that the sky-car resumed its descent.

They sank down until they were on a level with the top of one of those
extraordinary sky-scrapers. The roof seemed perfectly flat, except for a
large, round, black opening in its center. No one was in sight.

When opposite the upper row of windows, at a distance of perhaps twenty
feet, Smith brought the car to a halt, and they peered in. There were no
panes; the windows opened directly into a vast room; but nothing was
clearly visible in the blackness save the outlines of the opening in the
opposite walls.

They went down further, keeping well to the middle of the space above
the street. At every other yard they kept a sharp lookout for the
inhabitants; but so far as they could see, their approach was entirely
unobserved.

When within fifty yards of the surface, all four men made a search for
cross-wires below. They saw none; there were no poles, even. Neither, to
their astonishment, was there such a thing as a sidewalk. The street
stretched, unbroken by curbing, from wall to wall and from corner to
corner.

As the cube settled slowly to the ground, the adventurers left the
deadlight to use the windows. For a moment the view was obscured by a
swirl of dust, raised by the spurt of the current; then this cloud
vanished, settling to the ground with astounding suddenness, as though
jerked down by some invisible hand.

Directly ahead of them, distant perhaps a hundred yards, lay a