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highly satisfactory reasoning I cannot enter, but must refer the reader to the work itself: and I am quite sure that no candid mind can resist the conclusion to which he comes that, whatever may be the scientific merits of this hypothe sis, they cannot, in sound reason, affect at all the view of the universe as the work of a wise and great Creator. 'Let it be supposed,' observes he, in conclusion, that the point to which this hypothesis leads us, is the ultimate point of physical science; that the farthest glimpse we can obtain of the material universe by our natural faculties, shows it to be occupied by a boundless abyss of luminous matter; still, we ask, how space came to be thus occupied,-how matter came to be thus luminous? If we establish, by physical proofs, that the first act which can be traced in the history of the world is, that "there was light," we shall still be led, even by our natural reason, to suppose that, before this could occur, "God said, let there be light.” '

Dr. Nichol, who adopts the hypothesis of Laplace, as to the gradual conversion of nebulæ into stellar and planetary systems, and illustrates it in a very striking manner, deduces from it the following pleasing and sublime views :—' The ideas I have presented to you-august and strange though they are should not appear in contradistinction to what every moment is passing around us. Supposing these phenomena did unfold the long growth of worlds, where is the intrinsic difference between that growth and the progress of the humblest leaf, from its seed to its intricate and most beautiful organization? The thought that one grand and single law of attraction, operating upon diffused matter, may have produced all those stars which gild the heavens, and, in fact, that the spangling material universe is, as we see it, nothing other than one phase of a mighty progress, is indeed truly surprising; but I appeal to you again, in what essential t were different from the growth of the evanescent plant? T'here, too, rude matter puts on new forms, in outward shape most beauteous and in mechanism most admirable; and there cannot be a more astonishing process, or a mightier pow

er, even in the growth of a world! The thing which be wilders us is not any intrinsic difficulty or disparity, but a consideration springing from our own fleeting condition. We are not rendered incredulous by the nature, but overwhelmed by the magnitude, of the works;-our minds will not stretch out to embrace the periods of this stupendous change. But time, as we conceive it, has nothing to do with the question, we are speaking of the operations, and tracing the footsteps, of One who is above all time,—we are speaking of the energies of that Almighty Mind, with regard to whose infinite capacity a day is as a thousand years, and the lifetime of the entire human race but as the moment which dies with the tick of the clock that marks it—which is heard and passes."

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FIFTH WEEK-SATURDAY.

stars.

XII. THE STARRY HEAVENS.-BINARY STARS.

THERE is yet another singular phenomenon in the starry heavens, which shall form the subject of this day's paper,-I allude to the curious fact of the existence of binary revolving These are very numerous. Sir William Herschel has enumerated upwards of 500, and Professor Struve, of Dorpat, has recently added to this number between 2000 and 3000. When these combinations were first observed, it was thought probable that their extreme apparent proximity would enable astronomers to ascertain their distance from the earth, by the discovery of an annual parallax; for supposing, as might naturally be expected, that one of the combined stars should be nearer the earth than the other, and that both should prove to be stationary in relation to each other, the motion of the earth in her orbit would cause these stars to alter their apparent position; and, if that should be the case, even in the slightest appreciable degree, this circumstance

* Architecture of the Heavens, pp. 143, 144.

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

* 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 here 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 reeeding 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.'

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.'

After a patient investigation of twenty-five years, the elder Herschel ascertained, what has been further established by subsequent observations, that there exist sidereal systems, composed of two stars, revolving about each other in regular 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.'t

* 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.

Without entering into this speculation, which, of course, is taken from the views and tastes of human beings, 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 on 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 unfolds a profusion of wonders, establishes principles which connect sys

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