o bring
up, and fire wood to scurry for when the chance offered, for it was
not often possible to bring up hot rations to the front lines, and the
boys heated their own as best they could, in discarded tin cans with a
few twigs for fuel.

There were lines of trenches to cut, dugouts to repair after they had
been blown to bits by the German guns, and there was barbed wire to
replace under cover of darkness when it had been severed by the rain
of steel and lead from the enemy's guns.

So the three chums and their comrades found no lack of things to keep
them busy in the trenches. They had their hours off, of course, when
they were permitted to go back to the dugout, and there, in
comparative safety, they might try to sleep. This was not easy, for
though in a manner they became used to the constant roaring and
blasting of the big guns, there was always an under-current of
disturbances of other kinds. They were on the firing line, and the
enemy did not let them forget it.

Every day the aeroplanes went over the lines, and more than once there
was a battle in mid-air above where Ned, Bob and Jerry were on duty.
Once a Hun plane came down in flames, so near they could hear the thud
as it struck.

At times, after a period of comparative quiet, the trenches on both
sides of No Man's Land would suddenly awaken into life. This would be
caused by a fear, either on the part of the Germans or the troops from
America, that one or the other was starting a raid. Then the machine
guns would open fire, they would be augmented by the rifles of the
men, and, if the shooting kept up long enough, the rival batteries
would awaken and the big guns would speak.

It was one day, when the three chums had been on duty in the
front-line trench about a week, that, as they were talking about the
chance of seeing Professor Snodgrass and helping him in his search for
the two girls, something spun past Ned's head with a whine, and, with
a vicious ping, imbedded itself in the trench wall behind him.

"What's that?" exclaimed Bob.

"That sniper again," answered Ned. "That's the closest he's come. We'd
better move, fellows, or he may get one of us."

"A sniper!" exclaimed Jerry. "Has he been taking pot shots at you?"

"Several of 'em. I've tried to get him, but I can't figure out where
he hides. Better move down the trench a bit. He seems to train his gun
on this particular spot."

"Gee!" gasped Bob.

Bob and Jerry had moved up from their ow