Trevorrick River was but a little stream to have fretted so deep a cleft between the hills as that which sloped from the main road of Tregols parish to the sea. From the source to the engulfing sands was barely a mile, and the twinkling waters, if full and fierce in winter, showed a summer fear of their own broad stepping-stones. Nevertheless the sharp declivities, the juttings of rock, even the shelves and crags and walls of Dark Head, had been formed by the gnawing of this tiny but persistent flow.