But, where the glen of its course approaches the vale of the river,
Met and blocked by a huge interposing mass of granite,
Scarce by a channel deep-cut, raging up, and raging onward,
Forces its flood through a passage so narrow a lady would step it.
There, across the great rocky wharves, a wooden bridge goes,
Carrying a path to the forest; below, three hundred yards, say,
Lower in level some twenty-five feet, through flats of shingle,
Stepping-stones and a cart-track cross in the open valley.
But in the interval here the boiling pent-up water
Frees itself by a final descent, attaining a basin,