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nize his acquaintance among the stars. He may find himself able to rccollect the names of the principal stars, and the uncouth forms by which the constellations are pictured out; but which of all the positions he has placed the globe in, is now so present to his mind that he is enabled to identify it with any portion of the visible heavens?
He looks in vain to see,
"Lions and Centaurs, Gorgons, Hydras rise,
And gods and heroes blaze along the skies."
He finds, in short, that the bare study of the globe is one thing, and that of the heavens quite another; and he arrives at the conclusion, that if he would be profited, both must be studied and compared together. This, since a class is usually furnished with but one globe, is impracticable. In this point of view also, the maps are preferable.
I have endeavoured to teach the Geography of the heavens in nearly the same manner as we teach the Geography of the earth. What that does in regard to the history, situation, extent, population and principal cities of the several kingdoms of the earth, I have done in regard to the constellations; and I am persuaded, that a knowledge of the one may be as easily obtained, as of the other. The systems are similar. It is only necessary to change the terms in one, to render them applicable to the other. For this reason, I have yielded to the preference of the publisher in calling this work "Geography of the Heavens," instead of URANOGRAPHY, or some other name more etymologically apposite.
That a serious contemplation of those stupendous works of the Most High, which astronomy unfolds, is calculated above all other departments of human knowledge, to enlarge and invigorate the powers of religious contemplation, and subserve the interests of rational piety, we have the testimony of the most illustrious characters that have adorned our race.
If the work which I now submit, shall have this tendency, I shall not have written in vain. Hitherto, the science of the stars has been but very superficially studied in our schools, for want of proper helps. They have continued to gaze upon the visible heavens without comprehending what they saw. They have cast a vacant eye upon the splendid pages of this vast volume, as children amuse themselves with a book which they are unable to read. They have caught here and there, as it were a capital letter, or a picture, but they have failed to distinguish those smaller characters on which the sense of the whole depends. Hence, says an eminent English Astronomer, A comprehensive work on Descriptive Astronomy, detailing, in a popular manner, all the facts which have been ascertained respecting the scenery of the heavens, accompanied with a variety of striking delineations, accommodated to the capacity of youth, is a desideratum." How far this desirable end is accomplished by the following work, I humbly leave to the public to decide.
Hartford, Feb. 1833.
ADVANTAGES OF THE STUDY OF ASTRONOMY
THOMAS DICK, LL. D.
ASTRONOMY is a science which has, in all ages, engaged the attention of the poet, the philosopher, and the divine, and been the subject of their study and admiration. Kings have descended from their thrones to render it homage, and have sometimes enriched it with their labours; and humble shepherds, while watching their flocks by night, have beheld with rapture the blue vault of heaven, with its thousand shining orbs moving in silent grandeur, till the morning star announced the approach of day.-The study of this science must have been co-eval with the existence of man. For there is no rational being who, for the first time, has lifted his eyes to the nocturnal sky, and beheld the moon walking in brightness among the planetary orbs and the host of stars, but must have been struck with awe and admiration at the splendid scene, and its sublime movements, and excited to anxious inquiries into the nature, the motions, and the destinations of those far-distant orbs. Compared with the splendour, the amplitude, the august motions, and the ideas of infinity which the celestial vault presents, the most resplendent terrestrial scenes sink into inanity, and appear unworthy of being set in competition with the glories of the sky.
Independently of the sublimity of its objects, and the pleasure arising from their contemplation, Astronomy is a study of vast utility, in consequence of its connexion with terrestrial arts and sciences, many of which are indebted to the observations and the principles of this science for that degree of perfection to which they have attained.
Astronomy has been of immense utility to the science of
for it is chiefly in consequence of celestial observations that the true figure of the earth has been deinonstrated and its density as certained. It was from such observations, made on the mountain Schehallien in Scotland, that the attraction of mountains was determined. The observations were made by taking the meridian distances of different fixed stars near the zenith, first on the south, and afterwards on the north side of the hill, when the plumb line of
the Sector was found, in both cases, to be deflected from the perpendicular towards the mountain; and, from calculations founded on the quantity of this deflection, the mean density of the earth was ascertained. It was likewise by means of celestial observations that the length of a degree of the meridian was measured, and the circumference of the globe, with all its other dimensions accurately ascertained; for, to ascertain the number of degrees between any two parallels on the Earth's surface, observations must be taken, with proper instruments, of the sun or of the stars, at different stations; and the accurate measurement of the terrestrial distance between any two stations or parallels, partly depends on astronomical observations combined with the principles and operations of Trigonometry. So that without the aids of this science. the figure and density, the circumference and diameter of our terrestrial habitation, and the relative position of places on its surface, could never have been ascertained.
Astronomy is likewise of great utility to the art of
without a certain knowledge of which the mariner could never have traced his course through pathless oceans to remote regionsthe globe would never have been circumnavigated, nor an intercourse opened between the inhabitants of distant lands. It is of essential importance to the navigator, not only to know the situation of the port to which he is bound, but also to ascertain with precision, on what particular portion of the terraqueous globe he is at any time placed-what course he is pursuing-how far he has traveiled from the port at which he embarked-what dangerous rocks or shoals lie near the line of his course-and in what direction he must steer, in order to arrive, by the speediest and the safest course, to his destined haven. It is only, or chiefly, by astronomical observations that such particulars can be determined. By accurately observing the distance between the moon and certain stars, at a particular time, he can calculate his distance East or West from a given meridian; and, by taking the meridian altitude of the sun or of a star, he can learn his distance from the Equator or from the poles of the world. In such observations, a knowledge of the constellations, of the polestar, and of the general positions of all the stars of the first and second magnitude, is of particular importance; and, therefore, a navigator who is unacquainted with the science of the heavens, ought never to be appointed to conduct a ship through the Indian, the Atlantic, or the Pacific oceans, or through any portions of the sea which is not within sight of land. By the observations founded on astronomical science, which have been made in different regions, by mariners and travellers of various descriptions, the latitudes and longitudes of the principal places on the globe, and their various bearings and relations have been determined, so that we can now take a view of the world we inhabit in all its multifarious aspects, and direct our course to any quarter of it, either for business, for pleasure, or for the promotion of philanthropic objects. Thus, Astronomy has likewise become of immense utility to Trade and Commerce, in opening up new emporiums for our
manufactures, in augmenting and multiplying the sources of wealth, in promoting an intercourse between the most distant nations, and enabling us to procure, for our accommodation or luxury, the productions of every climate. If science has now explored almost every region; if Politics and Philosophy have opened a communication between the remotest inhabitants of the globe; if alliances have been formed between the most distant tribes of mankind; if Traffic has explored the multifarious productions of the earth and seas, and transported them from one country to another, and, if heathen lands and barbarous tribes have been "visited with the Day-spring from on high, and the knowledge of salvation,"-it is owing to the aids derived from the science of the stars, without which the continents, the islands, and the different aspects of our globe would never have been explored by those who were separated from them by intervening oceans.
This science has been no less useful to
and to the cultivators of the earth. The successful cultivation of the soil depends on a knowledge of the course of the sun, the exact length of the seasons, and the periods of the year most proper for the operations of tillage and sowing. The ancients were directed in these operations, in the first instance, by observing the courses of the moon, and that twelve revolutions of this luminary corresponded nearly with one apparent revolution of the sun. But finding the coincidence not exact, and that the time of the seasons was changing-in order to know the precise bounds of the sun's annual course, and the number of days corresponding to his apparent yearly revolution, they were obliged to examine with care what stars were successively obscured in the evening by the sun, or overpowered by the splendour of his light, and what stars were beginning to emerge from his rays, and to re-appear before the dawn of the morning. By certain ingenious methods, and numerous and attentive observations, they traced out the principal stars that lay in the line of the sun's apparent course, gave them certain names by which they might be afterwards distinguished, and then divided the circle of the heavens in which the sun appears to move, first into quadrants, and afterwards into 12 equal parts, now called the signs of the Zodiac, which they distinguished by names corresponding to certain objects and operations connected with the different seasons of the year. Such were the means requisite to be used for ascertaining the length of the year, and the commencement of the different seasons, and for directing the labours of the husbandman; -and, were the knowledge of these things to be obliterated by any extensive moral or physical convulsion, mankind would again be under the necessity of having recourse to astronomical observations for determining the limits of the solar year, and the course of the seasons. Although we find no difficulty, in the present day, and require no anxious observations, in determining the seasons, yet, before astronomical observations were made with some degree of accuracy, the ancient Greeks had to watch the rising of Arcturus the Pleiades and Orion, to mark their seasons, and to determine the