However, I reasoned that a light diet is conducive to good brain work,
and as I later learned, the object of this systematic weight control was
not alone to save food but to increase mental efficiency, for a fat man
is phlegmatic and a lean one too excitable for the best mental output.
It would also help my disguise by keeping me the exact weight and build
of the original Karl Armstadt.

After a fortnight of study, I felt that I was now ready to take up my
work in the laboratory, but I feared my lack of general knowledge of the
city and its ways might still betray me. Hence I began further
journeyings about the streets and shops of those levels where a man of
my class was permitted to go.

~4~

After exhausting the rather barren sport of walking about the monotonous
streets of the four professional levels I took a more exciting trip down
into the lower levels of the city where the vast mechanical industries
held sway. I did not know how much freedom might be allowed me, but I
reasoned that I would be out of my supposed normal environment and hence
my ignorance would be more excusable and in less danger of betraying me.

Alighting from the elevator, I hurried along past endless rows of heavy
columns. I peered into the workrooms, which had no enclosing walls, and
discovered with some misgiving that I seemed to have come upon a race of
giants. The men at the machines were great hulking fellows with thick,
heavy muscles such as one would expect to see in a professional wrestler
or weight-lifter. I paused and tried to gauge the size of these men: I
decided that they were not giants for I had seen taller men in the outer