An angry jerk of the reins emphasised his mistake.

He resented it, as he had resented much in his treatment that morning already.
His head came round furiously, his heels slipped in the crumbling gravel, he kicked out wildly for safer holding, and in a moment he was over.
At the first feel of insecurity behind, Torode slipped deftly out of the saddle.

He still held the reins and endeavoured to drag the poor beast up.
But Black Boy's heels were kicking frantically, now on thin air, now for a second against an impossible slope of rock which offered no foothold.

For a moment he hung by his forelegs curved in rigid agony, his nostrils wide and red, his eyes full of frantic appeal, his ears flat to his head, his poor face pitiful in its desperation.

Torode shouted to him, dragged at the reins--released them just in time.
Those who saw it never forgot that last look on Black Boy's face, never lost the rending horror of his scream as his forelegs gave and he sank out of sight, never forgot the hideous sound of his fall as he rolled down the cliff to the rocks below.
The girls hid their faces and sank sobbing into the heather.