The tumbled fragments looked much less fearsome than they had done in the fog.  He found no difficulty in clambering among them now, when he could see clearly what he was about, and he wormed his way in and out, and up and down, but could not light on any of those tricky spaces which had seemed to him so dangerous before.

And then, as he crawled under one huge slab, a black void lay before him, of no great width but evidently deep.  It took many minutes’ peering into the depths to accustom his eyes to the dimness.

Then it seemed to him that the rough out jutting fragments below would afford a holding, and he swung his feet cautiously down and felt round for foothold.

Carefully testing everything he touched, he let himself down, inch by inch, assured that if he could go down he could certainly get up again.

At first the gale still whistled through the crevices among the boulders, but presently he found himself in a silence that was so mighty a change from the ceaseless roar to which he was becoming accustomed, that he felt as though stricken with deafness.  Up above him the light filtered down, tempered by the slab under which he had come, and enabled him still to find precarious hand and foot hold.

But presently his downward progress was barred by a rough flooring of splintered fragments, and he stood panting and looked about him.

His well was about twenty feet deep, he reckoned, and there were gaping slits here and there which might lead in towards the rock or out towards the sea.  He had turned and twisted so much in his descent that it took him some time to decide in which direction the sea might lie and in which the rock.  And, having settled that, he wriggled through a crevice and wormed slowly on.

He was almost in the dark now, and could only feel his way.  But he was used to groping in narrow places, and a spirit of investigation urged him on.

Half an hour’s strenuous and cautious worming, and a thin trickle of light glimmered ahead.  He turned and worked his way back at once.

There was no slit opposite the one he had tried, but presently, half-way up the well, he made out an opening like the mouth of a small adit.  His back had been to it as he came down, and so he had missed it.

He climbed up and in, and felt convinced in his own mind that this was no simple work of nature.  Nature had no doubt begun, but man had certainly finished it.  For the floor level was comparatively free from harshness, and the outjutting projections of the sides and roof had been tempered, and progress was not difficult.

It was very narrow, however, and very low, and quite dark.  He could only drag himself along on his stomach like a worm.  But he pushed on with all the ardour of a discoverer.

Was it silver?  Was it smugglers?  Or what?  Wholly accidental formation he was sure it was not, though he thought it likely that man’s handiwork had only turned Nature’s to account.