he size
of the monolith when he stood at last on the broad step over which this
capstone projected like a roof.

The shadows were deep beneath, and Chet, knowing that he could never
draw himself to the top of the great slab whose under side he could
barely touch, knew also that he must watch from all sides. The shadowed
floor beneath the big stone made a shelter from any watchful eyes out
there in the night; here would be his beat as sentry. He walked slowly
to the side of the pyramid, then around toward the front.

It was the front to Chet because it faced the entrance, the rocky
gateway, where they had come in. He did not expect to find that side in
any way differing from the first. Each side was twenty paces in length;
Chet measured them carefully, astounded still at the size of the
structure.

"Carved by the winds and rains," he said, repeating the opinion of
Professor Kreiss. "Now, I wonder.... It seems too regular, too much as
if--" He paused in his thoughts as he reached the corner; waited to
stare watchfully out into the night; turned the corner, and, still in
shadow, moved on. "Too much as if nature had had some help!"

His meditation ended as abruptly as did his steady pacing: he was
checked in midstride, one foot outstretched, while he struggled for
balance and fought to keep from taking that forward step.

In the shelter of the capstone was a darker shadow; there was a
blackness there that could mean only the opening of a cave--a cavern,
whose regular outlines and square-cut portal dismissed for all time the
thought of a natural opening in the rock. But it was not this alone that
had brought the man up short in his stealthy stride: it had jolted him
as if he had walked head on into the great monolith itself. It was not
this but a flat platform before the cave, a raised stone surface some
two feet above the floor. And on it, pale and unreal in the first light
of the rising Earth was a naked, human form--a face that grimaced with
distorted features.

* * * * *

Chet had known the ape-men on that earlier visit: he knew that while
most of them were heavily covered with hair there were some who were
almost human in their hairlessness. The body before him was one of
these.

It lay limply across the stone platform, the listless head hanging
downward over one edge. It had high cheekbones, a retreating forehead,
glassy, staring eyes, and grinning teeth that projected from betw