t the door,
just as though he felt perfectly at home there.

"Well, what next?" remarked Andy.

For reply the other beckoned, and started hurriedly to gain the shelter
of the woodshed near by.

"What's this for?" questioned Andy, when they were once more crouched
down, in a position where they could not be easily seen.

"Stop and think," answered the other; "if he just happened to look out
of a window on this side of the house he'd see us easily and our
suspicious actions would tell him we were on to his game. Now even if he
looks he won't see anything."

"Huh! and do we stay here all afternoon just doing nothing; while p'raps
he's taking a nap indoors?" grumbled the other, who wanted to be moving,
and was never satisfied when not in action.

"Wait!" was all Frank would say.

Perhaps he could see further ahead than his cousin, and guessed
something of what was likely to occur. They had not taken pains to warn
Sallie or her mother to keep from mentioning the fact of their happening
around; and chances were, that as soon as Casper Blue heard that the
Bird boys had dropped in, he would become immediately suspicious.

On questioning the girl he would be apt to learn how curious Frank and
Andy had seemed about him; and Sallie might even admit that they had
asked to see his wonderful collection of rare and costly butterflies.

Well, if such a thing did occur, of course the keen-witted man would
immediately know that the cat was out of the bag. Realizing that there
must be a great hue and cry throughout the entire county just then, with
reference to the yeggs who had looted the bank, he could easily imagine
what had brought these boys here.

Through association with Todd Pemberton, Casper must have learned a
whole lot with regard to Frank and his cousin. Being an aviator himself
he would naturally take an immediate interest in boys who had given such
a good account of themselves in the field of aeronautics. The attempt to
steal the hydroplane in the first place before they turned to Percy
Carberry's biplane proved that they knew all about the Bird boys. And
so, learning of their presence would immediately give Casper warning
that his hideout was no longer a secret, but that the net of the law
must be closing around him.

What then?

Would he, like a desperate man, attempt to capture these venturesome
lads, so as to keep them from informing the authorities at Bloomsbury?
Either that, or else he would think that,