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THE SNOW MAN.
Spite of the incle
mency of the season, and more particularly in consequence of it, this is a time of much vigorous and healthful out-of-door exercise, in which holiday schoolboys take no small share. They have snow-balling, and snow-man making, to say nothing of skating and sliding; but though we may not say much about them, some of our poets have done so, and that right pleasantly.
And in the frosty season, when the sun
The village-clock toll'd six. I wheel'd about,
So through the darkness and the cold, we flew,
Not seldom from the uproar I retired
Glanced sideway, leaving the tumultuous throng,
Image, that flying still before me, gleam'd
THE MILKY WAY. After all these cheerful Christmas doings, good dinners, and merry dances, there often comes the return home across snowy country, ard beneath the brilliant winter heavens. At such times it cannot be wholly out of place to direct the mind towards the most sublime and glorious objects of creation, the starry hosts which the darkness of night reveals. In speaking of the Milky Way, and those most mysterious of celestial phenomena, the Nebulæ, as revealed to us by Lord Rosse's telescope, Professor Nichols says,—Let us follow in the track of Herschel, and meditate on the comparative shapes and interior characteristics of such Nebulæ as have been most closely examined. With caution indeed! For the greatest telescope of Parsonstown can speak but hesitatingly regarding the habitudes of these stupendous masses. I shall refer only to the two principal forms.
Looking attentively at the spherical clusters, Sir William Herschel discerned among them, a marked and regular progression in reference to their essential features ; and also among the non-essential, a striking congruity with the conclusion which the general aspect of these clusters had induced him to accept. It appeared to this great observer that, in so far as the arrangement of light is concerned, a number of small spheres might be arranged, each slightly brighter at the centre than the one preceding it, which could safely be taken, each as the representative or type of a numerous class of stellar clusters. But besides such mere gradation, the irregular branches of these nebulæ, the filaments attached to them, all concur towards the result of our great astronomer's thoughts. There are,” as he says himself, "additional circumstances in the appearance of extended clusters which very much favour the idea of a power lodged in the brightest part. Although the form of these be not globular, it is plainly to be seen that there is a tendency towards sphericity, by the swell of the dimensions, the nearer we draw towards the most luminous plane, denoting, as it were, a course or tide of stars setting towards a centre. And if figurative expressions may be allowed, it would seem as if the stars thus flocking towards the seat of power were stemmed by the crowd of those already assembled ; and that, while some of them are successful in forcing their predecessors out of their places, others are themselves obliged to take up lateral positions ; while all of them seem eagerly to strive for a place in the central swelling and generating spherical figure.” The actual series is indeed so distinct, that if I would characterise the globular clusters we have resolved, and irrespective of all theory, I would simply attach them to one or other of the systematic series referred to. Their central compressions present a line quite unbroken, and were well illustrated by Herschel, when he compared them to plants in different stages of progress, from juvenescence to proximate ripening or decay. It is not possible that such phenomena can be delusions ; nor are they wholly explained by the mere existence of a "power lodged in the
brightest part.” We have clearly before us, action or progression on the part of this power, distinct and solemn indications, that as on earth, there are also, ruling these high heavens, vast processes of evolution.
On passing to consideration of the more complex nebulæ, vaster fields of change spread out-intimations still more wonderful. It cannot be doubted, that marks of connexion or series, of the distinctest kind are found likewise among the spirals; nay, these latter clusters show not only a gradation, but likewise a continuous scale. Assuming then, that the simple existence of graduated relations renders change or transmutation probable; the question immediately suggests itself, according to which line, or in what direction is transmutation here proceeding? Are the arms of these spirals opening out or closing in ?
On a point so far removed from the domain of definite speculation, nothing can ever throw positive light, save some happy observation—but a fact more pregnant with wondrous truth is not perhaps to be expected from all the researches of future time. If the arms of these astounding objects should be found to be gradually enwrapping their central masses more closely, then may we conceive that ultimate concentration is the destiny of this sparse starry universe. For it is easy to see how, in the course of such change, a spiral might pass through steps of its own form, until it became a globular mass, and that then, pursuing an analogical course, it would advanoe onward through Herschel's range of growing central consolidation, up to that mysterious terminating glory. But, if on the contrary, the branches of any spiral shall be found widening, diverging from encircling arms into lateral spurs, shall we not be constrained to recognise the effective dominion of a dispersing agency, of a power causing the wider distribution or dispersion of the stars? In that case, must we imagine that the globular clusters are dispersing also, so that their course is not from diffusion inwards, but from concentration outwards ? Or, more wonderful still, may the grand material creation be subject to both descriptions of change; manifesting in the midst of its infinite and overwhelming variety, now, a tendency to concentrate, and marvellous dispersions elsewhere? How profound the