"I don't believe it!" he cried.

"Here, you! Stop and guard this prisoner, while I go and take charge of the search myself." As Mr.Riley departed, the new guard entered the hut, leaned his rifle against the wall, and took a seat near the door.
Then Billy Brackett stooped and whispered to his ever-faithful comrade, "Watch him, Bim!" and the dog answered with a low growl that spoke volumes.

Turning to the guard the young engineer said, "My friend, if you make the slightest motion or shout for help, that bull-dog will fly at your throat.

I am going to leave you alone with him for a minute, and as you value your life, I beg of you to keep perfectly quiet until you hear from me." With this the prisoner leaped lightly from the window and disappeared.
[Illustration: "'Watch him, Bim!'"] For two minutes the guard sat as motionless as though carved from stone, his fascinated gaze fixed on the gleaming teeth and bloodshot eyes of the bull-dog that stood rigidly before him.

Then a shrill whistle rang out on the still air, and at its sound the dog, dashing past him, disappeared like a flash.