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the distance that separates Neptune from our sun. The period of revolution is 520 years, being three times as great as the period of Neptune. "Now we know that a planet placed at the same distance as that which separates the components of Alpha Cygni would occupy a much less period than 520 years in completing a revolution: in fact, its period would be about 300 years." Hence it follows that the attractive powers, and consequently the sums of the masses of these two components of A. Cygni, are less than the sun's mass; and taken together, their united weight would not amount to more than one third of this sun's. A similar conclusion is arrived at in the case of the star Alpha Centauri, to the components of which Mr. Hind assigns a revolution of eighty-one years, and a distance from each other exceeding the earth's distance from the sun about fifteen times; a planet similarly placed would not occupy more than sixty years in completing the same revolution: therefore the united mass. of the components of this star, also, must be for the same reason considerably less than that of our sun; although some difference is implied in the condition of that star as regards the intensity of its light, which is far greater (as we have already shown) than that given out by our sun.

This latter circumstance, we may observe in passing, shows us that the brightness of a star is not always dependent upon its magnitude or mass. But the conclusion derivable from this mode of weighing the stars and determining their mass, reveals to us what by other means it would be impossible to discover, the vast size and ponderous nature of the smallest of them; and thus without the possibility of even a glimpse at the real

diameter of a single star in the heavens, which would from their vast distance and intensity of light ever be an insurmountable difficulty, the ingenuity of man has enabled him (without any great stretch of imagination, and following the pattern of our own sun) from the deductions of science, to arrive at a near approximation to what it really is, or what is the actual size and bulk of many a grand centre, round which roll (as in our own case) hundreds of planetary worlds (many of which are probably inhabited like our own), fed by their light, and controlled by the same Marvellous Power which pervades creation, and a knowledge of which has thus revealed to us what otherwise would be really hidden from our gaze for ever, their fitness to be the centres (which they are) of systems innumerable; and here what the telescope may have left undone, the spectroscope has completed, when it points to every star in the heavens, and says, as plainly as though an angel himself had told 66 us, There shine millions of other suns, but composed of the very same materials and constituents, which are to be found in each shining orb, as exist in your own sun, in your own earth.

Not only therefore is it true there is nothing new "UNDER the sun," but there is nothing new "IN the sun." One is but the repetition of the other: the only difference being "difference of glory," as described by St. Paul; difference of magnitude and mass and colour; difference of intensity of light; difference in the extent of gravitating power, by which the inhabited planetary worlds, that roll by millions round their thousand million suns, are swayed; difference likewise in the number of those satellite worlds; and difference in their asso

ciation with other companion suns, given possibly to aid them in providing additional and successive floods of light and glory over the worlds they control; but alike as being the grand representatives of the life and light that exists and spreads through the most distant regions of infinity. These are however evidently not the fires of merely etherial lights, without substance or mass, or use, but to shine; but ponderous material masses of glory, whose heat warms, whose light cheers, and whose weight controls and regulates and keeps in their several places alike the comparatively small system to which we belong, and the gigantic system where Sirius shines resplendent with a power of twelve million times the light and power of our sun; and holds in his grasp, doubtless, a proportionate number of worlds obedient to his sway.

Thus the proper motion of the stars enables us to form a conception of their mass and magnitude, notwithstanding their vast distance; and in displaying it, assigns no limit to either, any more than the magnitude of a single stone of a building would enable us to conclude the dimensions of the entire palace to which it belonged, or of other and grander stones in the building.

CHAPTER V.

THE PLANETS.

E now approach the contemplation of a different class of bodies from those we have had chiefly

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under our consideration. Hitherto we have been wandering among the great centres of solar systems, suns, or stars, and their combinations. We now direct our attention to the planetary worlds (for so we may term them) that revolve around their centres. The word world properly implies a habitation, such as our own world exhibits; and could not be applicable correctly to vast globes of fire, or incandescent metal. To these worlds we have already referred briefly, but only incidentally and indirectly,—assuming their existence for the purpose of explaining the place occupied by their primaries, or suns, in creation, as centres and sources of life and light and heat.

We now approach a different class of bodies, which claim a certain amount of sympathy from us, as being fellow worlds placed in analogous circumstances with our own; and doubtless some of them, at all events if we knew but all, claiming a deeper sympathy not only of matter but mind; and resembling the earth not only in being members of the same solar family of worlds,

but containing on the surface, if not precisely human beings, yet material creatures designed to inhabit them, possessing life and intelligence, and the power to derive enjoyment from both, in as great a degree, if not in a greater, than is realized in the habitation which is our home. Round our sun revolve eight such globes, of a magnitude sufficient to warrant a close and searching examination of them, and comparison with our world.

Besides these there are above 100 smaller bodies, most of them discovered within the last twenty years, to which the name Asteroids has been given, and the comparatively diminutive size of which, combined with their distance, renders an examination of them fruitless as to their planetary masses. Some of the planets exhibit miniature systems themselves, as in Jupiter and Saturn, having solid planetary bodies moving round them as their centre, as the moon does round us, and probably fulfilling the same conditions. Of these planetary satellites we know seventeen for certain, to which our own moon may be added. We have here a class of bodies that separate themselves entirely from any that we have been hitherto contemplating, and perform a different part in the universe. They are, in fact, the receptacles of life as well as light, not the givers: and their very place in the heavens, and their every movement therein, their material envelopes, - all, when examined, convey to the mind the irresistible impression that they are, or are intended to be, dwelling-places-habitations-where life and probably intelligence would be found were it possible for us to visit them. This invests the examination of these bodies with peculiar and undying interest;

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