him, as well as to see that his machine is in perfect trim.

Experts are needed to see to it that the machine and the aviator are in
perfect trim, leaving for the airman himself the trying and difficult
task, sometimes, of flying upside down, while he is making observations
of the enemy with one eye, and fighting off a Boche with the
other--ready to kill or be killed.

Sergeants Tom Raymond and Jack Parmly, chums and fellow airmen flying
for France, started toward the aerodromes where their machines were kept
when not in use. They were both attired now for hard and not very clean
work, though the more laborious part would be done by mechanics at their
orders. Still the lads themselves would leave nothing to chance. Indeed
no airman does, for in very, truth his He and the success of an army
may, at times, depend on the strength or weakness of a seemingly
insignificant bit of wire or the continuity of a small gasoline pipe.

"Well, it'll seem good to get up in the air again," remarked Jack. "A
little rest is all right, but too much is more than enough."

"Right O, my sliced liberty bond!" laughed Tom. "And now--"

Their talk was interrupted by a cheer that broke out in front of a
recreation house, in reality a YMCA hut, or le Foyer du Soldat as it
was called. It was where the airmen went when not on duty to read the
papers, write letters and buy chocolate.

"What's up now?" asked Jack, as he and his chum looked toward the
cheering squad of aviators and their assistants.

"Give it up. Let's go over and find out."

They broke into a run as the cheering continued, and then they saw hats
being thrown into the air and men capering about with every evidence of
joy.

"We must have won a big battle!" cried Jack.

"Seems so," agreed Tom. "Hi there! what is it?" he asked in French of a
fellow aviator.

"What is it? You ask me what? Ah, joy of my life! It is you who ought to
know first! It is you who should give thanks! Ah!"

"Yes, that's all right, old man," returned Jack in English. "We'll give
thanks right as soon as we know what it is; but we aren't mind readers,
you know, and there are so many things to guess at that there's no use
in wasting the time. Tell us, like a good chap!" he begged in French,
for he saw the puzzled look on the face of the aviator Tom had
addressed.

"It is the best news ever!" was the answer. "The first of your brave
countrymen have arrived to help us drive the Boche from France! The
fir