cted as yet what strange happenings would
confront them before many minutes passed by.

CHAPTER XIX

A NEST OF SPIES

Neither of the air service boys had any doubts now with regard to the
character of the grounds they were invading at dead of night. It must be
a private estate. Once it may have been kept up through a lavish
expenditure of money, but of late years things had evidently been
allowed to grow more or less wild.

Tom was following what appeared to be the drive. It was not difficult to
do so, because of the moonlight that sifted down through the bare
branches of the neighboring ornamental trees, now destitute of foliage.

The house was presently discovered. Just as Tom anticipated, it was a
rather large building, that might even be called a mansion, or chateau.
It lay half buried amidst a prodigious growth of trees and bushes.

Jack fancied there was a sort of haunted air about the place, something
uncanny, as he told himself. And then those sobs or screams could not be
forgotten.

"Let's go around first, and see what lies in the rear," whispered Tom.

He had an object in view when he said this. Having noted carefully their
route in coming from the open field where they had left their big plane,
Tom knew that the window from whence the sobbing had come must be either
at the back of the house, or on the eastern side.

He was heading in that quarter now, and looking for signs of a light in
some upper window. This he discovered speedily, and pointed it out to
his companion.

"Whoever was crying, Jack, must be up there," he said, close to the
other's ear so as to insure safety.

"But how can we find out?" queried Jack. "If you say the word I'm
willing to climb up, and learn what's wrong."

"Not yet. We must take a turn around, and pick up more knowledge of this
place, as well as the people who live in the house."

"Then why not creep up and look in at that lower window?" suggested
Jack, pointing as he spoke. "I've seen a shadow passing back and forth,
as if some person were walking up and down like a caged tiger. It's a
man, too, Tom, because I could easily make out his figure, a tall man to
boot."

Tom led the way, with Jack at his heels. They managed to crawl through
the bushes that cluttered the ground close to the wall of the stone
building, and were at length in a position to raise themselves from
their knees and peep under the drawn shade.

Jack was the first to look. Almost instan