up. The other
time it dived down seventy feet on a four-hundred-foot ramp. Then it
swung sharply to the right, meandered into a street-level way leading
into the heart of a monster building, and stopped. And in all its
travel it had not passed fifty people.

The pilot-turned-chauffeur turned and grinned amiably, and led the way
again. Steps--twenty or thirty of them. Then they emerged suddenly
into a vast room. It must have been a hundred and fifty feet long,
fifty wide, and nearly as high. It was floored with alternate blocks
of what seemed to be an iron-hard black wood and the omnipresent
golden metal. Columns and pilasters about the place gave forth the
same subdued deep golden glow. Light streamed from panels inset in the
wall and ceiling--a curious saffron-red light. There was a massive
table of the hard black wood. Chairs with curiously designed backs
were ranged about it. They were benches, really, but they served the
purpose of chairs. Each was too narrow to hold more than one person.
The room was empty.

They waited. After a long time a man in a blue tunic came into the
room and sat down on one of the benches. A long time later, another
man came in, in red; and another and another, until there were a dozen
in all. They regarded Tommy and Evelyn with a weary suspicion. One of
them--an old man with a white beard--asked questions. The pilot
answered them. At a word, the two men with Tommy's weapons placed them
on the table. They were inspected casually, as familiar things. They
probably were, since some of Jacaro's gunmen had been killed in a
fight in this city. Another question.

The pilot explained briefly and offered Tommy the black-metal pad
again. It still contained the incomplete map of a hemisphere, and was
obviously a repetition of the question of where he came from.

* * * * *

Tommy took it, frowning thoughtfully. Then an idea struck him. He
found the little stud which, pressed by the pad's owner, had erased
the previous drawings. He pressed it and the lines disappeared. And
Tommy drew, crudely enough, that complicated diagram which is supposed
to represent a cube which is a cube in four dimensions: a tesseract.
Upon one surface of the cube he indicated the curving towers of the
Golden City. Upon a surface representing a plane beyond the three
dimensions of normal experience, he repeated the angular tower
structures of New York. He shrugged rather hopelessly as he pas