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Of the fixed Stars.] The solar fyftem is surrounded with the fixed stars ; so called, because they at all times preserve the same situation 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 immense dillance from us. Although their distance is not certainly known, yet it is the general opinion of altronomers, that they are at leait 100,000 times farther from us, than we are from the sun; and that our sun viewed from a fixed star, would appear no bigger than a star does to us. A sound 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 Aying at the rate of 480 miles an hour, would not reach us in 700,000 years. Light, which is transmitted from one body to another almost instantaneouly, takes up more time in paffing from the fixed stars to this earth, than we do in making a voyage to Europe ; so that if all the fixed stars were now ftruck out of existence, they would appear to us to keep their stations for several months yet to come. It is impoffible, therefore, that they should borrow their light from the sun, as do the planets.
The number of stars, visible to the naked eye at any one time, in the upper hemisphere, is not more than a thousand. A thousand more are supposed to be visible in the lower hemisphere; and by the help of a telescope, a thousand more have been discovered ; so that the whole number of stars are reckoned at 3000. They are distinguished from the planets by their twinkling.
To consider these stars designed merely to decorate the sky, and form a rich and beautiful canopy for this earth, would be derogatory to the wisdom of the Creator. Astronomers therefore, with much reason, have considered the fixed stars as so many suns, attended wirh a number of revolving planets, which they illuminate, warm and cherish.
If this be true, there are as many systems, as'there are fixed stars. These may also revolve round one common centre, forming one immense system of systems. All these systems, we may conceive, are filled with inhabitants suited to their respective climes ; and are so many theatres, on which the Great Creator and Governor of the Universe displays his infinite power, wisdom and goodness.--Such a view of the starry heavens must fill the mind of every beholder, with sublime, magnificent, and glorious ideas of the Creator.
Of the EAR TH.
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; so that its diameter from eaft to weft, is about thirty miles longer than from north to south. Its figure is an oblate spheroid. It moves round the sun in
This is called the earth's annual motion, to which we are indebted for the differ. ence 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 since 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
The earth is 25,038 miles in circumference; and by turning on its axis once in twenty-four hours from west to east, causes a continual fucceffion of day and night, according as either fide is turned to or from the sun; and occasions an apparent motion of the sun and heavenly bodies from east to west. 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 Anson, Captain Cook and others*. Secondly, From its fhadow in eclipses of the moon, which shadow is bounded by a circular line.
As the earth is round and habitable on all sides, it will doubtless appear strange, that persons can stand directly oppofite to us on the under fide.
* Magellan failed from Seville in Spain, under the auspices of Charles V. foth of August, 1519; and kaving discovered the Magellanic Streights in South America, be crossed the Pacific Occean, and arrived at the Philippine Isands where he quas poisoned. His ship returned by way of the Cape of Good Hope, 8th of September 1522.
Sir Francis Drake failed from Plymouib, 13th December 1977-entered the Pacific Ocean, and steering round America, returned November 3d, 1580 He was a man of great generosity. The boots which he took, and even the wedges of gold given him in return for his presents to Indian chiefs, be divided in just proportional shares with the common sailors.
Thomas Cavendith failed from Plymouth, with two smoll frips, tbe 11 of Auguft, 1586--passed through the Streights of Magellan—took many rich prises along the coasts of Chili and Peru; and near California popesed himself of the St. Annan Acapulco ship, with a cargo of immense 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, successively failed round the globe.
Lord Anson failed in September, 1740--doubled Cape Horn in a dangerous season---loft most of his men by the scurvy, and with only one remaining ship, (the Centurion,) crossed the Great Pacific Ocean, which is 10,000 miles over - - took a Spanish galleon, on her pasage from Acapulco to Manilla, and returned home in June 1744.
Biron-Bouganville, a Frenchman--Wallis and Carteret, fucceflively circumnavigated the globe, between the years 1764 and 1769.
Captain Cook, in the ship Endeavour, sailed from Plymouth the 26th of August, 1768, and after a mol satisfactory voyage, returned the 12th of June, 1771. He set out on a second voyage the 14th of February, 1776-made many important discoveries, and was killed on the island of Owhy hee by the natives, the 14th of February, 1779. His ships under the command of Captain Clerka returned the 16th of O&ober, 1780.
But this will easily be conceived, when it is considered that the earth attracts all bodies, on or near its surface, towards its centre equally on all fides. If so, the people who are opposite to us ftand just 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 shall think the same at ten o'clock this evening, when the earth shall have turned half round, because we shall then perceive no difference of posture. We shall then be exactly in the position of those persons who now stand on the opposite side of the earth. Since they are as strongly attracted towards the centre of the earth as we are, they can be in no more danger of falling downward, than we are at present of falling upwards.
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 situation.
In order to determine the situation of places on the globe, it is supposed to be circumscribed by several imaginary circles. Each circle is divided into 360 equal parts, called degrees; each degree is divided into 60 minutes, and each minute into 60 seconds.
Axis of the Earth.] The axis of the earth is an imaginary line passing through its centre from north to south. The extreme points of the axis are called the poles.
Circles.] A circle passing through the centre of a globe, and thereby dividing it into two equal parts or hemispheres, 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 small 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 encompasses the middle of the earth, dividing the northern half from the southern. This line is often called the equino&tial, because, when the sun appears therein, the days and nights are equal in all parts of the world. From this line latitude is reckoned.
Meridian. ] This circle is represented on the artificial globe by a brass ring, and is divided into 360 degrees. It passes through the poles of the earth, and the zenih, and the nadir, crossing the equator at right angles, and dividing the globe into eastern and weftern hemispheres. It is called meridian from the Latin meridies, mid-day ; because when the sun comes to the south 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 east or west. Geographers assume one of the meridians for the first; commonly that which passes through the metropolis of their own country. The meridian of Philadelphia is the first for Americans ; that of London for the English; and that of Paris for the French.
3 Gemini 4. Cancer 5 Leo
Ecliptic.] The ecliptic is a great circle, in whose plane the earth performs her annual revolution round the sun ; or in which the sun, seems to move round the earth once in a year. This circle is called the Ecliptic, from the word Eclipse, because no eclipse 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 equaior of 23o 30, and intersects it in two opposite parts called the equino&ial points, because when the sun is in either of these points he has no declination, and shines equally to both poles, and the day is then equal to the night all over the world. The times when the sun passes through these points, are the 21st of March, and the zift 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 signs. These begin at the vernal intersection of the ecliptic with the equator, and are numbered from west to eaft. The names and characters of the signs, with the months in which the sun enters them, are as follow : Latin names of English names. Charac Months in which the the signs.
ters. sun enters them. The Ram
March 2 Taurus The Bull
November 10 Capricornus The Goat
December 11 Aquarius The Water-Bearer
January 12 Pisces The Fishes
February Zodiac.] If two circles were drawn parallel to the ecliptic, at the distance of eight degrees on each side of it, the space, 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 hemispheres. There are, geographically speaking, two horizons, the sensible and the rational. The sensible horizon is that circle which limits our prospect; where the sky and the land and water appear to meet. The rational or real horizon, is a circle whose plane passes 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, welt, north, and south, 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 distinguish them from
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 side of it. These circles form the limits of the ecliptic, or the sun's declination from the equator. That which is in the northern hemisphere, 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 sign Capricorn. On the 21st of June the sun is in Cancer, and we have the longest day. On the 21st of December the sun is in Capricorn, and we have the shortest day. They are called tropics, from the Greek word trepo, to turn, because when the sun 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 distance of 23° 30'. The northern is called the Arêtic circle, from Arfus, or the bear, a constellation situated near that place in the heavens ; the southern, being opposite to the former, is called the Antarctic circle. The polar circles bound the places where the sun sets daily. Beyond them the sun revolves without setting.
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 sun, being always over some 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 south 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, so 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 surface, included between the equator: and a parallel of latitude, or between two parallels of such 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 sun's continuance above the horizon without setting, 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 distance of 80 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.