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ASTRONOMY, now the most perfect of all the sciences, is also the most sublime and ancient. It separates man in thought from the spot upon which his foot is planted; makes him acquainted with forms and spaces, in comparison with which terrestrial magnitude and distance shrink into insignificance; and unfolds the constitution of the universe, as a scheme involving the intimate connection of the mighty and remote masses that are open to observation, their incessant activity, unfailing order, and mutual dependence. The idea of extension-a feature of the sublime -is created by the scenes with which we are in immediate contiguity, and enlarged by the knowledge we possess of the superficies of the globe; but it is wonderfully expanded by the science which deals with the objects that are exterior to its surface. By measuring the distances and volume, and weighing the masses, of the planets-by calculating the orbits of the comets, which accomplish their aphelia in the regions of invisibility, and only discover themselves to us during a scanty portion of their course-by contemplating the stellar firmament, which, in the case of its nearest members, has required the highest modern intelligence, aided by the finest instruments, to detect even the slightest amount of parallaxby such investigations as these, we gather some faint conception, improving to our nature, yet humbling to our faculties, of the immensity in which the Creator centres, with whom the vast scheme originated, and to whom alone it is reserved to estimate

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its length and breadth, its depth and height. Man has learnt to distrust and disbelieve the evidence of the most perfect of his senses. He has been taught that the apparently quiescent earth is in perpetual movement; that the real motions of the celestial bodies are, in most cases, in direct antagonism to those which he daily perceives; and that his own world, instead of being the "greatest in the kingdom of heaven," having subordinates under it in the sun, moon, and stars-the long and fondly cherished dream of antiquity— is, in reality, one of the smallest provinces in the great empire of Nature.

Astronomical inquiry goes back to a remote era, and had its origin in the East. The splendour of the celestial phenomena; the fact of periodical changes and of accompanying powerful effects being produced upon the surface of the earth-such as alterations in the temperature of the air, the processes of vegetation, and the habits of animals, these are circumstances too obvious and striking to have escaped attention, or not to have awakened curiosity. Accordingly, it is only reasonable to consider their thoughtful observation as coeval with the primitive age of man. We may undoubtedly regard the great levels of South-western Asia-the country between the Nile and the Euphrates-the cradle of mankind as the birth-place of the science, and the scene of its first culture. Though no original memorials have been preserved of the facts noted, nor of the progress made by the earliest inhabitants of that region, yet the references made by subsequent historians showing their devotion to the study of the heavens, and the reputation assigned to them for such pursuits by the unanimous voice of antiquity, long after the downfal of the Chaldean monarchy, may be accepted as sufficient proof of an inquisitive eye having been cast from that quarter upon the objects and movements of the firmament. The district possesses many natural advantages for observation; a climate not subject to sudden variations, a serene sky, an open horizon, and a remarkably transparent atmosphere. Upon a winter night in our northern latitude, the spectacle is brilliant that is unfolded over the head of the traveller by the unclouded heavens, as he emerges from the smoke of the city into the clearer air of the country; but the mild beauty of the moon, the vivid sparkling of the stars, and the intense darkness of unoccupied space, present a far more glorious exhibition, as seen through the purer medium of an eastern clime; and nothing more forcibly arrests the attention of the European than the magnificent canopy which the eventide unveils to him, on first visiting the oriental deserts. Besides the striking garniture of the sky, the occupations of man in the more primitive times-the warfare of the huntsman by night and by day-the custody of flocks and herds, wandering in solitary places, and requiring the shepherd's vigilance to protect them from the beasts of prey,-together with the influence of the revolving seasons, coincident with celestial changes, upon the flowers of the field, the trees of the forest, and the productions of the vineyard-would combine to stimulate interrogation respecting the vault of heaven, the meaning of its visual glories, and the laws of their movement.

From the book of Job-in all probability the record of some pastoral chief migrating at an early period on the plains near the Euphrates-we gather indications of the heavenly bodies having attracted the watchful observance of mankind. Though it may be doubtful whether our version rightly renders the asterisms named by Arcturus, Orion, and the Pleiades, it is obvious, from the tenor of the passages in which they are introduced, that principal constellations or single stars are intended. The temple of Belus at Babylon, coeval with the foundation of the city, whose ruins are identified with those now extant of Birs Nimrood, is supposed to have been devoted to an astronomical as well as an idolatrous purpose. Its reported construction would seem to intimate this, being of a pyramidal form, with its four faces opposed to the four cardinal points of the horizon. Upon the summit, according to the Greek historian, the Chaldean priests contemplated and exactly noted the risings and settings of the stars.

At the time of the capture of the city by Alexander, his tutor, the philosopher Aristotle, is said by one of his commentators to have received from Callisthenes a catalogue of eclipses observed there during a previous period of 1903 years. Though there may be considerable exaggeration here, yet there is, no doubt, substantial truth in the statement, since Ptolemy gives six Chaldean eclipses, which seem to have been taken from the catalogue, the earliest of which, however, goes no farther back than the year 720 B. C., answering to about the time of the first captivity of the Jews. A comparison of these ancient with modern observations led Halley to the discovery of the doctrine of the moon's acceleration—that is, that she now moves round the earth with greater velocity than formerly, the cause of which Laplace has satisfactorily explained. Ptolemy distinctly refers to Chaldea as furnishing the best and most numerous astronomical observations; and Cleomedes, speaking of a peculiar eclipse of the moon, states that "no astronomer, whether Chaldean or Egyptian, has ever recorded one of this kind." It is remarkably illustrative of the habit of diligent observation, that the Chaldeans were acquainted with the cycle of 6585 days, during which the moon makes about 223 synodical revolutions, and experiences the same number of eclipses, alike too in order and magnitude, comparing cycle with cycle. To them is attributed the invention of the zodiac and the duodecimal division of the day.

Superstition was the mainspring of that observance of celestial phenomena which prevailed at an early period in the regions bordering on the Euphrates. The heavenly bodies were the objects of religious veneration. We can easily understand how, as the light of the primitive revelation respecting the Supreme Ruler faded from the mind, men fell into the error of regarding the glorious realities of the firmament as the governing intelligences of the world. Their uses in the economy of the universe; their resplendence and incomprehensible character, to the untutored observer; their elevation and far removal from man; their regular disappearance and return; their stability and undiminished lustre ;these are circumstances upon which popular ignorance would be likely to fasten, convert into intimations of intelligent existence, and establish thereby the worship of the stellar orbs. Such, in subsequent ages, has been the effect of the impressive appeal, made by the great lights of heaven to the physical eye, in the absence of information. Even in our day many a savage falls prostrate before the rising sun, or honours with religious ceremony the different phases of the moon.

The supposed possibility of divining future events by the appearance of the heavens, was another inducement by which the ancient mind was powerfully actuated to observe the face of the sky-a hollow but imposing superstition, springing out of the witnessed regularity of the effects produced upon the face of nature by the heavenly bodies. The apparent varying altitude of the sun, at different times of the year, affecting the earth with different degrees of heat as his rays are more or less oblique, producing thereby the phenomena of the seasons, was one of the physical facts open to the notice of the early observers. They saw not only the day and night of the world, but the summer and winter of the world's year, through which vegetation quickens, flourishes, and dies, determined by the movements of a mighty luminary in the firmament; and the supposition was not unnatural, in a connection so close and marvellous, that the sun was an intelligent body appearing in certain positions to prognosticate certain events. The office supposed to be performed by one of the heavenly bodies was also assigned to the rest, and the connection observed between them with the changes upon the surface of the earth was likewise extended to every class of circumstances, even the physical and moral qualities of men; and thus, in the observation of effects regularly occurring, their true causes overlooked, but being plainly dependent upon celestial appearances, the art of judicial astrology had its origin. The Chaldean priests marked the position of the stars in their courses, and of the moon

walking in her beauty, for astrological purposes; and hence inspired prophecy, when denouncing the divine judgments against Babylon, challenges the "astrologers, the stargazers, and the monthly prognosticators," to try their power to avert them. The predominance of this delusion during the middle ages in Europe, transported hither from the East, is well known. The fate of empires, the destiny of monarchs, the consequences of battle, the private fortunes of individuals might, it was supposed, be gathered from the position of the stars at the time of the nativity of the persons on whose behalf they were consulted, compared with their position at the time of the consultation; and without applying to the seer, who was imagined to read in the heavens the character of every event, whether it would prove favourable or adverse, scarcely any public measure or private enterprise was undertaken.

The honour of priority in observing the celestial sphere has, however, been claimed for the ancient Hindús, the Chinese, and the Egyptians; and to the two former especially, a cultivated knowledge of its mechanism at a far distant era has been assigned. It would involve a tedious and unsatisfactory detail to consider this question at length. It may suffice to remark, that the preponderance of evidence is in favour of the plains of Chaldea being the primal seat of application to observative astronomy-that from thence, as from a general centre, it radiated, at some unknown but remote period, towards the banks of the Nile on the one side, and to India and China on the other-and that, in the infancy of national existence in those countries, the rising and setting of the stars, lunar and solar eclipses, and conjunctions of the planets, were objects of attention, with an entire reference either to astrology, religion, or policy of state. The Hindú tables claim an epoch of 3102 years before Christ, and fix a general conjunction of the sun, moon, and planets, at that era, the beginning of the Caliyug, or iron age of their mythology; but modern calculation proves the impossibility of such a conjunction then occurring-that Venus, in particular, could not have been near it at the time specified. The tables therefore are not established on observation, but have been calculated backwards, either from data supplied by native application in a comparatively recent age, or derived from the Greeks and Arabs. In opposition to this last conjecture, the proud scorn of foreign nations entertained by the Brahmins has been quoted, which seems to have been special in relation to the Greeks or Yavans, from their proverb that no base creature can be lower than a Yavan; but the following curious passage from one of their earliest astronomers upholds the former opinion :— "The Yavans," says he, "are barbarians, but this science is well established among them, and they are revered like holy sages." With reference to the ancient Chinese, we have little in their annals beyond records of solar eclipses, which were regarded as prognostics of importance to the empire. Those which may be depended upon, as having been actually observed, commence with the year 776 before Christ, and terminate with the year 1433 of our era. But nothing is more dubious than the credit of their native histories; and nothing more certain than the ignorance of the professedly scientific class, even of the simplest operations of practical astronomy, when intercourse was first opened with the people of the West. In Egypt, no doubt, attention to celestial phenomena commenced with the era of its early inhabitants. The exactness with which some of the pyramids have been made to face the four cardinal points has engendered the suspicion that they were designed for an astronomical use; and authorities may be cited, who state, that they terminated at the top in a platform which the priests occupied as an observatory of the heavens. But if the Greek philosopher taught them how to find the height of the pyramids by the shadow, one of the most simple examples of practical geometry, we can form no high idea of the accomplishments of the Egyptians. In fact, Ptolemy, who lived in the country, and may be presumed to have been acquainted with its records, derived none of his materials from that source, but only quotes the observations of the Chaldeans.

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