stance of the fixed stars--of any
one of the myriads of suns glistening on the farther side of that awful
chasm which separates our system from its brothers in the cluster to
which it belongs--astronomical science, until very lately, could speak
only with a negative certainty. Assuming the brightest as the nearest,
we could say, even of _them_, only that there is a certain
incomprehensible distance on the _hither_ side of which they cannot
be:--how far they are beyond it we had in no case been able to ascertain.
We perceived, for example, that Alpha Lyrae cannot be nearer to us than
19 trillions, 200 billions of miles; but, for all we knew, and indeed
for all we now know, it may be distant from us the square, or the cube,
or any other power of the number mentioned. By dint, however, of
wonderfully minute and cautious observations, continued, with novel
instruments, for many laborious years, _Bessel_, not long ago deceased,
has lately succeeded in determining the distance of six or seven stars;
among others, that of the star numbered 61 in the constellation of the
Swan. The distance in this latter instance ascertained, is 670,000 times
that of the Sun; which last it will be remembered, is 95 millions of
miles. The star 61 Cygni, then, is nearly 64 trillions of miles from
us--or more than three times the distance assigned, _as the least
possible_, for Alpha Lyrae.

In attempting to appreciate this interval by the aid of any
considerations of _velocity_, as we did in endeavoring to estimate the
distance of the moon, we must leave out of sight, altogether, such
nothings as the speed of a cannon-ball, or of sound. Light, however,
according to the latest calculations of Struve, proceeds at the rate of
167,000 miles in a second. Thought itself cannot pass through this
interval more speedily--if, indeed, thought can traverse it at all. Yet,
in coming from 61 Cygni to us, even at this inconceivable rate, light
occupies more than _ten years_; and, consequently, were the star this
moment blotted out from the Universe, still, _for ten years_, would it
continue to sparkle on, undimmed in its paradoxical glory.

Keeping now in mind whatever feeble conception we may have attained of
the interval between our Sun and 61 Cygni, let us remember that this
interval, however unutterably vast, we are permitted to consider as but
the _average_ interval among the countless host of stars composing that
cluster, or "nebula," to which our system,