were a mystery to Calvin. And as the afternoon
wore on, their conduct as a whole became even more mysterious. It was,
from human standards, totally irrational. One would begin a test,
analysis, or whatever it might be; he would follow it through its
devious windings to its ambiguous result, or to no result, and suddenly
leave it to begin something else, or come to watch the humans perform.

* * * * *

The longer he observed their conduct, the more worried he became.
Finally, after a good bit of hiding and spying, he found out something
which he had been trying to figure for hours; and then it seemed time
for him to talk to someone about their escape.

The blond man had been peering into his briefcase. He zipped it shut
quickly as Calvin approached, with a kind of guilty movement. What does
he have in there? Calvin wondered.

"Mr. Watkins," he said, rubbing his chin and wishing he had a razor,
"did you ever see a scientist, or laboratory assistant, skip from one
thing to another as these creatures do?"

"I never did."

"Nor did I. They don't take care of their equipment, either; several
times one or another has kicked down a neat pile of gear, and once I
distinctly heard something break."

"It might be junked machinery," suggested Watkins.

"I doubt it."

One of the giants made a raucous noise--_Brangg!_

"And how irritable they are, in addition to their capriciousness and
sloppiness! I can't imagine a race of emotional misfits producing
equipment of such complexity. Their science is beyond ours in many ways,
yet look at this place." He made a broad gesture. "When we were let out
this morning, it was clean and well ordered. I've inspected dairies that
were far dirtier. Now it's a hodge-podge of scattered materials, upset
stacks of gear, tipped-over instruments. What sort of mind can bear such
confusion?"

Watkins smiled. "The minds that conceived--well, that vertical maze, for
instance--must be orderly after a fashion, even though it isn't the
human fashion."

"This is far from what I wanted to say, though. Have you been noticing
the door?"

"There isn't much to notice. It's a sliding panel like our wall."

"When one of the creatures leaves, he passes his right hand across what
is evidently an electric eye beam, as nearly as I can place it about ten
or eleven feet off the floor. That opens the door."

"Good going, Cal!" said Watkins. "I hadn't seen 'em do it."

"Our tr