of the forest at a distance,
but are unable to distinguish the individual trees. Besides this mass of
stars to which our solar system belongs, there are thousands of smaller
similar clouds in various parts of the heavens, which have successively
been shown to consist of multitudes of stars. But all around these
star-clouds the clear blue sky is discovered by the naked eye.

Now, it is easy to perceive, that if all the regions of infinite space
were filled either with self-luminous suns, or planets capable of
reflecting light, or luminous nebulae, or comets of gaseous consistency,
at such distances as the Milky Way, or any other star-cloud demonstrates
to be safe and practicable, we should see no blue sky at all; but the
whole vault of heaven would present that whitish light resulting from
the mingling of the rays of multitudes of stars, planets, and comets,
which the Milky Way does actually exhibit. No matter how small or how
distant these stars, _if they were only infinitely numerous_, it is
impossible that there could be any point in the heavens unilluminated by
their rays, even although the stars themselves were invisible to our
eyes, or even to our telescopes. The whole heaven would be one vast
Milky Way. Or rather, as Humboldt reasons, "If the entire vault of
heaven were covered with innumerable strata of stars, one behind the
other, as with a widespread starry canopy, and light were undiminished
in its passage through space, the sun would be distinguished only by its
spots, the moon would appear as a dark disc, and amid the general blaze
not a constellation would be visible."[186] It would appear also to
follow, as a necessary consequence, that such an infinite multitude of
blazing suns must generate a heat compared with which the general
conflagration would be cool and comfortable.

But the telescope shows us a state of matters vastly different from
this. It shows us, in fact, that space, so far from being occupied with
suns and stars, is mostly empty. Our universe is only a little island in
the great ocean of infinite space.

Though the telescope discovers multitudes of stars where the naked eye
sees none, yet they are, in far the greater number of instances, "_seen
projected on a perfectly dark heaven, without any appearance of
intermixed nebulosity_."[187] And even through the Milky Way, and the
other nebulae, the telescope penetrates, through "_intervals absolutely
dark, and completely void of any star, of