this cave was much larger, wider than the other. He stood
in the opening, slowly swung the beam of his torch around the smooth
walls, still holding Digger, who, by now, was indicating that he'd like
to be set down. Nat released him unthinkingly, his mind fully taken up
with what the light revealed.

* * * * *

Spaceships! The room was packed with them--all sizes, old and new. A
veritable sargasso. At first, he thought they might be craft belonging
to nameless inhabitants of this world, but, as he approached them, he
recognized Terrestrial identifications.

The first was a scout ship of American Spaceways! Nat recognized the
name: _Ceres_, remembered a telecast account of its disappearance in
space. There was a neat little reward for information as to its
whereabouts. Nat's lips curled in derision: it wouldn't equal the
expense of his journey out here. There was a deep groove in the smooth
material of the floor where the ship had been dragged through the
doorway into the room. What machines could have done this work without
leaving their own traces? He went to the other ships: all were small,
mostly single or two-passenger craft. The last entry in the logs of
many was to the effect that they were about to land on the Asteroid
Moira to rescue a girl held captive there.

None had crashed; all ships were in perfect order. But all were
deserted. Two doors were gone from the interior of one of the vessels.
They might have been removed for any of a hundred reasons--but why
here?

Nat's glance swept the room, came to rest on the figure of a heavy duty
robot of familiar design. Semi-human in form, it looked like some
misshapen, bent, headless giant. He inspected it: _Meyers Robot, Inc._
Earth designed for mining operations on Mars.

"Well, Digger, I can see now how these ships were brought in here; that
robot could move any one of these with ease. But that doesn't explain
where the humans have gone. It might be space pirates using this
asteroid for a base, or it might be some alien form of life. We're
still free. Shall we beat it or stay and try to check this out?"

He did not know how much of this got over to the spacehound, but the
impressions he received in answer were those of approving their
remaining where they were.

"I suppose the best system is to explore the rest of the caves in
order; let's go."

Followed by Digger, he walked quietly toward the next cave on the left,