And at last he came to the great sea-serpent himself, lying dead at the bottom; and as he was too thick to scramble over, Tom had to walk round him three-quarters of a mile and more, which put him out of his path sadly; and, when he had got round, he came to the place called Stop. And there he stopped, and just in time. For he was on the edge of a vast hole in the bottom of the sea, up which was rushing and roaring clear steam enough to work all the engines in the world at once; so clear, indeed, that it was quite light at moments; and Tom could see almost up to the top of the water above, and down below into the pit for nobody knows how far. But, as soon as he bent his head over the edge, he got such a rap on the nose from pebbles, that he jumped back again; for the steam, as it rushed up, rasped away the sides of the hole, and hurled it up into the sea in a shower of mud and gravel and ashes; and then it spread all around, and sank again, and covered in the dead fish so fast, that before Tom had stood there five minutes he was buried in silt up to his ankles, and began to be afraid that he should have been buried alive. And perhaps he would have been, but that while he was thinking, the whole piece of ground on which he stood was torn off and blown upwards, and away flew Tom a mile up through the sea, wondering what was coming next. At last he stopped--thump! and found himself tight in the legs of the most wonderful bogy which he had ever seen. It had I don't know how many wings, as big as the sails of a windmill, and spread out in a ring like them; and with them it hovered over the steam which rushed up, as a ball hovers over the top of a fountain. And for every wing above it had a leg below, with a claw like a comb at the tip, and a nostril at the root; and in the middle it had no stomach and one eye; and as for its mouth, that was all on one side, as the madreporiform tubercle in a star-fish is. Well, it was a very strange beast; but no stranger than some dozens which you may see. "What do you want here," it cried quite peevishly, "getting in my way?" and it tried to drop Tom: but he held on tight to its claws, thinking himself safer where he was. So Tom told him who he was, and what his errand was. And the thing winked its one eye, and sneered: "I am too old to be taken in in that way. You are come after gold--I know you are." "Gold! What is gold?" And really Tom did not know; but: the suspicious old bogy would not believe him.