact I drive at. But supplementary to this, it has hypothetically occurred to me, that as ordinary fish possess what is called a swimming bladder in them, capable, at will, of distension or contraction; and as the Sperm Whale, as far as I know, has no such provision in him; considering, too, the otherwise inexplicable manner in which he now depresses his head altogether beneath the surface, and anon swims with it high elevated out of the water; considering the unobstructed elasticity of its envelop; considering the unique interior of his head; it has hypothetically occurred to me, I say, that those mystical lung-celled honeycombs there may possibly have some hitherto unknown and unsuspected connexion with the outer air, so as to be susceptible to atmospheric distension and contraction. If this be so, fancy the irresistibleness of that might, to which the most impalpable and destructive of all elements contributes.