are the seats of intellectual life. We marvel still more at the announcement that the systems of the stars are planetary, and inhabited like our own; and our faltering reason utterly fails us when called upon to believe that even the nebulæ must be surrendered to life and reason. Wherever there is matter there must be Life; Life Physical to enjoy its beauties—Life Moral to worship its Maker, and Life Intellectual to proclaim His wisdom and His power.

CHAPTER IX.

CLUSTERS OF STARS AND NEBULE.

AMONG the bodies of the sidereal universe, astronomers have from the earliest ages recognised the existence of clusters of stars and of nebula. The Milky Way indicates by its name that it is of a nebular character; but a nebula, properly so called, is a limited space of light, of various forms and various degrees of brightness in its different parts. Sir William Herschel was the first astronomer who observed this class of phenomena systematically, and who divided the bodies which compose it into six classes,1 namely,

1. Clusters of stars, in which each star is distinctly seen.

2. Resolvable Nebula, or such as excite a

1 We omit the other three classes of planetary nebulæ, stellar nebulæ, and nebular stars, as unconnected with our subject.

1

suspicion that they consist of stars, and which a higher magnifying power may be expected to resolve into separate stars.

3. Nebula, properly so called, in which there is no appearance whatever of stars.

It is very obvious that the language used in the above classification, is intended to support the theory that there is such a thing in the sidereal space as real nebulous matter, or star dust, as it has been almost jocularly called, contradistinguished from a nebulous mass of identically the same appearance which the telescope has resolved into separate stars. The phrases which we have put in italics are certainly incorrect, because any appearance, or any expectation of a nebula not being resolvable, is proved to have been erroneous the moment it is resolved. The classification of nebulæ, therefore, should have been, 1. Nebula that the telescope had resolved; and, 2. Nebulæ that the telescope had not resolved.

Sir William Herschel believed in the existence of purely nebulous matter, or star dust, and what has been called the theory of sidereal aggregation; and since his time it has

been made the basis of wild and extravagant speculations equally incompatible with physical and revealed truth. It is, therefore, of some importance that we should succeed in convincing the reader that the existence of nebulæ not yet resolved, is no proof of the existence of star dust, and that we are entitled to conclude that such nebulæ are clusters of stars,-that each star is the sun of a planetary system, and each planet the residence of life and reason. Each nebula, in short, corresponds with our hill of microscopic infusorial animals,—each system with a cubic inch of its materials, and each planet with a cubic line. If we have seen with our own eyes in the microscope the individual animal-only the ten thousandth part of an inch in size, and if we have seen the hill which is an accumulation of them, need we wonder at nebulæ being stars,—at stars being suns,—and at planets being inhabited ?

As it is now an astronomical fact that nebulæ, which Sir William Herschel, with his finest telescopes, could not resolve, and which had no appearance whatever of being resolvable, have been resolved into distinct stars by the magni

ficent reflectors of Lord Rosse, we are enabled without any hypothetical statements to place the question of the existence of star dust or purely nebulous matter, in its proper aspect ;— that is, we can assign a satisfactory reason to the reader for considering every nebula in the heavens as a cluster of stars which is likely to be resolved by telescopes superior to those of Lord Rosse.

For this purpose, let us suppose seven clusters of stars placed at seven different distances in space, and all of which were regarded as nebulæ before the invention of the telescope. When Galileo applied his little telescope to nebula No. 1, or the nearest of the seven, he observed it to consist of separate stars so distinct that he could count them, and he concluded from their having no parallax, and being at an enormous distance, that each was a gigantic sun. Galileo tries in vain to resolve No. 2, which is at a greater distance, and therefore though he thought that a better telescope would resolve it and all the other five, they still remained as nebulæ in the heavens. Sir Isaac Newton, however, nearly a century later, applies