er? How was he to
know that it had gone straight through? There might be a dozen
different turnings in this tunnel: the submarine could easily tilt
head-on against a jagged rock and puncture her hull. There might be
mines planted directly in their course; he might be swimming straight
into some hideous ambuscade.

He drove these thoughts from his mind. The passage had to be made on
the fickle authority of the senses; and, realizing this, Wells took
the helm into his own hands. Graham was posted at the location chart,
with instructions to report the red light if it showed.

* * * * *

Down below, the Edsel electrics were humming very softly; the men
stood vigilantly at posts. On their brows were little beads of sweat,
and here and there a hand clenched nervously. All knew they were in a
tight place; otherwise they were ignorant of where their commander was
leading them. Occasionally a long, shivering rasp ran through the ship
as her hull nudged the rough tunnel wall. Then the course rudders
would swing gently over; and perhaps, almost immediately, another
grinding cry of rock and steel would come from the other side. Then
would come quickly indrawn breaths as the rudders swung again and the
humming silence droned on.

The scrapings came quite often. Often, too, the motors would go silent
altogether, and the _NX-1_ would rest almost motionless as her
commander felt for an opening. It was a tense, nerve-wringing ordeal.
The silence, the waiting, the dainty scrapings were maddening.

Keith Wells' skin was prickling. He kept only fingertips on the tiny
helm: he was playing that uncanny sixth sense of the submarine
commander. When it misled him, the rasping rock groaned out, scarring
the submarine's smooth skin. Generally, the tunnel was straight; but
each time he heard his ship rub against some exterior obstruction, his
teeth went tight--for who knew but what it might be a mine?

They had penetrated perhaps a half-mile when Graham, eyes steady on
the teleview, reported: "Light growing, sir!"

* * * * *

Wells saw that the screen was filling with a soft, faintly glowing
bluish color. The walls of the tunnel became visible, and he noted
that they were widening out, funnel-like. He dared to increase speed
slightly. Three minutes later he saw that the blue illumination was
seeping from the end of the tunnel. They continued out.

"Thank God, we're through!"