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432

Militia, Revenue, Taxes, Damages by the War, &c.

434

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448

Population, Character, Religion, Literature, &c.

450

Indians, Islands, History

452, 453

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DIRECTIONS FOR THE BINDER.

The MAP of the Southern States to front the TITLE.

The MAP of Northern States, page 33.

TABLE of Distances between the principal Towns in America

to be placed at the end of the work.

INTRO-

INTRODUCTION.

A

OF ASTRONOMICAL GEOGRAPHY.

COMPLETE knowledge of Geography, cannot be obtained without fome acquaintance with Aftronomy. This Compendium, therefore, will be introduced with a short account of that Science.

Aftronomy treats of the heavenly bodies, and explains their motions, times, diftances and magnitudes. The regularity and beauty of these, and the harmonious order in which they move, fhew that their Creator and Preferver poffeffes infinite wisdom and power.

Aftronomy was first attended to by the Shepherds, on the beautiful plains of Egypt and Babylon. Their employment led thein to contemplate the ftars. While their flocks, in the filence of the evening, were enjoying fweet repose, the spangled fky would naturally invite the attention of the Shepherds. The obfervation of the heavenly bodies afforded them amufement, and at the fame time affifted them in travelling in the night. A ftar guided the Shepherds to the manger where our bleffed Saviour was born. By the aid of a lively imagination, they diftributed the ftars into a number of conftellations or companies, to which they gave the names of the animals which they reprefented.

Of the Planets.] The fun is furrounded with feven spherical, opaque bodies, called Planets or wandering stars, which revolve about him as their centre at different distances, and in different periods, as exhibited in the following

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* From aftron, a ftar; and nomos, the law or rule.
+ Thefe fquare miles are as computed by ancient aftronomers:

B

The

The feven planets mentioned in the table are called primary planets; for befides these there are ten other bodies called fecondary planets, moons, or fatellites, which all revolve round their primaries from weft to eat, and at the fame time are carried along with them round the fun, as follows:

The earth has one fatellite, viz. the moon ), which performs her revolution in 29d. 12h. 44m. at the distance of about 60 femidiameters of the earth, or 209,100 miles, and is carried with the earth round the fun once in a year.

Jupiter has four moons; Saturn has five, and is alfo encompassed with a broad ring. The diameter of the ring is to the diameter of Saturn, as 9 to 4, and the space between the body of Saturn and the ring, is equal to the breadth of the ring.

The motion of the primary planets round the fun, and alfo the motion of the fatellites round their primaries, are called their annual motions. Befides this annual motion, they revolve round their own axes from west to east, and this is called their diurnal motion.

The lately discovered planet Herfchel, was firft obferved in 1782, by that celebrated aftronomer William Herschel, LL.D. F. R. S. In Great-Britain, it is called Georgium Sidus; but in France and America it has obtained the name of Herfchel, in honour to its learned discoverer.

Comets.] The comets are large opaque bodies, which move in very elliptical orbits, and in all poffible directions. Some revolve from west to caft; fome from eaft to weft; others from fouth to north; or from north to fouth. Their orbits have very different inclinations to the ecliptic. Some have conjectured, that the comets were intended by the All-wife Creator, to connect fyftems, and that each of their several orbits includes the fun, and one of the fixed stars. The figures of the comets are very different. Some of them emit beams on all fides like hair, and are called hairy comets. Others have a long, fiery, tranfparent tail, projecting from the part which is oppofite to the fun. Their magnitudes alfo are different. Some appear no bigger than fars of the first magnitude; others larger than the They are fuppofed to be folid bodies, and very dense; for fome of them in their nearest approach to the fun, were heated, according to Sir Ifaac Newton's calculation, 2000 times hotter than red hot iron; a degree of heat which would vitrify, or diffipate any matter known to us.

moon.

The number of comets belonging to our fyftem is not certainly known. Twenty-one have been feen. Of thefe, the periods of three only have been afcertained with accuracy. One appeared in the years 1531, 1607, 1682, and 1758; its period is 75 years. Another was feen in 1532 and 1661. The third appeared laft in 1680, whofe period being 575 years, cannot be expected to return until the year 2255.

Of the Solar-Syftem.] The feven planets, with their ten fatellites and the comets, conftitute the Solar, or as it is fometimes called, the Copernican System, in honour of Copernicus, a native of Poland, who adopted the Pythagorean opinion of the heavenly bodies, and published it to the world in 1530. This is now univerfally approved as the true fyftem. It has received great improvements from Gallileo, Sir Ifaac Newton, Dr. Halley, and other philofophers in almost every' age.

Of

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