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Not long since, the discovery of the centre about which that portion of the universe which constitutes the Milky Way was revolving, was announced to have been made by Maedler, of Dorpat. He (1.) supposes this centre to be somewhere in the Galactic circle, or circle marked out on the heavens by the Milky Way: (2.) That it is in a circle, the pole of which is at the point near à Hercules, toward which the solar system is tending; and (3.) therefore near the intersection of these circles. On examining the stars in the neighbourhood, he is obliged to depart as far from this point as the constellation of the Pleiades, before he can find stars having their proper motions all in one direction, as those near the great centre must have, in consequence of the motion of the sun about it. The writer of this article found that the principal astronomers of Europe, most of whom he saw about a year since, placed very little confidence in this discovery of Maedler, which would seem to be indicated also by the following paragraph of our author :

“ Speculations of this kind have not been wanting in astronomy, and recently an attempt has been made by M. Mädler to assign the local centre in space, round which the sun and stars revolve, which he places in the group of the Pleiades, a situation in itself improbable, lying as it does no less than 26° out of the plane of the galactic circle, out of which plane it is almost inconceivable that any general circulation can take place. In the present defective state of our knowledge respecting the proper motion of the smaller stars, especially in right ascension, (an element for the most part far less exactly ascertainable than the polar distance, or at least which has been hitherto far less accurately ascertained,) we cannot but regard all attempts of the kind as to a certain extent premature, though by no means to be discouraged as forerunners of something more decisive.”—Þ.552, 8 861.

The seventeenth chapter relates to Clusters of Stars and Nebulæ :

“ There are a great number of objects which have been mistaken for comets, and, in fact, have very much the appearance of comets without tails : small round, or oval nebulous specks, which telescopes of moderate power only show as such. Messier has given, in the Connois. des Temps for 1784, a list of the places of 103 objects of this sort; which all those who search for comets ought to be familiar with, to avoid being misled by their similarity of appearance. That they are not, however, comets, their fixity sufficiently proves; and when we come to examine them with instruments of great power, —such as reflectors of eighteen inches, two feet, or more in aperture,--any such idea is completely destroyed. They are then, for the most part, perceived to consist entirely of stars crowded together so as to occupy almost a definite outline, and to run up to a blaze of light in the centre, where their condensation is usually the greatest. Many of them, indeed, are of an exactly round figure, and convey the complete idea of a globular space filled full of stars, insulated in the heavens, and constituting in itself a family or society apart from the rest, and subject only to its own internal laws. It would be a vain task to attempt to count the stars in one of these globular clusters. They are not to be reckoned by hundreds; and on a rough calculation, grounded on the apparent intervals between them at the borders, and the angular diameter of the whole group, it would appear that many clusters of this description must contain, at least, five thousand stars, compacted and wedged together in a round space, whose angular diameter does not exceed eight or ten ininutes; that is to say, in an area not more than a tenth part of that covered by the moon.

" Perhaps it may be thought to savour of the gigantesque to look upon the individuals of such a group as suns like our own, and their mutual distances is equal to those which separate our sun from the nearest fixed star: yet, when we consider that their united lustre affects the eye with a less impression of light than a star of the fourth magnitude, (for the largest of these clusters is barely visible to the naked eye,) the idea we are thus compelled to form of their distance from us may prepare us for almost any estimate of their dimensions. At all events, we can hardly look upon a group thus insulated, thus in seipso totus, teres, atque rotundus, as not forming a system of a peculiar and definite character.”—P. 556, 557, § 865, 866.

“ Double nebulæ occasionally occur--and when such is the case, the constituents most commonly belong to the class of spherical nebulæ, and are in some instances undoubtedly globular clusters. All the varieties of double stars, in fact, as to distance, position, and relative brightness, have their counterparts in double nebulæ ; besides which, the varieties of form and gradation of light in the latter afford room for combinations peculiar to this class of objects. Though the conclusive evidence of observed relative motion be yet wanting, and though from the vast scale on which such systems are constructed, and the probable extreme slowness of the angular motion, it may continue for ages to be so, yet it is impossible, when we cast our eyes upon such subjects, or on the figures which have been given of them, to doubt their physical connexion. The argument drawn from the comparative rarity of the objects in proportion to the whole extent of the heavens, so cogent in the case of the double stars, is infinitely more so in that of the double nebula. Nothing more magnificent can be presented to our consideration than such combinations. Their stupendous scale, the multitude of individuals they involve, the perfect symmetry and regularity which many of them present, the utter disregard of complication in thus heaping together system upon system, and construction upon construction, leave us lost in wonder and admiration at the evidence they afford of infinite power and unfathomable design.”Pp. 567, 568, 0878.

One of the principal achievements of the great reflector of Lord Rosse, is the discovery of what he terms Spiral Systems. The following is an account of one of these :

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“ The 51st nebula of Messier, viewed through an 18 inch reflector, presents the appearance of a large and bright globular nebula, surrounded by a ring at a considerable distance from the globe, very unequal in brightness in its different parts, and subdivided through about two-fifths of its circumference as if into two laminæ, one of which appears as if turned up towards the eye out of the plane of the rest. Near it (at about a radius of the ring distant) is a small bright round nebula. Viewed through the 6 feet reflector of Lord Rosse, the aspect is much altered. The interior, or what appeared the upturned portion of the ring, assumes the aspect of a nebulous coil or convolution tending in a spiral form towards the centre, and a general tendency to a spiroid arrangement of the streaks of nebula connecting the ring and central mass which this power brings into view, becomes apparent, and forms a very striking feature. The outlying nebula is also perceived to be connected by a narrow, curved band of nebulous light with the ring, and the whole, if not clearly resolved into stars, has a resolvable character which evidently indicates its composition.”—Pp. 569, 570, 882.

Another feat of this enormous instrument has been the resolution of the great nebula in Orion, and the consequent overturning of one of the bases upon which rests the celebrated nebular theory of Laplace.

The Fourth Part, which contains but one chapter, relates to the different kinds of time and the calendar. With this the work concludes.

In the Christian Examiner for September is a review of Herschel's Outlines of Astronomy, supposed to be from the pen of a young American astronomer, for whom we anticipate a very brilliant career. It treats the work with great severity, and its strictures, which are numerous, are in the main just, especially those relating to the parts which treat of Cometary orbits and the discovery of the planet Neptune. How far an eminent writer is excusable for inaccuracy in some of the details of his science, to which his attention may not have been particularly drawn, we shall not attempt to decide. One thing is certain, that no eye would be more sure to detect errors in the recently discovered planetary and cometary orbits, than that of the reviewer in question, who, if we are not mistaken in the person, has been most industriously and successfully occupied with these matters during the last two years.

We could ourselves, if disposed to be hypercritical, find many faults. It is easier to do this than to produce an unexceptionable work for popular reading upon such a science.

We have preferred to give such an analysis of the work as should at the same time convey an idea of the present improved state of astronomy. The impression left upon the mind after the contemplation, is one of the vastness of the field which is opened, and the immense amount which still remains to be done in this stupendous science. Every one, however humble his sphere, who contributes anything towards its improvement, confers a possession for eternity, for it becomes incorporated in the great mass of intelligence which has been accumulating and preserving for ages, and which it is impossible to conceive can ever be lost by any of the vicissitudes of human affairs. It is in the hope of exciting a more general taste for astronomical pursuits-pursuits so ennobling and so rich in their immediate rewards to those who engage in them—that the preceding pages have been prepared, and for which the appearance of a work from such a high source, designed for the instruction of the uninitiated, afforded a fitting occasion.

ART. III.-CAMPBELL'S LIFE AND LETTERS.

1. Life and Letters of Thomas Campbell. Edited by WILLIAM BEATTIE, M. D., one

of his Executors. In two vols., 12mo. New-York: Harper & Brothers. 1850. 2. The Poetical Works of Thomas Campbell, complete; with a Memoir, &c. Phila

delphia: Lea & Blanchard. 1845.

THE republication in this country of the “Life and Letters ” of THOMAS CAMPBELL makes this a fitting occasion to take a passing notice of his personal and literary history. Among the heavy taxes imposed on greatness, not the least onerous is that levied by the biographer. No sooner does the child of genius or renown go down to the house appointed for all the living, than this public administrator seizes upon all his memorabilia, and proceeds to appropriate them for the benefit of his heirs at law,—to wit, the great public. The task is generally performed either with a deep veneration for the illustrious dead, or else with a patronizing officiousness, as if the sun had indeed consented to act as usher for the morning star. Very few, however, can afford to have the secrets of their private affairs thrown open to the gaze of an unsympathizing public. There are joys and sorrows that belong exclusively to the domestic and social being, with which the world ought not to intermeddle, and into which it is not often inclined to intrude, unless invited by the excessive communicativeness of ostentatious sorrow.

Biographies of persons recently deceased are generally productions pro tempore,—a further lapse of time is requisite to remove the object a little way from the beholder, that it may be contemplated as a whole as well as in its details. Such temporary memoirs, however, answer a valuable purpose in preserving and making accessible the materials out of which, in due time, the real biographer will construct his work. Much discrimination is required in making such collections of memoirs, for, since they are designed for the public, they should contain nothing that does not properly belong to that distinguished personage. The man who, in the privacy of domestic or social life, should never do or say anything unfit to be made public, might be a very safe man, but he would also be a very reserved, if not indeed an austere one; and any other than such a one could suffer no greater calamity, in his posthumous fame, than to fall into the hands of some admirer, who, with more zeal than judgment, should, à la Boswell, expose to public gaze the picture of his private life.

The “Life and Letters of Thomas Campbell” is a work in some degree obnoxious to these criticisms. Dr. Beattie, the compiler, was the intimate personal friend of the poet during the later years of his life, and an ardent admirer of his genius; was appointed one of the executors in his will, and by consent of surviving friends, became his biographer. Of course, he came to his literary task with much zeal, and has pursued it with an unfailing interest. But while he everywhere manifests the interest that he himself feels, he fails to communicate it to the reader, who is often only a spectator when he should be a participant of the joys or sorrows of the occasion. He seems to have thought that whatever Campbell had said or done, ought to be remembered and admired, and, therefore, that it was his duty to detail everything for public use; and though the example of his admired subject is evidently an unsafe one, yet are his faults and follies all spread out before us, but with so kind a hand as to seem only as the venial aberrations of a gifted spirit, or the exuberancés of genius. This method of writing biography is most pernicious. Either let the faults of the sons of genius be forgotten, or, if they must be remembered, let them be branded with their real character, lest the lustre of mental greatness gild the deformities of vice, and cause crime itself to appear no longer odious.

As a writer, Dr. Beattie is not destined to attain great eminence. He is fitted rather to be the companion of literary men than to assume a high place as one of the craft. He has more taste than genius,—and his taste is rather appreciative than discriminating. Yet has he given us a very readable work,—too large, indeed, by nearly one-half, which is so common a fault among that class of books, that it must be endured as a kind of destiny. But in this case the reader may readily abridge for himself by omitting any portion of the documentary matter with which these volumes abound,—unless, indeed, he fears that he may lose some of the good things that are scattered among these voluminous extracts. The work will unquestionably find readers.

With these notices of the work spoken of above, we take leave of it for the present, designing to devote this paper rather to the subject than to the book,—the life and literary history of Thomas Campbell the poet.

The old Scottish crone was somewhat in error, who, when her little grandchild read to her the story of the patriarch of Uz, at the mention of the three thousand camels, exclaimed, “Och, lassie! the caumels are an auld clan, then,”—for, in fact, the Campbells were among the most recent of all the clans of Scotland, dating back no further than the eleventh century. Among the adventurers who followed the Norman Conqueror into England was Gilespie de

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