happened to him since the two had parted on the preceding evening. When
he showed the forester the marks in the clay, the forester was elated.

"He's a pretty clever rascal who doesn't trip himself up somewhere," he
said. "It's an easy guess who your three fire bugs are. I have a very
great suspicion that the thumb-prints in that ball of clay I took from
your secret camp will match up with some of these marks, and that both
sets of prints will correspond with the marks on the thumbs of one Bill
Collins, though I didn't know that he was in the neighborhood at present.
And it's just as safe a bet that another set of those marks will match the
ends of Lumley's thumbs. If only he had been as considerate as his friend
Collins, and left his calling cards behind him, we'd have a complete case
against him."

"We have," cried Charley, leaping to his feet in sudden excitement.
"Lumley left his thumb-prints in the putty he stuck in his window-sash. I
never thought of them until this moment."

"Excellent!" cried the forester. "I suspect we can find the duplicates for
this third set of prints only when we lay hands on Henry Collins. But I
have a strong suspicion we'll have a chance to make that comparison very
soon."

"How?" asked Charley eagerly. "What do you mean? Have the police made any
arrests?"

"I don't know," replied the forester. "But this is the situation. Lumley
will never dare hang around in the forest, for he will know that every
man in the Forest Service is looking for him. Then, too, he can't have
much food with him."