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be the case, even in the slightest appreciable degree, this circumstance would furnish data, on which calculations of the greatest importance might be founded.* This consideration induced Sir William Herschel to turn his attention to the double stars, and to subject them to careful and minute measurements; but he had scarcely begun this task, when he was arrested by phenomena of a very unexpected character. Instead of the effect which might be produced by the earth's annual motion, he observed, in many instances, a regular progressive change, "in some cases bearing chiefly on their distance; in others, on their position, and advancing steadily in one direction, so as clearly to indicate either a real motion of the stars themselves, or a general rectilinear motion of the sun and the whole solar system, producing a parallax of a higher order than would arise from the earth's orbitual motion, and which might be called systematic parallax."

*We may perhaps despair of fixing the distance of any but the very nearest of the fixed stars, by means of noting their parallax, i. e. the variation which takes place in their relative position in different parts of the earth's orbit; but there is another and highly ingenious method of determining the distances of the binary stars, which has been pointed out by M. Arago This method depends on the progressive motion of light. If the orbit of a revolving star presents nearly its edge to the observer's eye, it is evident that during one half of its revolution it is constantly receding from the observer, and, during the other half, constantly approaching him. Supposing the light of that star to take thirty days in travelling to the earth from the nearest point of its orbit, it will require more than thirty days to reach the earth from the farthest point. Hence it will appear to spend more time in one part of its orbit than in the other; and the difference between the calculated and the apparent time of its transit through the nearest and farthest halves of its orbit, though it should be but a few seconds, will supply the astronomer with the data he requires. The two observed semi-revolutions differ from each other by the double of the time which the light takes to pass across the star's orbit. Hence half the difference of time expressed in seconds, and multiplied by 200,000, the number of miles which light traverses in a second, will give the diameter of the orbit. This element known, the distance from the earth is easily found. What a new accession to our knowledge will be acquired, when, by a long and careful observance of these double stars, this discovery is made. "The day in which the distance of a double star is determined," says M. Arago, "will be the day in which it may be weighed, in which we shall know how many millions of times it contains more matter than our globe. We shall thus penetrate into its internal constitution, though it may be removed from us more than 120,000,000,000,000 of leagues."

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After a patient investigation of twenty-five years, the elder Herschel ascertained, what has been further established by subsequent observations, “that there exist siderial systems, composed of two stars, revolving about each other in regular orbits.” Between fifty and sixty instances of changes in the position of double stars, were adduced by this astronomer, in communications published in the Transactions of the Royal Society for 1803 and 1804. The revolutions of these combinations of stars round each other, are of extremely different periods, one in the Crown being completed in little more than forty years, while that which is found in the Lion, extends to a cycle of no less than 1200 years. Many of the double stars exhibit the curious and beautiful phenomenon of contrasted or complimentary colours. In such instances, the larger star is usually of a ruddy or orange hue, while the smaller one appears blue or green. The complimentary colour of the smaller star may, in some instances, be considered as an optical illusion; but the contrast cannot be thus accounted for in others. The double star in Cassiopeia, for instance, exhibits the beautiful combination of a large white star, and a small one of a rich ruddy purple. Sir John Herschel, in mentioning these combinations, indulges his fancy in the following somewhat amusing remarks:-" It may be easier suggested in words, than conceived in imagination, what variety of illumination two suns,-a red and a green, or a yellow and a blue one,-must afford a planet circulating about either; and what charming contrasts and 'grateful vicissitudes,' -a red and a green day, for instance, alternating with a white one, and with darkness,-might arise from the presence or absence of one or other, or both, above the horizon."+

Without entering into this speculation, which, of course, is taken from the views and tastes of human be

* In some instances the combination consists of three stars, in others of four, and even of more, with very complex motions.

↑ Herschel's Astronomy, p. 395.

ings, and may or may not bear reference to the feelings of the animated creation in these distant worlds, I cannot dismiss this curious subject without a single remark

the beautiful variety which appears in the works of the Creator, combined with a sameness which gives evidence of the architecture of One creating hand. The revolving motions of these binary stars have been found to be governed by the same centripetal and centrifugal forces as regulate and preserve the order and harmony of our own planetary system. M. Savary, Professor Encke, and the younger Herschel, having each applied the Newtonian law of gravitation to the calculation of the elliptic orbits of binary stars, have thus elicited their periods, and the forms of their ellipses: and the correspondence between their calculated and observed places, has satisfactorily proved the existence of the law in these remote regions of the universe. Here, then, a new element is added to our knowledge of creation. The identity of the light emitted by the fixed stars, and by our own sun, had been previously ascertained, as well as various other particulars which seemed to mark these distant luminaries as belonging to the same universal system; but although, united with these considerations, the phenomena of comets seemed to intimate some connexion between the great laws which govern our own planetary worlds, and those of other suns, and although analogy certainly rendered the extension of these laws to all things created more than probable, it was not till the revolution of these binary stars was observed, and subjected to calculation, that the fact was demonstrated.

It is most curious and instructive to trace the same character in the operations of the Eternal, throughout every corner of His universe, which science unfolds to our view. It is true, that even now, after all the insight which astronomy has afforded of more distant worlds, it is but a faint glimpse that we obtain; but still that glimpse, while it opens up a profusion of wonders, establishes principles which connect system with system, and

group with group; and the gradation and variety which it displays, correspond so remarkably with what we perAceive around us, both on the large and the minute scale, rothat we seem warranted in feeling confidence in our reasonings founded on these analogies, and while we trace every where the exercise of the same power and wisdom, may legitimately infer also, every where, the exercise of the same moral qualities.

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THE inconceivable space, and innumerable quantities, with which we become conversant in contemplating the phenomena of the heavens, while they stretch the human mind, till it is lost in infinity, are calculated to produce a peculiar effect on our religious views and feelings. They elevate our conceptions of the Creator, and fill us with the utmost astonishment and awe. But there is something so incomprehensible in the attributes of that Self-existent Being, by whose power these wonders were created, and by whose wisdom they are governed, as to overpower and confound the mind. In the presence of such a God, we appear to become as nothing; and, were we, only to dwell on the immensities of nature, it seems as if we should scarcely be in a fit state for receiving the truths of Revealed Religion, or for cherishing those pious and filial affections, which the doctrines of the Gospel are so admirably adapted to excite. After wandering through the boundless realms of space, and observing worlds on worlds, and systems on systems, and even groups of systems on groups, in interminable succession, all glorious with the perfections of the Eternal, it is not easy to conceive, that the dreadful and stupendous Power, who created and sustains this infinite universe, should condescend to care for such worms of earth as we are,—much less that He should extend to us the tender affections of a Father. To think of such a Being as providing food for the ravens, and sustaining the sparrow in its flight, or even looking regardfully on man, and numbering the hairs of the hoary head, or counting the beatings of the infant's heart, seems, to the mind thus exclusively prepossessed, as little better than a fond and idle dream. A general Providence, such a mind will readily admit; but,

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