"By means of translucent shells illuminated from behind. The stars, of
course, are electric lamps, and some of them, as you see, have a tinge
of red or blue."

Most of the light, however, came from a brilliant globe of a bluish
lustre, which appeared to occupy the centre of the crystal sphere, and
was surrounded by a number of smaller and fainter orbs that shone by its
reflected rays.

"This, again, is a model of the solar system," said Gazen. "The central
luminary is, of course, the sun, and the others are the planets with
their satellites."

"They seem to float in air."

"That is because their supports are invisible, or nearly so. Both their
lights and periodic motions are produced by the electric current."

"Surely they are not moving now?"

"Oh, yes, and with velocities proportionate to those of the real bodies;
but you know that whilst the actual movements of the sun and planets are
so rapid, the dimensions of the system are so vast that if you could
survey the whole from a standpoint in space, as we are supposed to do,
it would appear at rest. Let us look at them a little closer."

I followed Gazen along the gangway which encircled the orrery, and
allowed us to survey each of the planets closer at hand.