ted that the Americans were ready to make a
more stupendous push than had as yet been undertaken, with the idea of
capturing a whole division, or possibly two, before they could get away;
and this bombardment was continued in hopes of discouraging them.

The two Air Service Boys did not bother themselves about this, being
content to leave all such matters to those in command. They had their
orders and expected to obey them to the letter, which was quite
enough for them.

Once more in their dugout, Tom and his comrade crawled into their limited
sleeping quarters simply to rest, neither of them meaning to try to
forget themselves in slumber.

When the time came for action they were soon crawling out of the hole in
the ground. As pilots came and went unnoticed, each intent on his
individual work, their departure caused not the faintest ripple. In fact,
there were two other airmen who also came out and joined them when making
for the place of the temporary canvas hangars, they, too, having had
secret orders concerning this same night raid.

Arriving on the open field, they found a busy scene awaiting them. Here
were mechanics by the score getting planes ready for ascension. The
hum of motors and the buzz of propellers being tuned up could be heard in
many quarters.

Those sounds always thrilled the hearts of the two boys; it seemed to
challenge them to renewed efforts to accomplish great things in their
chosen profession. When, however, they reached their own hangar and
found a knot of mechanics working furiously, Tom's suspicions
instantly arose.

"What's wrong here?" he asked the man who was in charge of the gang.

"There's been some sort of ugly business going on, I'm afraid," came the
reply; "for we're replacing several wire stays that look as if they'd
been partly eaten by a corrosive acid. Smacks of rank treachery,
Sergeant."

CHAPTER V

THE AIR RAIDERS

Upon hearing the words uttered by the mechanic who handled the men
working at their battleplane, Tom and his chum exchanged meaning looks.

"Can you make it perfectly safe again before half an hour passes?" asked
the former anxiously.

"Surely," came the confident reply. "I know what's in the wind, and
you'll be fit for any sort of flight when another fifteen minutes has
gone by. We're on the last stay now, and I've carefully examined the
motor and every other thing about the plane. Don't fear to risk your
lives on my report. I'd go up myself w