8. A MOUNTAIN is a part of land greatly elevated above the level of the surrounding country; as, Mount Blanc.

9. A COAST, or shore, is that part of a country which borders on the sea.

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10. The water is divided into oceans, seas, gulfs, bays, straits, estuaries, lakes, and rivers.

11. An OCEAN is a great collection of water, without any entire separation of its parts by land; as, the Atlantic Ocean.

12. A SEA is a smaller collection of water; as, the Baltic.

13. A GULF is a part of the sea running a considerable way into the land; as, the Gulf of Mexico.

14. A BAY is a part of the sea running a less way into the land, but more open at its entrance than a gulf; as, the Bay of Biscay.

The words, gulf and bay, are nearly synonymous, and seem in some cases to be arbitrarily imposed; as, the Bay of Bengal runs farther into the land than the Gulf of Guinea.' When a bay is very small, it is generally called a creek, and sometimes a harbour, station, or road.,.} anao) "Aur A 4% 15. A STRAIT is a narrow passage, by which two large bodies of water communicate with each other; as, the Strait of Gibraltar. 2778 fer p

16. An ESTUARY, OF FRITH, is the expansion of a river into an arm of the sea; as, the Frith of Forth. 17. A LAKE is a collection of water surrounded by ndas, the Lake of Geneva Polyra pa? #JÁME.

118. A RIVER is a large stream of inland fresh water; ast the Thamesimo, zrbaden - ul

GEOMETRICAL DEFINITIONS.

19. A CIRCLE is a plane figure contained by one line, called the circumference, which is every where equally distant from a point within it, called the centre.

Every circle is supposed to be divided into 360 equal parts, called degrees, each degree into 60 minutes, and each minute into 60 seconds. Degrees are marked with a small cipher, minutes with one dash, and seconds with two dashes. Thus, 23o 42′36′′, are read 23 degrees, 42 minutes, 36 seconds. A degree is only a relative idea, and not an absolute quantity, except when applied to a great circle of the earth, in which case it is 60 geographical, or 691 English miles nearly.

20. The RADIUS of a circle is a line drawn from the centre to the circumference.

21. The DIAMETER of a circle is a straight line drawn through the centre, and terminating at the circumference on both sides.

22. A SPHERE, or globe, is a perfectly round body, the middle point of which is called the centre.

23. A HEMISPHERE is the half of a sphere or globe, when divided by a plane passing through its centre. {

24. A GREAT CIRCLE divides the globe into two qual parts or hemispheres. L & T ARTE & 25. A LESS CIRCLE divides the globe into two unutte-di) to sinė alt. equal parts.

26. An ANGLE is the inclination or opening of two lines meeting in a point:^s : 308 903 to mus de câm 7570

27. When one straight line standing on another,

makes the angles on each side equal, each of these!

angles is called a RIGHT ANGLE; and the line which stands on the other, is called a PERPENDICULAR to it.

28. The TERRESTRIAL GLOBE is an artificial representation of the earth, with its several divisions of land and water.

29. The Axis of the earth is an imaginary line passing through its centre, round which it turns from west to east in twenty-four hours., of

Day and night are occasioned by the diurnal revolution of the earth upon its axis; and as this revolution is from west to east, the sun and stars appear r to move from east to west. 30. The POLES of the earth are the two ends of the axis, one of which is called the north and the other the south pole.

31. The EQUATOR is a great circle, supposed to be drawn round the earth at an equal distance from each pole, and divides the globe into two equal portions, called the northern and southern hemispheres. The equator, when referred to the heavens, is called the EQUINOCTIAL.

The equator, or equinoctial, is so called, because on the two days on which the sun is in the equator, the time of day and night is equal all over the world..

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32. The ECLIPTIC is a great circle, in which the sun makes his apparent annual motion among the fixed stars; or it is the real path of the earth round the sun. It is divided into twelve equal parts, called signs, which have received the following names from the constellations through which it passes :-"

Winter. Autumnal.

Summer. Spring.

Libra, or the Balancé, ....
Scorpio, or the Scorpion,

Sagittarius, or the Archer,..

Capricornus, or the Goat,................

Aquarius, or the Waterman, .............................
Pisces, or the Fishes, ......

The winter and spring signs are called ascending, and the summer and autumnal, descending signs.

The ecliptic is so called, because eclipses generally happen when the moon is either in or near this circle. Each of the 12 signs contains 30 degrees. The sun goes through one sign every month, and thus finishes his year in 365 days 5 hours and 49 minutes; the sun, therefore, moves through one degree nearly every day. There are four remarkable points in the ecliptic, called the two equinoctial and two solstitial points.March 21st is the vernal equinox, when the sun enters Aries, and spring begins; September 23d is the autumnal equinox, when the sun enters Libra, and autumn commences. On these two days the sun rises at 6 in the morning, and sets at 6 in the evening to all places upon the earth. June 21st is the summer solstice, or beginning of summer to the northern hemisphere, when the sun enters Cancer; this is the longest day to all places in the northern hemisphere, and the shortest to those in the southern. December 21st is the winter solstice,

or beginning of winter to the northern hemisphere, when the sun enters Capricorn; this is the shortest day to all places in the northern hemisphere, and the longest to those in the southern. The days increase continually to all places in the northern hemisphere, from the 21st of December to the 21st of June, and decrease from the 21st of June to the 21st of December; but in the southern hemisphere, the days increase from the 21st of June to the 21st of December, and decrease from the 21st of December to the 21st of June.

The ecliptic cuts the equator at an angle of 23° 28', which angle is called the obliquity of the ecliptic. It is this obliquity of the ecliptic that determines the distance of the tropics from the equator.

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33. The EQUINOCTIAL POINTS are the first points of Aries and Libra, where the ecliptic cuts the equator. 34. The SOLSTITIAL POINTS are the first points of Cancer and Capricorn, where the ecliptic is at the greatest distance from the equator.

35. The COLURES are two great circles passing through the equinoctial and solstitial points, and are hence called the equinoctial and solstitial colures.

36. MERIDIANS, or lines of longitude, are semicircles extending from the north to the south pole, and cutting the equator at right angles...

In every great circle passing through both poles there are two meridians exactly opposite to each other, and hence the one is called the opposite meridian to the other. The half which is in the opposite hemisphere, is sometimes called the (anti-meridian. Every place upon the globe is supposed to have a meridian passing though it; all places lying directly north and south of each other, are upon the same meridian. When the sun comes to the meridian of any place, it is noon or midday at that place. Meridian lines are generally drawn through every 10 or 15° on globes and maps of the world; but on