"Help!" called Prescott, suddenly, for he found the rope slipping through his fingers, the friction burning his flesh. Mr. Bull had succeeded in backing four feet away from the tree. He would speedily be able to free himself altogether.
Tom and Dave now came running. They threw their weight and muscle upon the rope to hinder the captive animal. But that great creature seemed likely soon to overcome the strength of all those combined against him.
"Come on!" called Dick, backing away on a new course. "Off this way, to the next tree behind me. Hold on and pull for every pound you're worth."
Seeing his opponents plainly engaged in making some new move the wild animal halted, eyeing them balefully. That hesitation proved fatal to his immediate freedom, for Dick had succeeded in getting the rope around the tree behind him. Now he took another quick hitch, supplementing this with a knot, then another and a third.
"I guess we may all let go of the rope now," Prescott smiled. "I don't believe the bull can pull successfully against that triple knot."
Mr. Bull was trying it, at any rate. His angry bellows were almost as loud as the roaring of a lion. Dirt flew. The beast exerted its whole power in its efforts to get free.
"The knot will hold," pronounced Dr. Bentley, after a critical survey. "The great danger is friction, which may wear out that part of the rope hitched around the first tree. If that happens we shall all have to run for our lives. Come back here, Prescott! What are you going to do?"
For Dick, leaving the little group, had started on a run for the bull.