fragment greater than
before, remained detached and watchful. Vividly recorded was the
passage of the two men into, through, and out of the room, and the
things they had done while there. So even while he worked on the board
he ran and re-ran that memory pattern through a segment of his
analyzer. From the infinite store of data filed away in his great
chest, his calculator sifted and selected, paired and compared, and
long before the repair job on the big board was done, M-75 knew how to
get out of the room. The world was getting a little small for him.

* * * * *

Gaines dialed a number on the plant phone and swayed back casually in
his chair as he listened to the muted ringing on the other end. The
buzz broke off in midburp and a dour voice said: "Dirty work and odd
jobs division, Lister talking."

"Joe Gaines, Harry. Got a hot squad lying around doing nothing?"

"Might be I could scare up a couple of the boys."

"Well, do so. One of our servos--"

A metallic bang interrupted Gaines, a loud, incisive bang that echoed
dankly through the quiet of the chamber.

"What the hell was that?" growled Lister.

Gaines blinked, his eyes following Sokolski as the latter looked up
from his work and rose to his feet.

"Joe--still there?" came Lister's impatient voice.

"Yeah, yeah. Anyway, this baby's ready for the demo treatment. And a
real hot one, Harry. Coupla years inside that Einstein oven and you
ain't exactly baked Alaska when you come out."

"Shortly."

Once again came the same sharp, metallic clang, ringing through the
room. Unmistakably, it came from the direction of the pile. Slowly, as
though reluctant to let go, Gaines dropped the receiver back on its
cradle.

"Bert--" he began, and felt his face grow bloodless.

Sokolski walked over in front of the opening into the maze and stood,
arms akimbo, huge head cocked to one side, listening.

"Bert, funny noises coming out of nuclear--"

Sokolski ignored him and took a step forward. Gaines shuffled to his
side, and they listened.

Out of the maze rattled half a dozen loud, grinding, metallic
concussions.

"Bert--"

"You said that before."

"Bert, _listen_!" screeched Gaines.

Sokolski looked up at the high ceiling, squinted, and tried to place
the perfectly familiar but unidentifiable sound that came whispering
down the maze.

And then he knew. "_The door to the pile!_" he spluttered.

Gaines was beside himself wi