e rear, including food and
ammunition trains, field hospitals, etc., to fall back, in order to make
way for the strategic retreat of those on the front when the moment for
that retreat came.

Everything moved like clockwork, and with the greatest possible speed.
And throughout it all men on both sides were shooting, shouting,
shrieking, fighting, falling, while others, trapped in their dug-outs,
either surrendered or fought desperately on until they fell wounded or
lifeless before superior numbers.

Half a mile in the air, apparently over a point midway between what had
been the first-line trenches of the opposing armies, a stationary
balloon showed where Jerry and an observation officer were doing duty on
that fateful day. Jerry was operating a telephone that ran directly to
division headquarters, and hardly a moment passed when he was not
repeating some observation of the other man in the basket with him, or
relaying to him a query from the commander below.

Every detail of that tremendous battle Jerry knew. His own occasional
glimpses over the side informed him of the temporary reverses his own
army was suffering, while the remarks of the officer told him where the
Germans were meeting their bitterest repulses, where they were drawing
up their heaviest forces of reserves, what quick changes were being made
in their general line of formation, and how far back their forces seemed
to extend.

Slim Goodwin, busy as he was with the wireless at headquarters, found
time for occasional glances upward at that balloon, to make sure that
thus far his friend was still safe.

And even in the thick of machine-gun fire and shrapnel, where Lieutenant
Mackinson, Joe, Frank Hoskins and two or three others were laying a new
line of communication, the wavering, swaying target was watched from
time to time, and speculations made as to how long it could remain
without being punctured by a bullet, thus forcing its two occupants to
resort to their parachutes to make a landing.

It was now well into the afternoon. The Germans had swept into the
places vacated by the Americans and French, and still the battle raged.
It was now that Slim began to wait anxiously for the new development,
which his familiarity with the secret orders issued made him know was
coming.

And finally it did come, and in a way that staggered the Boches.

The Americans and French had retreated to a general line which permitted
a quick re-mobilization to the bes