r those orbs which lie in our
neighbourhood. The sun has set, the moon has not risen; a cloudless sky
discloses a heaven glittering with countless gems of light. Some are
grouped together into well-marked constellations; others seem scattered
promiscuously, with every degree of lustre, from the very brightest down
to the faintest point that the eye can just glimpse. Amid all this host
of objects, how are we to identify those which lie nearest to the earth?
Look to the west: and there, over the spot where the departing sunbeams
still linger, we often see the lovely evening star shining forth. This
is the planet Venus--a beauteous orb, twin-sister to the earth. The
brilliancy of this planet, its rapid changes both in position and in
lustre, would suggest at once that it was much nearer to the earth than
other star-like objects. This presumption has been amply confirmed by
careful measurements, and therefore Venus is to be included in the list
of the orbs which constitute our neighbours.

Another conspicuous planet--almost rivalling Venus in lustre, and
vastly surpassing Venus in the magnificence of its proportions and its
retinue--has borne from antiquity the majestic name of Jupiter. No doubt
Jupiter is much more distant from us than Venus. Indeed, he is always at
least twice as far, and sometimes as much as ten times. But still we
must include Jupiter among our neighbours. Compared with the host of
stars which glitter on the heavens, Jupiter must be regarded as quite
contiguous. The distance of the great planet requires, it is true,
hundreds of millions of miles for its expression; yet, vast as is that
distance, it would have to be multiplied by tens of thousands, or
hundreds of thousands, before it would be long enough to span the abyss
which intervenes between the earth and the nearest of the stars.

Venus and Jupiter have invited our attention by their exceptional
brilliancy. We should, however, fall into error if we assumed generally
that the brightest objects were those nearest to the earth. An observer
unacquainted with astronomy might not improbably point to the Dog
Star--or Sirius, as astronomers more generally know it--as an object
whose exceptional lustre showed it to be one of our neighbours. This,
however, would be a mistake. We shall afterwards have occasion to refer
more particularly to this gem of our southern skies, and then it will
appear that Sirius is a mighty globe far transcending our own sun in
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