light squarely on the work."

Tom worked for some time. He tapped as gently as possible when knocking
out the dent made by the bullet, and he gradually removed the cause of
the trouble. He was just finishing with the spark-plug when the
confidence of the air service boys received a sudden jolt.

CHAPTER XVIII

THE LONE HOUSE BY THE ROADSIDE

"Listen, Tom!" hissed Jack.

The other had just sighed with relief on completing the work of
replacing the spark-plug that had become fouled with oil.

"I, too, heard it plainly, Jack!" he breathed.

"Was it someone screaming or sobbing?" asked the other breathlessly.

"Sounded like it to me."

"And either a woman or a girl, at that!" hazarded his chum in
bewilderment.

"It might have been a boy," suggested Tom. "There it is again."

Both of them listened. Peculiar sensations crept over them as they stood
and thus strained their ears to catch any further sounds. Sobbing at any
time is enough to arouse the feelings of a sensitive nature; but heard
in the dead of night, and under the conditions that surrounded the two
young aviators, made it all the more thrilling.

Jack in particular was touched to the heart.

"Say, that's a queer thing, Tom!" he muttered. "Why should anybody be
crying or screaming like that away off here, and at this time of night?"

"Oh, there are many who are weeping in these dark days," said Tom
gravely. "The men in myriads of families will never come home again.
Perhaps a mother, or it may be a sister, has just had word that son,
father, or brother has been shot down in battle."

Jack shuddered. Why should his thoughts instantly fly to the Boche pilot
whom they had met and fought and conquered while on the way to Metz on
their present perilous mission? It had been a fair fight, and a case of
their lives or his. Nevertheless Jack shuddered as he remembered how the
other had gone down after that last exchange of gunfire.

"Tom, notice that it comes from almost the identical direction where I
told you I heard the crowing of a rooster a while ago," he hastened to
say, more to rid his mind of those ghastly thoughts than anything else.

What a strange fatality if this should be the home of the unfortunate
Teuton pilot of that Fokker machine, and the one who mourned was his
mother or a young sister, or perhaps his wife!

"That means there's a house not far away, possibly an estate of some
kind," mused Tom, as though turning over some sudde