They came to an old wall overgrown with fern and brambles; just below it was the mossy ruin of a cot, the fire-place still showing, the remains of the wall a yard in width. They were among works concerning which history is hazy. They were in a place where the old miners wrought the tin, and among the ruins of their industry. Perhaps a rich mine was there once. Possibly it was the secret of that place which was guarded so well by the Carthaginian captain, who sacrificed his tin-laden galley to avoid capture by Roman coastguards. The history of the search for "white metal" upon Dartmoor has yet to be learnt. They went cautiously round the ruin, and upon the other side Eli dived across the bleached skeleton of a pony and became mixed up in dry bones. A deep cleft appeared overhung with gorse and willows. Eli would have dived again had not Pendoggat been holding him. They clambered across, then made their way along a shelf of rock between the cliff and the river. Beyond, Pendoggat parted the bushes, and directed the light of his lantern towards what appeared to be a narrow gully, black and unpleasant, and musical with dripping water. "Go on," he said curtly. The minister held back. He was not a brave man, and that black hole in the side of the moor conjured up horrors. "Take my hand, and let yourself down. There's water, but not more than a foot," said Pendoggat. He pushed Eli forward, then caught his collar, and lowered him like a sack. The minister shuddered when he felt the icy water round his legs and the clammy ferns closing about his head. Pendoggat followed. They were in a narrow channel leading towards a low cave. Frogs splashed in front of them. Small streams trickled down a hundred tiny clefts. "This is a very disagreeable situation, Mr. Pendoggat," said Eli meekly. "Come on," said the other gruffly. "I'll show you something to open your eyes. Step low." They splashed on, bent under the arch of the cave, and entered the womb of the moor. Hundreds of feet of solid granite roofed them in. They were out of the wind and moonlight. Pendoggat guided the minister in front of him, keeping him close to the wall of rock to avoid the deep water in the centre. About twenty paces from the entry was a shaft cut at right angles. They went along it until they had to stoop again. "Be'old, Mr. Pendoggat!" cried Eli, with amazed admiration. "Be'old the colours! I have never seen anything so beautiful in my life. What is it? Jewels, Mr. Pendoggat? You don't say they are jewels?" "Pretty, ain't they? More than pretty too. Now you know what I've brought you for," said Pendoggat, as he turned up the light to increase the splendour of the wall.