"Can't you guess?" asked Lilly.

"I have an idea now. It has just occurred to me."

Lilly rose to his full height, tugging at his moustache with both hands, gazing fixedly at Tad Butler.

"It's more work of that miserable whelp. He's done it this time. I see how it was. I should have thought of that before. If my eyes had been as sharp as yours, Master Tad, you wouldn't need to have told me."

"Tell us what you suspect," urged Professor Zepplin, who was as much puzzled as the rest. Even Stacy was regarding the guide with inquiring eyes. The latter was striding up and down, tugging at his moustache as if he owed it a grudge.

"What I suspect? I don't suspect at all. I know now, thanks to Master Tad's keen scent. What has been done is this. Some whelp, knowing what we were going to do, has hit the bear trail leading a dog. He knew the wolves were in that vicinity, so he rode along the back trail, leading the dog behind him, knowing full well that the wolves would scent it, and, knowing it was a lone dog, would follow it. You see he figured that the pack would sooner or later come up with our hounds. He knew that there would be a battle and he hoped we would lose all our dogs."

"The cold-blooded scoundrel!" exclaimed Ned Rector.

"There! What did I tell you, Tad?" cried Stacy. "I ought to have shot the beast while I had the chance. He played us about as I thought he would. Why, if you had let me have my way, I should have taken his horse away from him and set him adrift. I guess he wouldn't have played any such miserable trick on us. No, sir, he would have all he wanted to do to get out of the woods, let alone dragging a lone dog along the bear trail to call the wolves to our pack. Oh, what a beast!"

"It is well that your revengeful disposition was not allowed free range," answered the Professor rebukingly.

"It is done now. We can't help ourselves," said Tad.