its relations to the sun were understood that men could correct this
first view. It was not, indeed, until relatively modern times that the
solar system came to be perceived as something independent and widely
detached from the fixed stars system; that the spaces which separate
the members of our own solar family, inconceivably great as they are,
are but trifling as compared with the intervals which part us from the
nearer fixed stars. At this stage of our knowledge men came to the
noble suggestion that each of the fixed stars was itself a sun, each
of the myriad probably attended by planetary bodies such as exist
about our own luminary.

It will be well for the student to take an imaginary journey from the
sun forth into space, along the plane in which extends that vast
aggregation of stars which we term the Milky Way. Let him suppose that
his journey could be made with something like the speed of light, or,
say, at the rate of about two hundred thousand miles a second. It is
fit that the imagination, which is free to go through all things,
should essay such excursions. On the fancied outgoing, the observer
would pass the interval between the sun and the earth in about eight
minutes. It would require some hours before he attained to the outer
limit of the solar system. On his direct way he would pass the orbits
of the several planets. Some would have their courses on one side or
the other of his path; we should say above or below, but for the fact
that we leave these terms behind in the celestial realm. On the margin
of the solar system the sun would appear shrunken to the state where
it was hardly greater than the more brilliant of the other fixed
stars. The onward path would then lead through a void which it would
require years to traverse. Gradually the sun which happened to lie
most directly in his path would grow larger; with nearer approach, it
would disclose its planets. Supposing that the way led through this