_along_ the lines of the Y--but when, looking out into
the general Heaven, he turns his eyes _from_ the Galaxy, he is then
surveying it in the direction of the letter's thickness; and on this
account the stars seem to him scattered; while, in fact, they are as
close together, on an average, as in the mass of the cluster. _No_
consideration could be better adapted to convey an idea of this
cluster's stupendous extent.

If, with a telescope of high space-penetrating power, we carefully
inspect the firmament, we shall become aware of _a belt of clusters_--of
what we have hitherto called "nebulae"--a _band_, of varying breadth,
stretching from horizon to horizon, at right angles to the general
course of the Milky Way. This band is the ultimate _cluster of
clusters_. This belt is _The Universe_. Our Galaxy is but one, and
perhaps one of the most inconsiderable, of the clusters which go to the
constitution of this ultimate, Universal _belt_ or _band_. The
appearance of this cluster of clusters, to our eyes, _as_ a belt or
band, is altogether a perspective phaenomenon of the same character as
that which causes us to behold our own individual and roughly-spherical
cluster, the Galaxy, under guise also of a belt, traversing the Heavens
at right angles to the Universal one. The shape of the all-inclusive
cluster is, of course _generally_, that of each individual cluster which
it includes. Just as the scattered stars which, on looking _from_ the
Galaxy, we see in the general sky, are, in fact, but a portion of that
Galaxy itself, and as closely intermingled with it as any of the
telescopic points in what seems the densest portion of its mass--so are
the scattered "nebulae" which, on casting our eyes _from_ the Universal
_belt_, we perceive at all points of the firmament--so, I say, are these
scattered "nebulae" to be understood as only perspectively scattered, and
as part and parcel of the one supreme and Universal _sphere_.

No astronomical fallacy is more untenable, and none has been more
pertinaciously adhered to, than that of the absolute _illimitation_ of
the Universe of Stars. The reasons for limitation, as I have already
assigned them, _a priori_, seem to me unanswerable; but, not to speak of
these, _observation_ assures us that there is, in numerous directions
around us, certainly, if not in all, a positive limit--or, at the very
least, affords us no basis whatever for thinking otherwise. Were the
succession of stars endl