skin--and now the car shot down while the rising air rushed by us with a
whistling roar.

On the return trip I called my floor as I had heard others do and was
let off at the medical level. It was even more monotonously quiet than
the chemical level, save for the hurrying passage of occasional
ambulances on their way between the elevators and the various hospitals.
The living quarters of the physicians were identical with those on the
chemists' level. So, too, were the quiet shops from which the physicians
supplied their personal needs.

Standing before one of these I saw in a window a new book entitled
"Diseases of Nutrition." I went in and asked to see a copy. The book
seller staring at my chemical uniform in amazement reached quickly under
the counter and pressed a button. I became alarmed and turned to go out
but found the door had been automatically closed and locked. Trying to
appear unconcerned I stood idly glancing over the book shelves, while
the book seller watched me from the corner of his eye.

In a few minutes the door opened from without and a man in the uniform
of the street guard appeared. The book seller motioned toward me.

"Your identification folder," said the guard.

Mechanically I withdrew it and handed it to him. He opened it and
discovered the card from the hospital. Smiling on me with an air of
condescension, he took me by the arm and led me forth and conducted me
to my own apartment on the chemical level. Arriving there he pushed me
gently into a chair and stepped toward the switch of the telephone.