generally employed in catching, breaking in, and training as cavalry, the numerous herds of wild horses, which, since the settlement of the Spaniards, have multiplied prodigiously. The country is extremely fertile, so far as it has been cultivated; it produces cotton in great abundance, tobacco, and the herb called Paraguay; the latter is peculiar to this region, and an infusion of it is drunk in all the Spanish provinces, instead of tea.

There

are mines of gold, silver, copper, tin, and lead. In the western district there is a singular volcano, which might appear the palace of Eolus, where the winds were imprisoned, for they rush forth in the morning with surprising violence. Paraguay for some years was ruled by Dr Francia, a Spaniard, who set at defiance the efforts of the republicans of Buenos Ayres to subdue him; he died lately.

EXERCISES UPON SOUTH AMERICA.

WHERE is Colombia, Bolivia, La Plata, Patagonia, Brazil, Chili, Guiana, Paraguay, &c.

Where is Porto Bello, Lima, Buenos Ayres, Potosi, Rio Janeiro, Assumption, Paramaribo, Conception, Tolu, Bahia, Cay'enne, Valparaiso, Panama, Quito, Mendoza, Truxillo, Pernambuco, Carthagena, &c.

Where is Juan Fernandez, Terra del Fuego, Isle of Georgia, St Felix, Falkland Islands, Gallipago, Staten Land, &c.

Where are the Andes, Straits of Magalhaens, Lake Maracaybo, Cape Horn, Bay of All Saints, Cape St Roque, Gulf of Guayaquil, Cape Mary, &c.

Name the largest river in S. America, the principal river in the E. of Brazil, describe the Magdalena, name the three rivers which compose the Rio de la Plata; in what division are the rivers Essequibo, Demerara, Berbice, and Surinam; in what direction do these four rivers flow, where do they fall into, &c.

ON THE GLOBES.

I. ON THE TERRESTRIAL GLOBE.

1. THE artificial terrestrial globe represents the natural figure of the earth.

2. The axis is the rod or wire on which the globe revolves, and represents the imaginary line or axis about which the earth itself turns.

3. The poles of the earth or globe are the extreme points of the axis, in which it meets the surface one of them, the north or arctic; the other, the south or antarctic.

4. The circles on the globe are of two kinds, great and small (a). Every circle is divided into 360 degrees, or equal parts (b).

5. There are four great circles, viz. The equator or equinoctial line, the ecliptic, the meridian, and the horizon; and four small ones, viz. the arctic and antarctic circles, the tropics of Cancer and Capricorn.

6. The equator is a circle every where equally distant from the poles, and divides the globe into the northern and southern hemispheres (c).

7. The ecliptic is a circle which cuts the equator ob

(a) A great circle divides the globe into two equal parts; or it is a circle whose centre is the same with that of the globe. A small circle divides the globe into two unequal parts.

(5) Every circle, great or small, is supposed to be divided into 360 equal parts, called degrees; every degree is subdivided into 60 equal parts, called minutes; every minute into 60 equal parts, called seconds; every second into 60 equal parts, called thirds; and every third into 60 equal parts, called fourths, &c. Degrees, minutes, seconds, thirds, fourths, &c. are commonly denoted thus, 26° 14' 30" 25" 50"", &c.

(c) The latitudes of places are counted from the equator, northward and southward; and the longitudes of places are reckoned upon it eastward and

westward.

On most globes the degrees on the equator are marked from the meridian of Greenwich, with 10, 20, 30, &c. to 180° to the right hand, or E.; and, in like manner, towards the left hand from Greenwich, with 10, 20, 30, &c. to 180° W.; sometimes the degrees are marked the whole way round the globe to 360°. On the equator the 24 hours are also marked at equal distances of 15°: between the hours the minutes likewise are marked.

liquely at two opposite points, and represents the sun's path in the heavens. It is divided into 12 equal parts called signs, and each sign into 30 degrees. The names of the signs are Aries or the Ram, Taurus the Bull 8, Gemini the Twins п, Cancer the Crab,, Leo the Lion, Virgo the Virgin my, Libra the Balance ~, Scorpio the Scorpion m, Sagittarius the Archer ↑, Capricornus the Goat rs, Aquarius the Water-bearer, Pisces the Fishes ✈ (d).

8. The meridian of any place is a circle conceived to pass through that place, and through both the poles, dividing the globe into the eastern and western hemispheres. the brass ring which surrounds the globe is called the brazen meridian (e).

(d) It is called the ecliptic, because the eclipses must necessarily happen in this line, where the sun always is. The first six are called the northern signs, as they lie in the northern hemisphere, and the last six are the southern signs. The earth, in performing its annual revolution round the sun, advances 30 degrees every month in each of these signs, which causes the sun apparently to do the same in the opposite ones; thus, when the earth is in Libra, the sun appears to be in Aries, which is the opposite sign; when in Scorpio, we see the sun in Taurus; and so on through the rest. There is great reason to suppose, that the ancient astronomers affixed such images as those of the Ram, the Bull, &c. to the 12 signs of the zodiac as hieroglyphics of the seasons of the year, alluding to the annual course of the sun. Thus, Aries,* Taurus, and Gemini, represent March, April, and May, the spring quarter of the year, when lambs, calves, and goats (the latter generally bringing forth twin kids) are produced. Cancer, the Crab, which creeps both ways, represents the increase and decrease of the sun's declination, to and from the summer solstice in June. Leo, the Lion, intimates the raging heat of the sun in July, which the ancients compared to the furious nature of that fierce animal. Virgo, the Virgin, with a spike or ear of corn in her hand, properly represents August, when the harvest is ripe. Libra, the Balance, is displayed in September, to intimate that the days and nights, at the autumnal equinox, are equal in all parts of the globe. Scorpio, the Scorpion, a noxious animal, is placed as the hieroglyphic of October; because at that season diseases of various kinds were supposed to rage. Sagittarius, the Archer, marks November as the proper time for hunting. Capricornus, the Goat, by its climbing up the rocks, is placed as an emblem of December, when the sun, at the winter solstice, begins to ascend again towards the equinoctial. Aquarius, the Water-bearer, with his urn, represents January, when rains are fre quent. Pisces, the Fishes, are emblerns of the fishing season, which began in the Nile during the month of February.

(e) Every place upon the globe is supposed to have a meridian passing through it, though there be only 24 drawn upon the terrestrial globe; the

The sun enters Aries on the 20th or 21st of March, and the other signs nearly about the same day of the succeeding months.

9. The horizon is a great circle which separates the visible half of the heavens from the invisible; the earth being considered as a point in the centre of the sphere of the fixed stars. The horizon, when applied to the earth, is either sensible or rational. The sensible or visible horizon is the circle which bounds our view, where the sky appears to touch the earth or sea. The rational or true horizon is an imaginary plane, passing through the centre of the earth parallel to the sensible horizon; it determines the rising and setting of the sun, stars, and planets (ƒ).

deficiency is supplied by the brass meridian. They are called meridians, because when any of them is, by the motion of the earth, brought directly opposite to the sun, it is always mid-day or noon there. The brass meridian, like the equator and the ecliptic, is divided into 360°: but with this difference, that it is divided into 4 quadrants of 90° each. From the equa tor towards the N. and S. poles, the meridian is marked with a cipher over the equator thus (0), and on each side with 10, 20, 30, 40, 50, 60, 70, 80, and 90, ending at the pole. Then again from each pole to the equator on the other half of the meridian, is marked 10, 20, 30, 40, &c. to 90, which ends in the equator. The graduated edge of the brazen meridian shows the latitude of places, and their difference of latitude, either N. or S. from the equator. The distance of a place, E. or W. from the first meridian, or that of Greenwich, is called its longitude. The degrees of longitude are not equal, like those of latitude, but diminish as they approach the poles, as may be seen in the table of longitude, page 16.—Longitude may be converted into time, by allowing 15° to an hour; consequently every degree will answer to 4 minutes of time, and 15' of a degree will answer to one minute of time; and so on for the rest.

(f) The wooden horizon, circumscribing the artificial globe, represents the rational horizon on the real globe. This horizon is divided into several concentric circles, which on Cary's globes are arranged in the following order: The first, which marks the amplitude,* is numbered from the E towards the N. and S. from 0 to 90°, and from the W. towards the N. and S. in the same manner. The second contains the 32 points of the mariner's compass. The third contains the 12 signs of the zodiac, with the character of each sign. The fourth contains the degrees of the signs, each sign comprehending 30°. The fifth contains the days of the month answering to each degree of the sun's place in the ecliptic. The sixth contains the names of the 12 months in the year.-On these globes also, in the E. of the Pacific Ocean and W. from America, is a Table of Equation, showing the difference of time between the clock and the sun, likewise the declination

*The amplitude of any object in the heavens is an arc of the horizon, contained between the centre of the object when rising or setting, and the E. or W. points of the horizon. Or it is the distance which the sun or a star rises from the E. and sets from the W.; and is used to find the variation of the compass at sea.

N

10. The two tropics are situated parallel to the equator; one on each side, at about 23 degrees from it. The northern tropic is called the tropic of Cancer; the southern, the tropic of Capricorn; because they touch the ecliptic at the beginning of those signs (g).

11. The polar circles are situated at about 234 degrees from the poles; that on the N. is called the arctic circle, that on the S. the antarctic circle (h).

12. The horary or hour circle, is a brass ring surrounding the N. pole, having twice twelve hours marked upon it (i).

13. The quadrant of altitude is a narrow flexible plate of brass, equal to a fourth part of the equator, and divided into 90 degrees.

of the sun for every day in the year. The operation is performed thus: Bring the day of the month to the brazen meridian; and the particular minute of the scale of time, cut by the meridian, indicates how much the clock is too fast or too slow; the degree of the meridian which lies immediately over the day of the month the sun's declination for that day.

The two colures are two meridians, which pass through the poles of the world; one of them through the equinoctial points of Aries and Libra, and therefore called the equinoctial colure; the other through the solstitial points of Cancer and Capricorn, and therefore called the solstitial colure. These circles divide the surface of the globe into four equal parts, denoting the seasons of the year; thus, the equinoctial colure marks spring and autumn, and the solstitial colure marks summer and winter.

(9) The word tropic denotes a return, because in these points the sun returns again to the equinoctial line. These circles, the boundaries of the sun's apparent course, are usually marked on the globe by dots to distinguish them from other parallels which are drawn at the distance of 10 degrees from the equator and from each other. When the sun is over the tropic of Cancer, we have our longest day, the 21st or 22d of June, called the summer solstice; and when he is over the tropic of Capricorn we have our shortest day, the 21st or 22d of December, called the winter solstice ; when the sun is over the equator, it is equal day and night to all the world, the 20th or 21st of March and the 23d of September; the former of which we call the vernal equinox, the latter the autumnal equinox.

(h) As the north polar circle passes through the constellation called Arctos, or the Bear, it is thence called the arctic circle; and that which is opposite to it about the S. pole, is called the antarctic circle.

(i) On the best globes the horary circle is moveable; so that any hour upon it may be brought to the meridian; in others this is fixed, and has an index or hand, which may be turned to any hour.

The clock is too fast when the meridian cuts the western half of the scale of time, and too slow when it cuts the eastern half.