raing and tossing up their caps for sheer ecstasy. They were soon distributed in knots all over the field, each party intent upon its own amusement. Here was a troop of miniature grenadiers aping the fierce looks and warlike gestures of the military quartered in the neighbouring town:-There a pack of harriers ready to start at a moment's warning, in pursuit of the hare who was to have fifty paces grace. In one direction an assembly of those about to emerge from the reign of pinaforism were chalking out a ring for marbles:-In another, a party of embryo naturalists were rambling along the banks of the stream, in search of bees and butterflies; while here and there a tiny idler met the eye, stretched in careless indolence upon the grass, turning up face to the sun

'To drink the spirit of the golden day.'

its

It was a festive hour to me. If the rich garniture of naturé needed aught to heighten and add zest to its charms, it was to be found in the gushing spirit of unreined and innocent excitement before me.

"It were a thankless task to become a prophet of evil, when all around is rife with beauty and joy. Yet, childhood! they err who think that thine are halcyon days-days of uninterrupted calm and unmingled bliss. It is a strange and sad truth, that while the creature of instinct lives out its little hour, in fulfilment of its Maker's fathomless designs, man, the child of reason and religion, even in the spring of his being, has his spirit disquieted by his lawless passions; and, with the ray of light vouchsafed to guide and gladden him on his way to the grave, arise a thousand real or imagined ills to dim the light and dissipate the joy.

"I thought not of this then however: but as I looked upon the glowing sky, and upon the young groups beneath it, breathing nothing but gaiety and animation, I forgot how soon that sky might be clouded by storms, and those glad young spirits broken by disappointment,

"And that spectacle recalled,-it would have been wonderful had it not recalled to my recollection the spring-tide of my own enjoyments,—when a keen relish for gratification braced every fibre, and rushed through every vein. I sometimes gaze upon the scenes amid which the days of my childhood were spent. The azure of the heavens is as pure and unmingled ;-the sun's

pomp of light is as glowing and resplendent: Nature paints with as lavish a hand the blushing rose, and pours as rich a perfume on the violet: Spring decks the earth with as living a green, and winter fringes the leafless boughs with as delicate a white. Yet amid all their beauties I find, with the Arabian proberb, that 'the remembrance of youth is a sigh.' 'T was my own luxury of spirits which gave the gorgeous scenery an added charm; and sky and sun, and fields and flowers, and spring and winter, have never since appeared so beautiful as then.

"All this and more recurred to me on that afternoon; and the retrospective visions of my childhood, glittering with the light of incipient being, acquired again a substance and a reality, as I saw them embodied in the fairy forms of youth and hope, flitting about in the sunlight.

“I cherished, too, the fond and fervent anticipation that, when care should come to ruffle the calm current of their delights, the promises of religion might be at hand to soothe and console them; or that, if they should be fore-doomed to fall early by the hand of the spoiler, their young and unshackled spirits might be found soaring and singing before the throne of the Eternal."

I enclose the foregoing effusion of my worthy relative's pen as the second of my course of sketches. Youth, Manhood, and Old Age will complete the series.

NEANIAS.

WHAT ARE COMETS? No. 2.*

IT was not till about the close of the 17th century, that the motions of comets began to engage the attention of astronomers; previously to that time they had been generally considered only as a larger kind of meteors, passing in straight lines through the lower regions of the heavens, and gradually dissolving into atmospheric vapors. The success with which the principles of Copernicus, Galileo, and Kepler, had been applied in explaining the motions of the earth, and other planets, gave throughout all Europe an extraordinary stimulus to these studies; and when

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astronomers had found, by their observations, that comets move through the same regions of space as the planets, they soon conceived the idea of determining their paths by the same laws of motion to which the other bodies are subject, and which, as the philosophical novelty of the day, they were eager to bring forward on all occasions. Hevelius was the first who discovered that the paths of comets are curved to the sun; but the worthy burgomaster's preconceived notions, with respect to the unsubstantial nature of those bodies, were so inveterately fixed in his mind, that they could not be removed even by the striking observations which he had the opportunity of making on the great comet of 1680.1 The passage of this brilliant phenomenon, descending nearly in a straight line to the sun, and rising again from him in a similar direction, inspired most of the astronomers of that age with more exalted ideas of those mysterious bodies; and, as if to atone for the contemptuous opinions previously entertained respecting them, they went to the opposite extreme, and elevated them at once from the degraded rank of transient exhalations, to the dignity of planets, permanently revolving in fixed orbits. This opinion was immediately given to the world by Jame Bernouilli, who, in the following year, 1681, published in German, at Basle, his "New Introduction, showing how the motions of the comets may be reduced to some certain and geometrical rules, so that their appearance may be predicted."

Sir Isaac Newton, in 1687, published his Principia, in the third book of which the theory of comets occupies a considerable space, and the periodic return of those bodies is shewn to agree with the laws of gravitation, counteracted by an adequate projectile force.2

1 His remarks on the comet of 1683 are curious, and the following extract from them will shew how he received the new doctrine of the periodic revolution of comets, when it was first promulgated. "Sept. 2do. Hac die iterum diametrum cometæ capitis micrometro diligenter dimensus sum9' 7"-die 16° Aug. eodem micrometro obtenta tantummodo 6′ 5′′, sic ut notabiliter spatio 17 dierum creverit. Non nemo diceret, id factum esse, quòd in ultima observatione vicinior multò fuerit terræ; atque ideo clarius et lucidius caput exhibere debebat, præsertim si corpus esset æternum (ut quidum statuunt) quod rursus certo tempore, absoluto suo circulo, nabis in conspectum redit. Sed a contrario, caput longé obtusius rariusqus ultimó extitit, sic ut distinctissimé notari potuerimus materiam capitis sensim se dissolvisse ; id quod autem multó melius cum nostra convenit hypothesi:" Phil. Trans. abridged to 1700, vol. 1, p. 448.

2 Newton however no where proves that comets are revolving in fixed orbits. The utmost point which his demonstration can be said to reach, is in the 40th prop. of his 3rd book, viz. "cometas in sectionibus conicis, umbilicos in centro solis habentibus, moveri, et radiis ad solem ductis, areas temporibus proportionales describere." This of course refers only to that portion of their paths which is visible

The subject was at the same time taken up by Dr. Halley, whose researches were carried far beyond those of his predecessors, for he first conceived the idea of trying the question by the test of fact; and on this principle he proceeded not only to point out the intervals at which some comets had re-appeared, but also to predict the periods at which they would again return. One of these was the comet of 1682, which he considered to be the same that had been observed by Apian 1531, and by Kepler and Longomontanus in 1607, and which he therefore expected to be again visible to us in 1759. The appearance of a comet that year seemed to verify these calculations, and dispelled every doubt that had been entertained as to the truth of the doctrinc. From that period it has been looked upon as fully established, and the efforts of some of the most distinguished among later astronomers, have been applied in order to explain and perfect the principles on which it is founded. The Abbé Boscovich and Dr. Maskelyne, La place in his Mécanique Celeste, and Legendre in his Nouvelles methodes pour la determination des orbites des Cométes, have not only sanctioned it by the authority of their experience, but have also powerfully supported it by the most ingenious combinations and skilful deductions of profound mathematical science. To enumerate all the advocates of this theory would be to recite the names of nearly all the most eminent among the astronomers and mathematicians who adorned and enlightened the past century. The laborious Euler, and indefatigable Lambert, and the French Academicians, Clairault, and De la Grange, illustrated the subject by various papers in the transactions of the learned bodies of which they were members. M. Pingré in his Cométographie published a systematic arrangement of its intricate principles, and M. Méchain adopted them in framing his calculations of the orbits of the comets of 1774 and 1790, as given in the Connaissance des temps for those years.

to us, and proves only that their line of motion is curved by the sun's attraction. Beyond this, all that Newton advances on the subject is mere conjecture. "Fallor ni genus planetarum sint, et motu perpetuo in orbem redeant," (Lemma iv, book 3) are the strongest terms in which his opinion is stated, and he proposes some modes of calculating, by which he conceives that the question may be decided; but they end with no Q. E. D. On the contrary, he says (prop 41.) Orbium vero transversas diametros, et revolutionum tempora periodica, ex collatione cometarum in üsdem orbibus post longa temporum intervalla redeuntium, determinanda reliquo.

Sir Henry Englefield followed with much ability in the same path, and it is greatly to be regretted, that he did not complete the history of the principal comets, "particularly with regard to their nuclei and tails," which he intended to be a second part of his work. Such a review of the facts which afford the ground of a theory, ought to precede, as it is of more importance than the calculations by which it may be explained, but cannot be proved. Of late, Mr. Ivory has prosecuted the same enquiry,Dr. Olbers has been engaged in adapting the science of numbers to the same object,—M. Damoiseau has fixed the next perihelion passage of the comet of 1759, for the 16th November, 1835,M. De Pontecoulant for the 2nd of the same month,-and Mr. J. W. Lubbock has endeavoured to place this still obscure subject in a clearer and more satisfactory light. Against this array of formidable authorities, I have nothing to oppose, but plain, simple, and incontrovertible facts.

To investigate such calculations with the hope of detecting any material errors, would be a fruitless undertaking; and to those who may feel interested in the enquiry, the methods prescribed for determining the orbits of comets must undoubtedly be so familiar, that it is unnecessary to state the different formula that have been used in solving the problem. There are, however, two points on which the question appears mainly to hinge, and to which therefore I particularly wish their attention to be directed; the first is, that the only data on which this theory is founded, are derived from observations made on that very limited portion of a comet's path which is visible to us; that from three such observations made at different periods, are computed the velocity and direction of its motion; and that from these are deduced the elements of its invisible progress.

The second point is, that in the space of 150 years since this opinion was first put forth, the actual operations of nature have furnished but one solitary fact, by which it appears to be supported; and that even this fact affords no positive proof of the truth of the theory, for it does not follow of necessity from the nearly equal spaces between the years 1531, 1607, 1682, and 1759, that it was the same comet which appeared at each of those periods. The bodies discovered by Encke and Biela have returned several times, and are regarded as confirmatory of this opinion. But their narrow orbits of 3 and 63 years, bear no