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Of the fixed Stars.] The folar fyftem is furrounded with the fixed ftars; fo called, because they at all times preferve the fame fituation in regard to each other. These stars, when viewed with the best telescopes, appear no larger than points, which proves that they are at an immenfe diftance from us. Although their distance is not certainly known, yet it is the general opinion of aftronomers, that they are at least 100,000 times farther from us, than we are from the fun; and that our fun viewed from a fixed star, would appear no bigger than a ftar does to us. A found would not reach us from Sirius, or the dog-ftar, which is nearer to this earth than any of the fixed stars, in 50,000 years. A cannon ball flying at the rate of 480 miles an hour, would not reach us in 700,000 years. Light, which is tranfmitted from one body to another almoft inftantaneoufly, takes up more time in paffing from the fixed stars to this earth, than we do in making a voyage to Europe; fo that if all the fixed ftars were now ftruck out of exiftence, they would appear to us to keep their stations for several months yet to come. It is impoffible, therefore, that they fhould borrow their light from the fun, as do the planets.

'The number of stars, visible to the naked eye at any one time, in the upper hemifphere, is not more than a thousand. A thousand more are fuppofed to be vifible in the lower hemifphere; and by the help of a telefcope, a thousand more have been discovered; fo that the whole number of stars are reckoned at 3000. They are distinguished from the planets by their twinkling.

To confider these ftars defigned merely to decorate the sky, and form a rich and beautiful canopy for this earth, would be derogatory to the wifdom of the Creator. Aftronomers therefore, with much reafon, have confidered the fixed stars as fo many funs, attended with a number of revolving planets, which they illuminate, warm and cherish. If this be true, there are as many fyftems, as there are fixed flars. Thefe may also revolve round one common centre, forming one immenfe fyftem of systems. All these fyftems, we may conceive, are filled with inhabitants suited to their refpective climes; and are fo many theatres, on which the Great Creator and Governor of the Universe displays his infinite power, wisdom and goodness. Such a view of the ftarry heavens muft fill the mind of every beholder, with fublime, magnificent, and glorious ideas of the Creator.

Of the EARTH.

H AVING taken a cursory view of the heavenly bodies, we proceed

to give a more particular account of the planet which we inhabit.

The Earth, though called a globe, is not perfectly round, but is widened at the equator, and flattened at the poles; fo that its diameter from caft to weft, is about thirty miles longer than from north to fouth. Its figure is an oblate spheroid. It moves round the fun once in a year. This is called the earth's annual motion, to which we are indebted for the difference in the length of the days and nights, and for the variety in the seasons. The diameter of the earth's orbit, is 190,346,000 miles. And fince the circumference of a circle, is to its diameter, as 355 is to 113, the circumference of the earth's orbit is 597,987,646 miles. And as the earth de

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fcribes this orbit in 365 days and 6 hours, (or in 8766 hours,) it is plain that it travels at the rate of 68,217 miles every hour; fo that its velocity in its orbit is at least 142 times as great as the velocity of a cannon-ball, fuppofing the ball to move through eight miles in a minute, which it is found to do nearly. At this rate it would take 22 years and 228 days for

a cannon ball to go from this earth to the fun.

The earth is 25,038 miles in circumference; and by turning on its axis once in twenty-four hours from weft to eaft, caufes a continual fucceffion of day and night, according as either fide is turned to or from the fun; and occafions an apparent motion of the fun and heavenly bodies from east to weft. This is called the earth's diurnal, or daily motion, by which the inhabitants on the equator are carried 1040 miles every hour.

That the earth is round like a globe is evident: First, From its having been circumnavigated, or failed round by Magellan, Sir Francis Drake, Lord Anfon, Captain Cook and others*. Secondly, From its fhadow in eclipfes of the moon, which fhadow is bounded by a circular line.

As the earth is round and habitable on all fides, it will doubtlefs appear ftrange, that persons can stand directly oppofite to us on the under fide.

*Magellan failed from Seville in Spain, under the aufpices of Charles V. toth of August, 1519; and having discovered the Magellanic Streights in South America, be croffed the Pacific Occean, and arrived at the Philippine Islands where be avas poisoned. His hip returned by way of the Cape of Good Hope, 8th of September 1522.

Sir Francis Drake failed from Plymouih, 13th December 1577-entered the Pacific Ocean, and steering round America, returned November 3d, 1580 He was a man of great generafity. The booty which he took, and even the wedges of gold given him in return for his prefents to Indian chiefs, he divided in juft proportional fhares with the common failors.

Thomas Cavendish failed from Plymouth, with two small fhips, the ft of Auguft, 1586-paffed through the Streights of Magellan-took many rich prizes along the coafts of Chili and Peru; and near California poffeffed himself of the St. Annan Acapulco hip, with a cargo of immenfe value. He completed the circumnavigation of the globe the 9th of September, 1588.

Between the years 1598 and 1626, Oliver de Nort, of Utrecht, James Mahu, George Spillenberger, a Fleming, William Schouten, a Hollander, and James the Hermit, fucceffively failed round the globe.

Lord Anfon failed in September, 1740-doubled Cape Horn in a dangerous feafon-loft most of his men by the fcurvy, and with only one remaining ship, (the Centurion,) crofled the Great Pacific Ocean, which is 10,000 miles over — - took a Spanish galleon, on her paffage from Acapulco to Manilla, and returned home in June 1744.

Biron-Bouganville, a Frenchman-Wallis and Carteret, fucceffively circumnavigated the globe, between the years 1764 and 1769.

Captain Cook, in the fhip Endeavour, failed from Plymouth the 26th of August, 1768, and after a most fatisfactory voyage, returned the 12th of June, 1771. He fet out on a fecond voyage the 14th of February, 1776-made many important difcoveries, and was killed on the island of Owyhee by the natives, the 14th of February, 1779. His hips under the command of Captain Clerk, returned the 16th of October, 1780.

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But this will eafily be conceived, when it is confidered that the earth attracts all bodies, on or near its furface, towards its centre equally on all fides. If fo, the people who are oppofite to us ftand juft as firm as we do.

It is now ten o'clock in the morning, and we think we are standing upright on the upper part of the earth.-We fhall think the fame at ten o'clock this evening, when the earth shall have turned half round, because we shall then perceive no difference of pofture. We shall then be exactly in the pofition of thofe perfons who now ftand on the oppofite fide of the earth. Since they are as ftrongly attracted towards the centre of the earth as we are, they can be in no more danger of falling downward, than we are at prefent of falling upwards.

ARTIFICIAL GLOBE.

AN is a

N artificial globe is a round body, whofe furface is every where equally remote from the centre; and on which the external form of our habitable world is represented, and all the parts of the earth and water are described in their natural order, form, distance and fituation.

In order to determine the fituation of places on the globe, it is fuppofed to be circumfcribed by feveral imaginary circles. Each circle is divided into 360 equal parts, called degrees; each degree is divided into 60 minutes, and each minute into 60 feconds.

Axis of the Earth.] The axis of the earth is an imaginary line paffing through its centre from north to fouth. The extreme points of the axis are called the poles.

Circles.] A circle paffing through the centre of a globe, and thereby dividing it into two equal parts or hemifpheres, is called a great circle. Of these there are fix. The equator, the meridian, the ecliptic, the horizon, and two colures.

Circles dividing the sphere into unequal parts, are called fmall or lesser circles, of which there are four, the two tropics, and the two polar circles.

Equator.] The equator is that line or circle which encompaffes the middle of the earth, dividing the northern half from the fouthern. This line is often called the equinoctial, becaufe, when the fun appears therein, the days and nights are equal in all parts of the world. From this line latitude is reckoned.

Meridian.] This circle is reprefented on the artificial globe by a brafs ring, and is divided into 360 degrees. It paffes through the poles of the earth, and the zenith, and the nadir, croffing the equator at right angles, and dividing the globe into eaftern and weftern hemifpheres. It is called meridian from the Latin meridies, mid-day; because when the fun comes to the fouth part of this circle it is called noon, and the day is half spent. There are an infinite number of meridians, which vary as you travel eaft or weft. Geographers affume one of the meridians for the firft; commonly that which paffes through the metropolis of their own country. The meridian of Philadelphia is the firft for Americans; that of London for the English; and that of Paris for the French.

Ecliptic.]

Ecliptic.] The ecliptic is a great circle, in whofe plane the earth performs her annual revolution round the fun; or in which the fun, feems to move round the earth once in a year. This circle is called the Ecliptic, from the word Eclipfe, because no eclipfe of the fun or moon happens, but when the moon is in or near the plane of this circle. It makes an angle with the equator of 23° 30', and interfe&s it in two oppofite parts called the equinoctial points, because when the fun is in either of these points he has no declination, and fhines equally to both poles, and the day is then equal to the night all over the world. The times when the fun paffes through thefe points, are the 21st of March, and the 21ft of September: the former is called the vernal, the latter the autumnal equinox.

The ecliptic is divided into twelve equal parts, of thirty degrees each, called figns. These begin at the vernal interfection of the ecliptic with the equator, and are numbered from weft to eaft. The names and characters of the figns, with the months in which the fun enters them, are as follow:

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Zodiac.] If two circles were drawn parallel to the ecliptic, at the distance of eight degrees on each fide of it, the fpace, or girdle included between these two parallels, fixteen degrees broad, and divided in the middle by the ecliptic, will comprehend within it the orbits of all the planets, and is called the Zodiac.

Horizon.] The horizon is represented on the artificial globe by a broad wooden circle, dividing it into upper and lower hemifpheres. There are, geographically speaking, two horizons, the fenfible and the rational. The fenfible horizon is that circle which limits our profpect; where the fky and the land and water appear to meet. The rational or real horizon, is a circle whofe plane paffes through the centre of the earth, dividing it into upper and lower hemispheres.

The horizon is divided into four quarters, and each quarter into 90 degrees. The four quartering points, viz. eaft, weft, north, and fouth, are called the Cardinal points. The poles of the horizon are the zenith and the nadir. The former is the point directly over our heads; the latter the point directly under our feet.

Colures. The colures are two meridian lines which divide the globe into four quarters. They are called colures, to diftinguish them from

other

other meridians. They both pass through the poles of the world, and one of them through the equinoctial points Aries and Libra; the other through the folftitial points Capricorn and Cancer: The former is called the equinoctial, the latter the folftitial colure.

Tropics.] The tropics are two circles drawn parallel to the equator, at the distance of 23° 30' on each fide of it. These circles form the limits of the ecliptic, or the fun's declination from the equator. That which is in the northern hemifphere, is called the tropic of Cancer; because it touches the ecliptic in the fign Cancer; and that in the southern hemisphere, is called the tropic of Capricorn, because it touches the ecliptic in the fign Capricorn. On the 21ft of June the fun is in Cancer, and we have the longest day. On the 21ft of December the fun is in Capricorn, and we have the shortest day. They are called tropics, from the Greek word TREPŎ, to turn, because when the fun arrives at them, he returns again to the equator.

Polar Circles.] The two polar circles are described round the poles of the earth, at the diftance of 23° 30'. The northern is called the Artic circle, from Aros, or the bear, a conftellation fituated near that place in the heavens; the fouthern, being oppofite to the former, is called the Antarctic circle.-The polar circles bound the places where the sun sets daily. Beyond them the fun revolves without fetting.

Zones.] The tropics and polar circles divide the globe into five parts, called Zones, or Belts; viz. One torrid, two temperate, and two frigid zones.

The Torrid Zone, 47 degrees broad, is bounded by the tropics, and divided in the middle by the equator. It is called the torrid or burning zone, because the fun, being always over fome part of it, makes it extremely hot.

Each of the Temperate Zones is 43 degrees in breadth. The one which lies between the tropic of Cancer and the arctic circle, is called the north temperate zone; and the other, lying between the tropic of Capricorn and the antarctic circle, is called the fouth temperate zone. The mildness of the weather in these spaces, which are between the extremes of heat and cold, has acquired to them the name of temperate zones.

The two Frigid Zones, fo called on account of the extreme cold of those regions, are included between the polar circles and the poles. Each of them is 23° 30′ broad.

Climates.] By a number of other circles, drawn parallel to the equator, the earth is divided into climates.

A Climate is a tract of the earth's furface, included between the equator and a parallel of latitude, or between two parallels of fuch a breadth, as that the length of the day in the one, be half an hour longer than in the other. Within the polar circles, however, the breadth of a circle is fuch, that the length of a day, or the time of the fun's continuance above the horizon without fetting, is a month longer in one parallel, as you proceed northerly, than in the other.

Under the equator, the day is always twelve hours long. The days gradually increase in length as you advance either north or fouth from the equator. The space between the equator, and a parallel line drawn at the diftance of 8° 25' where the days are twelve hours and a half long, is called the first climate; and by conceiving parallels drawn in this manner, at the increase of every half hour, it will be found that there

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