-set with us, and we can probably advise
headquarters of our predicament with that, and also inform them of the
progress of the enemy movement."

Wearily they turned about, each man loaded down with the necessities
that they had to take with them from the wrecked tractor. It was nearing
night when they reached the apex of the mountain again, and their first
desire was to see whether the Germans had entirely passed around the
mountain.

So far as they could see they had!

But the Boches had done more than that. Their heavy guns were being sent
around either side of the base of the mountain, each quota being part of
a good-sized army. But they were sending another strong detachment up
and over the mountain itself!

And the first section of it was less than a mile below, spreading out in
such a way that while a part of it would come over the top, other parts
would go around either side, and they would be fan-like in shape,
forming a virtual comb in the search for any enemies who might be
lurking there.

"The pack-set!" ordered the lieutenant. In a very short time it was set
up, and Jerry was grinding the crank to generate power while the officer
flashed out the headquarters call.

In a moment a message began to come: "J-X. J-X. J-X. J-X."

Lieutenant Mackinson nervously began tapping the key again, but the only
reply was the insistent call for J-X, which was the code call for
themselves.

"No use," said the young officer at last. "We can catch them, with their
stronger range, but we haven't radius enough to send to them."

"Those troops cannot reach here until after dark," said Slim.

"No," Lieutenant Mackinson acknowledged, "but they are in such numbers
that we could not hope to keep our identity or presence hidden, and
they are getting around the mountain quicker than we could get down and
beyond their line."

"It looks as though we were hemmed in," said Frank Hoskins in an even
tone.

"Yes," agreed Jerry, "and in a tight place."

CHAPTER XVII

THE LIEUTENANT'S INVENTION

While the others speculated upon various means of escape, and in turn
found every one of their suggestions useless, Lieutenant Mackinson had
remained silent and in deep thought. Finally, his countenance showing
that he had arrived at a conclusion, he turned to the others.

"Come with me," he said simply, "it is the only way."

"Where are you going?" Joe asked quickly.

"Back to the tractor," the lieutenant replied. "Hurry