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from barbarism, but have not yet reached the confines of civilization.
Nothing is more essential in transacting the common affairs of life, or conducive to the well-being of society, than an easy and accurate measure of time; but as our ideas of duration include those of motion, it is necessary that this motion should be constant and uniform, in order that its subdivisions may possess the requisite accuracy. The globe we inhabit, however, does not afford any motion adequate to this purpose; and it is among the heavenly bodies alone that such an invariable standard can be found. The motions of these have furnished us with a knowledge of the seasons; and they also supply us with an accurate measure of the smaller intervals. The untutored savage computes his time by the falls of snow or the progress of vegetation; the more advanced in the arts and knowledge of life employs moons or months as the units of his reckoning; while those who have made a still greater progress in civilization, add years and days, with their subdivisions, to their scale of time. But that these last may harmonize with each other, as well as each be of individual utility, an application of the principles of astronomy is necessary for their regulation. Hence arose the calendar, by which our civil affairs, at least as far as they depend upon the divisions of time, are conducted and thus it is that the movements of the celestial bodies, by a kind of imperceptible connexion, regulate the actions and affairs of men.
Chronology is another subject which has derived the most signal advantages from the science of astronomy. Those who have carried their researches into the annals of ancient nations, and endeavoured to investigate the events and transactions of past ages, are sensible of the uncertainty and obscurity that hover around them at every step. They find the narration of few facts accompanied by precise dates, and these are seldom the same in different authors.
But even here the torch of astronomical science illumes the perplexing labyrinth, and shows some points in the regions over which darkness had brooded for so many ages, and presents, as it were, the refreshment of repose to the weary and bewildered mind, until it is conducted to a degree of certainty unattainable without its aid. And it deserves to be remarked, that here even ignorance and superstition are, by the powerful influence of astronomy, rendered subservient to science and truth; as it is from the records which the ancients have left of the eclipses, which were then equally the terror of indi viduals and of nations, that we are enabled to deter mine the precise time at which they took place. It was by means of his astronomical knowledge that the celebrated Dr. Halley determined the very day and hour on which Julius Cæsar landed in Great Britain; and it has lately been shown by F. Baily, Esq. (see the Philosophical Transactions), that the great solar eclipse which terminated the six years" war between the Medes and the Lydians, as men→ tioned by Herodotus, happened on the 30th of September, six hundred and ten years before the christian era. Hence, if the date of some memorable event mentioned by the historian were entirely lost, but the relation of the fact accompanied by an account of some remarkable eclipse, the astronomer, by his knowledge of the celestial motions, would easily determine the precise time at which it happened.
These advantages, however, are not merely confined to the subjects we have enumerated: Navigation and Geography, as sciences, owe their very existence to astronomy. Navigation existed as an art long before it had any claim to the title of a science; and during these ages the mariner coasted along the shore, or confined himself to the crossing of narrow seas, without daring to lose sight of land and commit himself to the mercy of the winds and the waves. "It was astronomy that first inspired him with this
confidence, and taught him to conduct his vessel, with safety, through immense oceans, which had never before been traversed by man.
In this difficult and hazardous enterprise it is not sufficient for him to know the position of the port he designs to visit; he must also be able, at all times, to find upon what part of the globe he is, how far he has sailed, and what course he must pursue during the rest of the voyage. But these particulars can only be known from observations, and an accurate knowledge of the celestial motions.' Independently of this knowledge, therefore, Vasco de Gama would never have doubled the Cape of Good Hope, and opened a channel for the riches of India to flow into the stores of Europe; Columbus would not have disclosed the western world; nor Cook have circumnavigated the globe, and visited the polar regions of the south.
Geography and Navigation are twin sisters-inseparable companions; and whatever improves the one contributes to the perfection of the other. The ideas of latitude and longitude were first transferred from the heavens to the earth, when it was conceived that the same means by which the positions of the heavenly bodies had been indicated were equally applicable in fixing the situations of places on the surface of the terrestrial globe. When science had thus, as it were, assumed the helm, every fresh effort of navigation every daring enterprise of the mariner, added something to our knowledge of the globe. Countries were disclosed which had been hidden from the creation, and people discovered whose very existence was previously unsuspected; till almost every region has now been explored, and the productions of the earth conveyed from one extremity to the other.
But the influence of astronomy extends beyond the common affairs of life, in its tendency to enlarge the capacities of man, and increase the powers and penetration of his understanding. It dissipates the
superstitious notions and vain fears to which he is naturally prone; it expands the mind by the vastness of the views and objects it presents; and stores it with the most sublime and exalted ideas, not only of the works of creation, but of their all-wise and infinitely beneficent Author.
In the earlier ages of the world, as well as among the less civilized part of mankind at the present day, the unusual phenomena of nature always excite a painful degree of terror and consternation. An eclipse of the Sun or Moon has frequently been regarded as portending the annihilation of the universe; and the sudden appearance of a comet, with its blazing tail, as the harbinger of divine vengeance. But, in proportion as causes are understood, effects cease to be portentous; and astronomy has now happily banished such vain terrors, and enabled all the well-informed part of society not only to look upon comets and eclipses with tranquility and composure, but to derive both pleasure and instruction from those very phenomena which ignorance and apprehension had converted into causes of dismay.
Astrology is likewise another malady of untutored minds, by which the dark ages and places of the world have always been infested, and which astronomy has proved the most effectual means of eradicating. The cause of humanity is therefore under the most lasting obligations to this irradiating science, and to those individuals who have been so indefatigable in exploring the heavens, and rendering their discoveries subservient to the wants of life, and efficacious in exposing the fallaciousness of that dark and mysterious art which deludes the credulous, under pretence of searching into the secret designs of Providence, and explaining the hidden events of futurity.
The mind accustomed to contemplate the order and harmony of the celestial motions, and investigate the laws by which they are regulated; to examine the
magnitude of these immense orbs, and reflect upon the inconceivable velocity and undeviating accuracy with which they perform their revolutions, can hardly fail of expanding with the subject, or of having its erratic wanderings checked, and its tumultuous passions awed into subjection, by the grandeur and majestic sublimity of the scene. On this account, the wisest and greatest men of all ages have uniformly confessed themselves charmed with the beauties of this science. Poets, philosophers, and historians, have been emulous in its praises. Poets, in particu lar, have bestowed their highest encomiums on astronomy, which has furnished them with some of the noblest images, and the most exalted descriptions, that language can boast. A volume might easily be filled with specimens of this kind; but we shall only give the following beautiful simile from our immortal MILTON, describing the shield of Satan, in the first book of his inimitable Paradise Lost.
The broad circumference
Hung on his shoulders like the Moon, whose orb
How admirably is this study calculated to impart the most exalted ideas of the works of creation! and thence to lead the contemplative mind, by almost imperceptible gradations,
Through Nature up to NATURE'S GOD!
For, wherever we turn our eyes, design and contrivance meet our view; wisdom in selecting, power in impelling, and superintendence in controuling, this stupendous machinery of the universe constantly arrest the attention. The learned Dr. PALEY, after taking a perspicuous view of the nature of astronomy, and contrasting it with the limited powers and duration of man, judiciously observes,
After all, the real subject of admiration is, that