moved with jerky motions and clattered and
snarled.

"There is probably more to _them_ in another dimension," Ione said.

* * * * *

Suddenly one of the beasts approached them with a leap. There were two
big eyes and two rows of teeth that came together with a snap, right
on Phil's trouser-leg. He jerked himself away, sacrificing some square
inches of trouser-leg, and, whirling around, kicked at the thing with
all his force. It almost paralyzed his foot, for the animal seemed to
be made of wood or bone. But it disappeared, and, as it did, both of
them felt a queer, nauseating jolt. A few more minutes' walk brought
them back to the safe without seeing any more spaces; and the sight of
its black iron bulk filled them with a home-like relief, which in a
moment they recognized as a mockery.

"Are we on a sphere of some sort?" Phil asked.

"Probably on an irregular mass of matter," Ione replied, "part of
which is Tony's concrete floor, and part of which comes out of some
other dimension. This mass of matter is at one end of a long, bar-like
portion of space, the middle of which is pivoted in our world,
somewhere in Chicago, and both ends of which are free in hyperspace."

"Then," suggested Phil, "why can't we walk down to the axle on which
it is balanced, and step out into Chicago?"

"Because there isn't any _matter_ for us to walk on. We are not able
to move about in space, in three dimensions, you know. We can only get
around in two dimensions, on the surface of _matter_."

"Well, let's try another exploration trip at right angles to our first
one. After all, these 'spaces' are an interesting show, and I want to
see some more."

They started out in the selected direction, and after a short walk got
a glimpse of a vast space dotted with stars and nebulae, with two
bright moons sailing overhead. A few steps farther on was a wall of
solid granite, near enough to touch with their hands. Again, there was
an intensely active mass of weaving bright stripes and loops and
circles, seeming to consist of light only, and making them dizzy in a
few seconds. Ione wondered if it might not be something like an
organic molecule on a large scale. Again, odd, queer, indescribable
shapes and outlines would appear and disappear, obviously
three-dimensional sections of multi-dimensional things, cut by space.
Once they passed a place of intense cold and terrific noise and
escaped destruction or lunacy o