He stopped amazed, and at that instant heard the report of a rifle somewhat to his right and knew that a bullet had passed beneath him.

Scarcely had he realised this when there was a sudden commotion in his hair, and the soft black felt hat that he was wearing started from his head, apparently of its own accord, and, after twirling round twice or thrice in the air, fell gently to the earth, just as the sound of a second report reached his ears.

It was now evident that somebody was firing at him; so, jumping up from his crouching position, John tossed his arms into the air and sprang and shouted in a way that left no mistake as to his whereabouts.

In another minute he saw a man on horseback, cantering easily towards him, in whom he had little difficulty in recognising Frank Muller.

He picked up his hat; there was a bullet-hole right through it.