CHAPTER VI. RELATION OF THE FORM AND THE INTERNAL ACTIVITIES OF GALAXIES.—PROBABLE CHANGES OF THESE FORMS.—CONJECTURES RESPECTING THE PROGRESS OF THE MATERIAL UNIVERSE. T follows from those relations with the Infinite, IT which, though partial and dim, are yet the pride and strength of the human reason, that the desire of knowledge is never quenched by attainment, nor-however signal the triumph—the task of inquiry ever ended. That brilliant train of discovery, along which I trust in my reader's company-I have essayed to travel, might indeed have amply satiated any finite mind; and, as to man, it penetrates alike through time and space, immeasurably beyond the limits which contain the terrestrial concerns or even the duration of his race: nevertheless, no sooner have we apprehended its scope, and been aroused from our astonishment at its stupendous reach, than ambition is fired afresh, and speculation, never at rest, takes wing towards remoter regions. I. Although the facts established in the last two chapters are drawn from observation on a limited number of stars, I think they entitle us to conclude generally that every galaxy is a grand dynamical system, in which the separate orbs are united according to the principle of gravitation — manifesting that union through their motions. These magnificent clusters indeed-whether of the simple form of that in HERCULES, or complex as the Spirals are, like the great oak-tree, superb organizations, where every atom has its essential function and place, and the highest-the ultimate problem regarding them is, in what manner do the various atoms conspire in each case to produce the whole as we see it; with our knowledge of that internal organization, can we now construct or explain the Nebula? In the earlier part of this Essay, I described with some minuteness the more prominent forms of these extraordinary objects; and postponing for the time all thought concerning their interior relations, I attempted to descry whether there were any general laws whose action upon such masses might explain their leading shapes. Traces of such laws appeared. The forms of one large class of them-viz., the globular, intimated, in |