Page images
PDF
EPUB

ELEMENTS OF GEOGRAPHY.

DEFINITIONS.

GEOGRAPHY is a Science, which deseribes the fig. ure, motion, magnitude, and component parts of the earth; the situations, extent, and appearances of the various parts of its surface; its productions, animal and vegetable; its natural and political divisions ; and the history, manners, customs, and religion of its inhabitants.

The Science, which treats of the heavenly bodies, and explains their motions, magnitudes, periods, and distances, is called ASTRONOMY.

These two Sciences are so intimately connected, that a competent knowledge of Geography is unattainable, with out some previous acquaintance with Astronomy.

We shall commence this work with the following brief historical account of the origin, progress, and improvement of Geography and Astronomy. HISTORY OF GEOGRAPHY AND ASTRONOMY.

GEOGRAPHY, like every other science, at its beginning was very imperfect, and arrived at its present improved, though far from perfect state, by slow advances. The early geographers, being destitute of 'mathematical instru. ments, and unable to make astronomical observations, bę. gan first to determine the situation of places, according to climates ; which they fixed from the form and color of the people and animals, which were to be found in those different countries. The appearance of negroes,

and of the large animals, such as the rhinoceros, and the ele. phant, suggested to them where to fix the limits of the Lorrid or burning zone. For reason, said they, points out to us, that similar animals and plants appear in the same

one.

temperature of the elements, and are produced according to the similar state of the air or climate under the same parallels, or a like situation equally distant from either pole. This was the first rude outline of Geography.

The BABYLONIANS and EGYPTIANs soon after adopted the method of determining the situations of places, or their distance from the equator, by observing the length of their longest and shortest day, which they determined by means of a kind of sun-dial, called a gnomon. All the places, for instance, where the longest day was just fourteen hours, or where the shortest day was ten hours, were of course, at the same distance from the

equator. Astronomy, as a science, was first cultivated by the Egyptians, Phenicians, and Chaldeans. From them the Greeks derived their knowledge of this science.

The first of the Greeks, who laid the foundation of Astronomy, was THALES, born at Miletus, 641 years before Christ. He explained the cause of eclipses, and predicted

He taught that the earth was round, which before had been considered as an extensive plane, while the sun and stars moved round it. He divided the earth into five zones, discovered the solstices and equinoxes, and divid. ed the year into 365 days. He travelled into Egypt, in quest of knowledge, and measured the height of the pyramids.

PYTHAGORAS, the scholar of Thales, taught publicly the doctrine, common in his time, that the earth was the cena tre of the universe ; but to his scholars, he communicated his real opinions, which were similar to those since adopted by Copernicus ; that the earth and all the planets move round the sun as their centre ; which doctrine he is supposed to have derived from the astronomers of India.

PHILOLAUS, the scholar of Pythagoras, and ARCHYTAS of Tarentum,

according to a passage in the works of CiceTo, first taught publicly the diurnal or daily motion of the earth, and its annual or yearly motion round the sun. This passage is said

to have suggested to Copernicus the first idea of that system which he established.

DEMOCRITUS was the first who taught that the milky way is occasioned by the confused light of an infinity of stars, which is the doctrine still maintained by the best of philosophers. PLATO, and ARISTOTLE and EUDOXUS, the

[ocr errors]

scholars of Plato, contributed much to the improvement of Astronomy.

But the greatest improvements in this science were made in the famous astronomical school of Alexandria, founded by Ptolemy Philadelphus, about 320 years before Christ. The first in this school, who distinguished them. selves, were TIMOCHARIS and ARISTILLUS, who introduced the manner of determining the positions of the stars, according to their longitudes and latitudes, taken with respect to the equator. This led HIPPARCHUS, afterwards, by an easy transition of thought, to divide the earth by lines of latitude and longitude, in the same manner as Timocharis and Aristillus had the heavens. Hence, with great justice, he is universally allowed to have fixed the first solid foundation of Geography, by uniting it to Astronomy, and so rendering its principles self-evident and invariable. This most illustrions astronomer Aourished between 160 and 125 years before Christ.

The celebrated ERATOSTHENES, author of the Armillary Sphere, who first determined with exactness, the circumferenceof the earth, by measuring a degree of the meridian, and discovering the true distance of the sun and moon from the earth, Hourished 100 years before Hipparchus. In a valuable map, which he constructed, he first introduced å regular parallel of latitude.

Among the Romans, JULIUS CÆSAR, by his reformation of the Roman Calendar, and by his knowledge of the principles of Astronomy, contributed more than any other person of that nation, to the advancement of Astronomy.

The last illustrious Astronomer and Geographer of the Alexandrian school, was PTOLEMY, born at Ptolemais, in Egypt. He flourished under Adrian aud the Antonines. He supposed the carth to be in the centre of the system, and the heavenly. bodies to move round it.

In respect to Maps, those on record before the time of Hipparchus, except the single map of Eratosthenes, before mentioned, were little more than rude outlines and topographical sketches of different countries.

The earliest maps were those of Sesostris, an Egyptian king, who, having traversed a great part of the earth, recorded his marches in maps, and gave copies of them, not

[graphic]
[merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][ocr errors]

only to the Egyptians, but to the Scythians, to their great astonishment.

The first Grecian map, was that of ANAXIMANDER, supposed to have been a general map of the then known world, and styled by Hipparchus, the ancient map.

ARISTAGORAS, of Miletus, constructed a map of the Mediterranean sea, and its coasts, and more particularly of the lesser Asia, extending to the middle of Persia.' It contained one straight line called the Royal Highway, taking in all the stations or places of encampment, 111 in number, from Sardis to Susa, a distance of 1635 miles ; so that it was little more than an itinerary or a sorl of directory to ar. mies and travellers. These itinerary maps were indispensa. ble in all armies; and from those which Alexander caus. ed to be made, with great care, for the use of his army in their various and extensive marches, the science of Geog. raphy received most important advantages, and, from this period, assumed a new face and form.

War, in ancient times, was made subservient to the ad. vancement of geographical knowledge. Every new war produced a new survey and itinerary of the countries, which were the scenes of action. The Romans, some time before the Christian era, became the conquerors, and consequently the surveyors, of a great part of the then inhabited world. Materials for Geography were accumulated by every additional conquest. Julius Cæsar ordered a general survey to be made of all the Roman Empire, by a decree of the senate ; the surveyors are said to have been men of great wisdom, and instructed in every branch of philosophy.

The Roman empire had been enlarged to its greatest extent, and all its provinces well known and surveyed, when Prolemy, in the days of Antoninus Pius, about 150 years before Christ, composed his system of Geography ; which, though full of mistakes and errors, arising necessarily from the infancy of the science and the ignorance of the age in which he lived, continued to be the only book of note and authority on this science, till the beginning of the 17th century.

For when science began to revive in Europe, after the Reformation by Luther and Calvin, and the invention of printing by Dr. Faust, in 1444, it was some time before the astronomers of that age were able to

[merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small]

obtain copies of Ptolemy's Geography ; and even then, it was with difficulty they could read and clear his manu. scripts of some of their groșsest errors. It required a still longer time before they could construct proper instru. ments for determining, with accuracy, the latitudes and longitudes of places.

It was not till COPERNICUS, TYCHO BRAHE, of Denmark, born in 1546, Kepler, of Germany, born in 1571, GALLILEU, of Italy, born in 1564, DESCARTES, of France, born in 1596, CASSINI of Nice, FLAMSTEAD, HALLEY, and Sir Isaac Newton, of England, had enlightened the world with their discoveries, that Astronomy and Geography were placed on their true foundation, and reduced to a tolerable degree of consistency and accuracy.

THE SOLAR SYSTEM.

The supposition of a certain disposition of the heavenly bodies, and the planetary orbits, is called a System of the World. The true System, or disposition of the planets, is called the Solar System. It is also called the Copernican System, from Copernicus, a Prussian. Several other systems, as the Plolemaić, and Tychonic, have, at different times, been promulgated to the world ; but are now universally exploded. The true solar system was taught by Pythagoras, 500 years before Christ; but the knowledge of it was nearly lost, when Copernicus revived it, in 1530.

This system supposes the sun to be in the centre, and the well known planets to revolve round him in the following order : Mercury, Venus, Earth, Mars, Jupiter, Saturn, Herschel.

The two first of these are called inferior planets, because they are nearer to the common centre of gravity of the system, than the earth, or are below the earth, with respect to that centre ; the other four are called superior, because, with respect to said centre, they are above the earth. Also the inferior planets are called interior, because their orbits are within that of the earth ; and the superior are called exterior, because their orbits are without the same.

These seven are called primary plane!s, to disı.nguish them from a number of other bodies; called stondary planets,

B

« PreviousContinue »