t advantage. There their front-line
ranks held firm, while the new formation was being effected behind them.
It was about four o'clock in the afternoon when this was complete.

Then, in concerted action, the lines opened at alternate points, and
pairs, dozens, scores of the huge armored tanks rolled through, their
big guns already blazing shells into the ranks of the disconcerted
enemy.

Nothing could halt them. They climbed trench parapets, descended into
gullies, came out upon level land, and over their whole path swept
destruction to the Germans.

Unable either to resist or to stop the progress of the tanks, which were
followed by whole divisions of infantry, the Boches were forced to
retreat and not only abandon every foot of the ground they had gained,
but to sacrifice a part of their own first line as well.

[Illustration: Scores of Huge Armored Tanks Rolled Through.]

It was one of the greatest and at the same time one of the most sudden
reprisals of the war up to that time, and the victory that had been
snatched from defeat was cheered by thousands of Americans and Frenchmen
as they again took possession of their own trenches, or pushed onward
across No Man's Land to occupy those which the Germans were now
abandoning.

The sun was setting, and soon, in great measure, at least, hostilities
would be suspended for the night.

Their work completed, Lieutenant Mackinson and his men were on their way
back to make their report when they met Slim, who had been relieved for
the night at headquarters.

"What time did Jerry come down?" Joe asked, after they had passed
remarks about the various thrills of the day.

"Don't know," Slim answered, "but I saw them there at four o'clock, and
they weren't there when I looked again, about half an hour later, so you
can judge pretty well for yourself."

"Guess he had a pretty good bird's-eye view of the whole thing," said
Joe, as they passed on, to meet again before mess.

Except for spasmodic outbursts here and there, the trench duel had
almost entirely subsided, and the heavy roar of the artillery also was
punctuated with longer pauses. Whatever the morrow might bring, the
night promised to be fairly quiet, while each side took account of stock
and made necessary repairs, or altered their plans to meet the new
situation.

Our young friends were busy with wash basin, soap and water, taking off
the grime in preparation for the evening meal and wondering where Jerry
w