the solar system, it is only one of an infinity of others which may be
still more extensive. Our sun is supposed to be a star belonging to a
constellation of stars, each of which has its accompaniment of revolving
planets; and the constellation itself with similar constellations to
form revolving clusters round some mightier centre of attraction; and so
on, each astral combination increasing in number, magnitude, and
complexity, till the mind is utterly lost in the vain effort to grasp
the limitless arrangement.

Of the stars astronomers can hardly be said to know anything with
certainty. Sirius, which is the most lustrous, was long supposed to be
the nearest and most within the reach of observation, but all attempts
to calculate the distance of that luminary have proved futile. Of its
inconceivable remoteness some notion may be formed by the fact, that the
diameter of the earth's annual orbit, if viewed from it, would dwindle
into an invisible point. This is what is meant by the stars not having,
like the planets, a _parallax_; that is, the earths' orbit, as seen from
them, does not subtend a measurable angle. With two other stars,
however, astronomers have unexpectedly and recently been more fortunate
than with Sirius, and have been able to calculate their distances from
the earth. The celebrated BESSEL, and soon afterwards, the late Mr.
HENDERSON, astronomer royal for Scotland, were the first to surmount the
difficulty that had baffled the telescopic resources of the HERSCHELS.
BESSEL detected a parallax of one-third of a second in the star 61
Cygni, and in the constellation of the Centaur HENDERSON found another
star whose parallax amounted to one second. Of the million of fixed
glittering points that adorn the sky, these are the only two whose
distances have been calculated, and to express them, miles, leagues, or
orbits seems inadequate. Light, whose speed is known to be 192,000 miles
per second, would be three years in reaching our earth from the star of