And then, abruptly, they came upon a stretch of rock and sand from which the heat vibrated as if from an oven. To the north, the Cheshire plain spread before them like a green and yellow patchwork quilt dotted with toy farms and houses. Here the Edge dropped steeply for several hundred feet, while away to their right the country rose in folds and wrinkles until it joined the bulk of the Pennines, which loomed eight miles away through the haze.

The children stood for some minutes, held by the splendour of the view. Then Susan, noticing something closer to hand, said, “Look here! This must be one of the mines.”

Almost at their feet a narrow trench sloped into the rock.

“Come on.” said Colin, there’s no harm in going down a little way—just as far as the daylight reaches.”

Gingerly they walked down the trench, and were rather disappointed to find that it ended in a small cave, shaped roughly like a discus, and full of cold, damp air. There were no tunnels or shafts: the only thing of note was a round hole in the roof, about a yard across, which was blocked by an oblong stone.

“Huh!” said Colin. “There’s nothing dangerous about this, anyway.”

All through the afternoon Colin and Susan roamed up and down the wooded hillside and along the valleys of the Edge, sometimes going where only the tall beech stood, and in such places all was still. On the ground lay dead leaves, nothing more: no grass or bracken grew; winter seemed to linger there among the grey, green beeches. When the children came out of such a wood it was like coming into a garden from a musty cellar.

In their wanderings they saw many caves and openings in the hill, but they never explored farther than the limits of daylight.

Just as they were about to turn for home after a climb from the foot of the Edge, the children came upon a stone trough into which water was dripping from an overhanging cliff, and high in the rock was carved the face of a bearded man, and underneath was engraved: