generally similar _systems_. [10] It is not _impossible_ that some unlooked-for optical improvement may disclose to us, among innumerable varieties of systems, a luminous sun, encircled by luminous and non-luminous rings, within and without and between which, revolve luminous and non-luminous planets, attended by moons having moons—and even these latter again having moons. Let us now, expanding our conceptions, look upon each of these systems as in itself an atom; which in fact it is, when we consider it as but one of the countless myriads of systems which constitute the Universe. Regarding all, then, as but colossal atoms, each with the same ineradicable tendency to Unity which characterizes the actual atoms of which it consists—we enter at once upon a new order of aggregations. The smaller systems, in the vicinity of a larger one, would, inevitably, be drawn into still closer vicinity. A thousand would assemble here; a million there—perhaps here, again, even a billion—leaving, thus, immeasurable vacancies in space. And if now, it be demanded why, in the case of these systems—of these merely Titanic atoms—I speak, simply, of an “assemblage,” and not, as in the case of the actual atoms, of a more or less consolidated agglomeration:—if it be asked, for instance, why I do not carry what I suggest to its legitimate conclusion, and describe, at once, these assemblages of system-atoms as rushing to consolidation in spheres—as each becoming condensed into one magnificent sun—my reply is that μελλοντα ταυτα—I am but pausing, for a moment, on the awful threshold of _the Future_. For the present, calling these assemblages “clusters,” we see them in the incipient stages of their consolidation. Their _absolute_ consolidation is _to come_. We have now reached a point from which we behold the Universe as a spherical space, interspersed, _unequably_, with _clusters_. It will be noticed that I here prefer the adverb “unequably” to the phrase “with a merely general equability,” employed before. It is evident, in fact, that the equability of distribution will diminish in the ratio of the agglomerative processes—that is to say, as the things distributed diminish in number. Thus the increase of _in_-equability—an increase which must continue until, sooner or later, an epoch will arrive at which the largest agglomeration will absorb all the others—should be viewed as, simply, a corroborative indication of the _tendency to One_. And here, at length, it seems proper to inquire whether the ascertained _facts_ of Astronomy confirm the general arrangement which I have thus, deductively, assigned to the Heavens. Thoroughly, they _do_. Telescopic observation, guided by the laws of perspective, enables us to understand that the perceptible Universe exists as _a cluster of clusters, irregularly disposed_.