The Building of the sphere

I remember the occasion very distinctly when Cavor told me of his idea of
the sphere. He had had intimations of it before, but at the time it seemed
to come to him in a rush. We were returning to the bungalow for tea, and
on the way he fell humming. Suddenly he shouted, "That's it! That
finishes it! A sort of roller blind!"

"Finishes what?" I asked.

"Space--anywhere! The moon."

"What do you mean?"

"Mean? Why--it must be a sphere! That's what I mean!"

I saw I was out of it, and for a time I let him talk in his own fashion. I
hadn't the ghost of an idea then of his drift. But after he had taken tea
he made it clear to me.

"It's like this," he said. "Last time I ran this stuff that cuts things
off from gravitation into a flat tank with an overlap that held it down.
And directly it had cooled and the manufacture was completed all that
uproar happened, nothing above it weighed anything, the air went squirting
up, the house squirted up, and if the stuff itself hadn't squirted up too,
I don't know what would have happened! But suppose the substance is loose,
and quite free to go up?"

"It will go up at once!"