seized me from behind. I whirled, my heart in my mouth.
It was the burly sergeant. "What the hell are you dreaming about,
Renaud? Hop to it. Over there, on that shoring job. Get busy now,
or--" The threat in that unfinished sentence chilled me by its very
vagueness.

My squad was hauling heavy timbers, setting them up where a fault
showed in the rocky roof of the tunnel. I joined them but my thoughts
were a madly whirling chaos.

The pattern was complete now. The long, curving under-water ridge on
Jim's chart--this tunnel was boring through it. Whatever it was that
those tripods projected--a new ray it must be--it was _melting_ a
passage six hundred miles long. Under our rafts, under our fleets,
under our coast defenses--to come up far behind our lines. The ridge
joined the coast just south of New York. Some night, while our
generals slept in smug complacency, all that gray green horde of
wolves would belch forth--from the very earth.

And the Americans would follow Europe into hell!

* * * * *

Five minutes passed. I looked again at the face of the tunnel, drawn
by an irresistible fascination. It had advanced a full quarter of a
mile. Like fog before a cloud-piercing searchlight, the age-old rock
was dissolving before the ray. At this rate America's doom would be
sealed in a week. And I, alone among these thousands, was helpless to
avert the climaxing menace.

A howl of rage came from the sergeant. I turned. A diminutive German,
his face pale green with fatigue, had stumbled and fallen under the
weight of a heavy timber.

The swarthy non-com was kicking him with a cruel boot. "Get up, you;
get up before I brain you!"

The sprawling man looked up, fear staring from his deep-sunk eyes.
"_Aber, ich bin krank._"--"I am sick; I can't stand the work; it is
too _schwer_, too heavy," he faltered.

"Sick?" the Russian roared. "Sick? I'll sick you! You're lazy, too
damned lazy to do a little work. I'm tired of this gold-bricking
around here. I'm going to make an example of you that the rest of you
dogs won't forget in a hurry." His face was purple with rage. He bent,
seized the fallen man and dragged him out from under the crushing
bulk. Then, raising the struggling wretch over his head as lightly as
though he were an infant, he ran forward, toward the ray projectors.

Shriek after shriek pierced the hot air, such howls of utter fear and
agony, as I hope never to hear again. The littl