was
continuous, and he took as an illustration the loops on a cord. You
are to think of a cord always looping and unlooping itself according to
certain mathematical laws. Oh, I tell you, I gave up trying to follow
him. And he was so desperately in earnest all the time. By his
account Space was a sort of mathematical pandemonium."

Leithen stopped to refill his pipe, and I mused upon the ironic fate
which had compelled a mathematical genius to make his sole confidant of
a philistine lawyer, and induced that lawyer to repeat it confusedly to
an ignoramus at twilight on a Scotch hill. As told by Leithen it was a
very halting tale.

"But there was one thing I could see very clearly," Leithen went on,
"and that was Hollond's own case. This crowded world of Space was
perfectly real to him. How he had got to it I do not know. Perhaps
his mind, dwelling constantly on the problem, had unsealed some
atrophied cell and restored the old instinct. Anyhow, he was living
his daily life with a foot in each world.

"He often came to see me, and after the first hectic discussions he
didn't talk much. There was no noticeable change in him--a little more
abstracted perhaps. He would walk in the street or come into a room
with a quick look round him, and sometimes for no earthly reason he
would swerve. Did you ever watch a cat crossing a room? It sidles
along by the furniture and walks over an open space of carpet as if it
were picking its way among obstacles. Well, Hollond behaved like that,
but he had always been counted a little odd, and nobody noticed it but
me.

"I knew better than to chaff him, and had stopped argument, so there
wasn't much to be said. But sometimes he would give me news about his
experiences. The whole thing was perfectly clear and scientific and
above board, and nothing creepy about it. You know how I hate the
washy supernatural stuff they give us nowadays. Hollond was well and
fit, with an appetite like a hunter. But as he talked,
sometimes--well, you know I haven't much in the way of nerves or
imagination--but I used to get a little eerie. Used to feel the solid
earth dissolving round me. It was the opposite of vertigo, if you
understand me--a sense of airy realities crowding in on you-crowding
the mind, that is, not the body.

"I gathered from Hollond that he was always conscious of corridors and
halls and alleys in Space, shifting, but shifting according to
inexorable laws. I never