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bodies in sight of each other. Can we indeed conceive a distance at which it will not act, and show some results, if time be allowed? A centrifugal force then is wanted, and that force, within our system, acts in a circle, and in one case in a complete ring. Is it not, therefore, probable that the Milky Way is a ring of this nature, revolving with a velocity to counteract the tendency of the ring to approximate towards the centre ?
But even if we suppose this, we have not arrived at the end of all astronomical systems and motions. This very revolution of the Milky Way, carrying our sun along with it as a small component part of one side of its circumference, may be nothing but a drop in another ocean of space, that larger one having the same universal rule of rotatory motion to prevent collapse. The immense labour that has of late been bestowed in resolving nebulous stars would seem to explain them by the supposition of each nebula having a system analogous to our own in the large measure of appropriation we have just adopted. Some of these are even annular, as if exactly similar, but many varieties also exist. This number is immense, and their variety in kind equally great.
• It is to Sir William Herschel that we owe the most complete analysis of the great variety of those objects which are generally classed under the common head of Nebulæ, but which have been separated by him intoIst. Clusters of stars, in which the stars are clearly distinguishable; and these, again, into globular and irregular clusters: 2d. Resolvable nebulæ, or such as excite a suspicion that they consist of stars, and which any increase of the optical power of the telescope may be expected to resolve into distinct stars: 3d. Nebulæ, properly so called, in which there is no appearance whatever of stars; which, again, have been subdivided into subordinate uses, according to their brightness and size: 4th. Planetary nebulæ : 5th. Stellar nebulæ: and 6th. Nebulous stars. The great power of his telescopes disclosed the existence of an immense number of these objects before unknown, and showed them to be distributed over the heavens, not by any means uniformly, but with a marked preference to a certain district, extending over the northern pole of the galactic circle, and occupying the constellations Leo, Leo Minor, the body, tail, and hind legs of Ursa Major, Canes Venatici, Coma Berenices, the preceding leg of Bootes, and the head, wings, and shoulder of Virgo. In this region, occupying about one-eighth of the whole surface of the sphere, one-third of the entire nebulous contents of the heavens are congregated. On the other hand, they are very sparingly scattered over the constellations Aries, Taurus, the head and shoulders of Orion, Auriga, Perseus, Camelopardalus, Draco, Hercules, the northern part of Serpentarius, the tail of Serpens, that of Aquila, and the whole of Lyra. The hours 3, 4, 5, and 16, 17, 18, of right ascension in the northern hemisphere are singularly poor, and, on the other hand, the hours 10, 11, and 12 (but especially 12), extraordinarily rich in these objects. In the southern hemisphere a much greater uniformity of distribution prevails, and with exception of two very remarkable centres of accumulation, called the Magellanic clouds (of which more presently), there is no very decided tendency to their assemblage in any particular region.'-Pp. 595, 596.
A common appearance of nebulæ, as seen through a high magnifying power, is as follows:
"They are then, for the most part, perceived to consist entirely of stars crowded together so as to occupy almost a definite outline, and to run up to a blaze of light in the centre, where their condensation is usually the greatest. Many of them, indeed, are of an exactly round figure, and convey the complete idea of a globular space filled full of stars, insulated in the heavens, and constituting in itself a family or society apart from the rest, and subject only to its own internal laws. It would be a vain task to attempt to count the stars in one of these globular clusters. They are not to be reckoned by hundreds ; and on a rough calculation, grounded on the apparent intervals between them at the borders, and the angular diameter of the whole group, it would appear that many clusters of this description must contain, at least, five thousand stars, compacted and wedged together in a round space, whose angular diameter does not exceed eight or ten minutes; that is to say, in an area not more than a tenth part of that covered by the moon.'— Pp. 592, 593.
Other appearances show the freaks of Nature and the wonderful variety of her designs :
• Viewed with an 18-inch reflector, no part of this strange object shows any sign of resolution into stars, nor in the brightest and most condensed portion adjacent to the singular oval vacancy in the middle of the figure is there any of that curdled appearance, or that tendency to break up into bright knots with intervening darker portions which characterise the nebula of Orion, and indicate its resolvability. The whole is situated in a very rich and brilliant part of the Milky Way, so thickly strewed with stars that in the area occupied by the nebula, not less than 1200 have been actually counted, and their places in R. A. and P. D. determined. Yet it is obvious that these have no connexion whatever with the nebula, being, in fact, only a simple continuation over it of the general ground of the galaxy, which on an average of two hours in Right Ascension in this period of its course contains no less than 3138 stars to the square degree, all, however, distinct, and (except where the object in question is situated) seem projected on a perfectly dark heaven, without any appearance of intermixed nebulosity. The conclusion can hardly be avoided, that in looking at it we see through, and beyond the Milky Way, far out into space, through a starless region, disconnecting it altogether from our system. “It is not easy for language to convey a full impression of the beauty and sublimity of the spectacle which this nebula offers, as it enters the field of view of a telescope fixed in Right Ascension, by the diurnal motion, ushered in as it is by so glorious and innumerable a procession of stars, to which it forms a sort of climax," and in a part of the heavens otherwise full of interest. One other bright and very remarkably formed nebula of considerable magnitude precedes it nearly ou the same parallel, but without any traceable connexion between them.'-—Pp. 610, 611.
We will conclude our extracts with a description of the Magellanic clouds :
• The Magellanic clouds, or the nubeculæ (major and minor), as they are called in the celestial maps and charts, are, as their name imports, two nebulous or cloudy masses of light, conspicuously visible to the naked eye, in the southern hemisphere, in the appearance and brightness of their light not unlike portions of the Milky Way of the same apparent size. They
are, generally speaking, round, or somewhat oval, and the larger, which deviates most from the circular form, exhibits the appearance of an axis of light, very ill defined, and by no means strongly distinguished from the general mass, which seems to open out at its extremities into somewhat oval sweeps, constituting the preceding and following portions of its circumference. A small patch, visibly brighter than the general light around, in its following part, indicates to the naked eye the situation of a very remarkable nebula (No. 30. Dorâdus of Bode's catalogue), of which more hereafter. The greater nubecula is situated between the meridians of 4h 40m and 6h Om and the parallels of 156o and 162° of N. P. D., and occupies an area of about 42 square degrees. The lesser, between the meridians 0h 28m and 1h 15m and the parallels of 162o and 165° N. P.D., covers about ten square degrees. Their degree of brightness may be judged of from the effect of strong moonlight, which totally obliterates the lesser, but not quite the greater.'
. When examined through powerful telescopes, the constitution of the nubeculæ, and especially of the nebecula major, is found to be of astonishing complexity. The general ground of both consists of large tracts and patches of nebulosity in every stage of resolution, from light, irresolvable with 18 inches of reflecting aperture, up to perfectly separated stars like the Milky Way, and clustering groups sufficiently insulated and condensed to come under the designation of irregular, and in some cases pretty rich clusters. But besides those, there are also nebulæ in abundance, both regular and irregular; globular clusters in every state of condensation ; and objects of a nebulous character quite peculiar, and which have no analogue in any other region of the heavens. Such is the concentration of these objects, that in the area occupied by the nebecula major, not fewer than 278 nebulæ and clusters have been enumerated, besides 50 or 60 outliers, which considering the general barrenness in such objects of the immediate neighbourhood) ought certainly to be reckoned as its appendages, being about 6) per square degree, which very far exceeds the average of any other, even the most crowded parts of the nebulous heavens. In the nebeculæ minor, the concentration of such objects is less, though still very striking, 37 having been observed within its area, and 6 adjacent, but outlying. The nebeculæ, then, combine, each within its own area, characters which in the rest of the heavens are
no less strikingly separated,—viz. those of the galactic and the nebular system. Globular clusters (except in one region of small extent) and nebulæ of regular elliptic forms are comparatively rare in the Milky Way, and are found congregated in the greatest abundance in a part of the heavens, the most remote possible from that circle; whereas, in the nebeculæ, they are indiscriminately mixed with the general starry ground, and with irregular though small nebulæ,'— Pp. 613, 614.
And now let us ask, before we close the subject of Astronomy, what is its place and office as a study of the human intellect? It is commonly said, that the wonders of creation teach us to look from nature to nature's God, and so they do; but this is too abstract and indefinite a phrase to convey any practical idea of utility. We would like also to know the process by which such physical knowledge leads to religious impressions. If the conclusion is expected to be arrived at forthwith without any doubt or hesitation, we cannot encourage such sanguine hopes of the benefits of science. The direct inference from creation
NO, LXVII.- N.S.
to a Creator does not bring us sufficiently in connexion with the distinctive doctrines of Christian revelation to have much influence as a direct motive in the conduct of a Christian's life, or the establishment of his faith. Conclusions from physical reasoning have, we think, very little to do in any immediate relation with those feelings of the heart which constitute the Christian's state of mind. By Astronomy, therefore, we do not expect to convert the infidel, or materially to settle the mind of a sceptic, neither would we look to it as a reformer of morals except so far as it may, in common with other intellectual pursuits and interests,
• Emollit mores, nec sinit esse feros.' Yet Astronomy has an important religious and moral purpose to accomplish in the world, and is capable of adding much to man's perception of the glory of God if viewed in its proper light, and not required to accomplish what was never intended of it.
What, then, is the religious use and purpose of Astronomy if we slight its influence over the reasoning powers? It is comprehended in the word praise. The more a Christian knows of God's works, the more instruments of praise does he possess, and the more widely does he feel his common interest with all things visible and invisible, to give glory and honour and praise to the Almighty Maker of Heaven and Earth. 'O praise the • Lord of heaven,' saith the Psalmist : 'praise him in the height. · Praise him, sun and moon : praise him, all ye stars and light. * Praise him, all ye heavens : and ye waters that are above the 'heavens. Let them praise the Name of the Lord : for he spake 'the word, and they were made; he commanded, and they were created. He made them fast for ever and ever: he
them a law which shall not be broken.'
But in the guidance of morals, astronomy has its specific use, which is none the less important, because we curtail it of a certain vapid generality popularly attributed to it. We take the laws of physical astronomy, if understood, to be a natural antidote in the human mind to the confusion, the irregularity, and discord of all sublunary plans and earthly governments. After witnessing the strife of tongues, whether in the senate, in the public places of resort and business, or in the domestic hearth, what more solemn contrast can be imagined, one calculated to sink deeper into the mind, than the contemplation of that awful silence, that gigantic power and unerring rectitude shown in the laws and circuits of heavenly bodies. Physical disorder is here met by physical order, and a field is open for the latter to attune the harsh discord of the former, to subdue the fretting
vicissitudes of thought and feeling that pass over us, by making us look on the mighty roll of time; to soften the asperities of the heart, by reminding us of the smallness and humility of our outward actions, when viewed in conjunction with the great yet peaceful works of heaven. 'Supra spharam lunæ non est malum,' was a saying of the Schoolmen.
In thus marking out the uses of astronomy under the heads of praise, and a moral example of rule and order, we are not only safe against all deistical exaltation of science and physics that some popular modes of talking would encourage, but we have the authority of many early devotional writers of the Church for a very abundant introduction of such objects and such lessons as this science instructs us of, into religious exercises themselves.