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A GENERAL

TEXT-BOOK ON GEOGRAPHY.

[The preceding part of this work, which treats of Geography as a science, is intended for the use of TEACHERS and their MORE ADVANCED PUPILS. The part which follows may be divided into Two COURSES, one for BEGINNERS,a as Definitions, General Divisions, and those portions of the text which are printed in larger type; and the other, or SECOND COURSE, will serve as a general TEXT-BOOK on the subject of Geography.]

PRELIMINARY DEFINITIONS.

GEOGRAPHY is a description of the EARTH. See pages 15 and 16. The form or shape of the earth is round like a ball or GLOBE. The CIRCUMFERENCE of the earth or a circle which would divide it into two equal parts or hemispheres, is nearly 25,000 miles.

The DIAMETER of the earth, or a straight line from any point of its surface through the centre to the opposite point, is nearly 8,000 miles. See page 45.

The AXIS of the earth is an imaginary line passing through its centre from north to south. The ends or extreme points of the earth's axis are called the POLES; the upper the north pole, and the lower the south pole.

It

The earth turns round its axis once in twenty-four hours, producing DAY and NIGHT, alternately. This is called its DIURNAL motion. also moves round the sun in the course of a year, producing the SEASONS in succession. This is called its ANNUAL motion. See page 26 for proofs and illustrations.

The EQUATOR is an imaginary circle passing round the middle of

See "Method of Teaching Geography," page.

the earth, at an equal distance from each pole. It divides the earth into two equal parts, which are called the northern and southern

HEMISPHERES.

LATITUDE is the distance of a place north or south from the equator. See page 47.

PARALLELS OF LATITUDE are circles drawn round the globe parallel to the equator.

The most important parallels of latitude are the two TROPICS," and the two POLAR circles.

The tropics and the polar circles divide the globe into five ZONES or belts; namely, one torrid, two temperate, and two frigid zones. See the diagram, page 46.

The TORRID Zone lies between the tropics; the TEMPERATE zones between the tropics and the polar circles; and the FRIGID zones between the polar circles and the poles.

A MERIDIAN is an imaginary line running through any place north and south from pole to pole.

The meridian which passes through Greenwich is called the FIRST

MERIDIAN.

LONGITUDE is the angular distance of the meridian of a place east or west from the first meridian. See page 48.

The circle which crosses the equator obliquely is called the ECLIPTIC. The ecliptic marks the line along which the sun's rays are vertical or overhead, in the course of the year.*

The sun is never vertical or overhead to any place on the earth farther from the equator than 23 degrees north and south, through which limits the tropics are supposed to be drawn; Cancer to the north, and Capricorn to the south. These parallels are called tropics, because when, by the motion of the earth, the sun arrives at either of them, he turns back, as it were, towards the other. Before turning back, he apparently rests or attains the same elevation for two or three days. These periods are called the summer and winter SOLSTICES, that is, the standing or resting of the sun.

When the sun is 23 degrees south of the equator, that is, in the tropic of Capricorn, his rays fall short of the North Pole by the same number of degrees (234). Through this point, a circle parallel to the equator is supposed to be drawn, which is called the Arctic, or North Polar Circle; and through the corresponding point in the southern hemisphere a similar circle is supposed to be drawn, which is called the Antarctic, or South Polar Circle. The North Polar Circle is called Arctic, in allusion to its corresponding circle in the heavens, which passes through the constellation ARCTOs, or the Great Bear; and Antarctic means opposite to the Arctic.

Such a line is evidently a semicircle, and if carried round the whole globe, a circle. See pages 46 and 49.

d In the vicinity of London, where the Royal Observatory is.

The ecliptic properly refers to the heavens, and represents the circle which the sun, by the earth's annually revolving round it, seems to

The ZENITH is that point in the heavens which is directly over the head of the observer.

The NADIR is the point directly opposite to the zenith.

The SENSIBLE HORIZON is the circle bounding the view of the olserver by the apparent meeting of the earth and sky.

The RATIONAL HORIZON is a great circle whose PLANE passes through the centre of the earth parallel to the plane of the sensible horizon.

The CARDINAL, or four principal points of the horizon, are the NORTH, SOUTH, EAST, and WEST. See page 7.

NATURAL DIVISIONS OF THE EARTH'S SURFACE. The surface of the earth consists of land and water. The water covers nearly three-fourths of the earth's surface. See page 11.

The principal subdivisions of the LAND are, continents, islands, peninsulas, capes, promontories, and isthmuses; and of the WATER, oceans, seas, gulfs, bays, channels, straits, and lakes.

DIVISIONS OF THE LAND.

A

A CONTINENT is a large extent of land containing several countries. An ISLAND is a portion of land entirely surrounded by water. A PENINSULA is a portion of land almost surrounded by water. CAPE or headland runs out into the sea; and if elevated or mountainous, it is called a PROMONTORY. An ISTHMUS is a narrow neck of land, connecting two larger portions together.

A TABLE-LAND or PLATEAU (platõ) is a plain or tract of flat land elevated considerably above the level of the sea. An OASIS is a fertile spot in the midst of desert. A WATERSHED is the ridge or boundary

describe among the fixed stars in the course of the year. The sun is always in the ecliptic, and hence, when the moon comes in a line between us and the sun, his rays are partially eclipsed or obscured. This is called an eclipse of the sun, and it is from this circumstance that the sun's apparent path in the heavens is called the ecliptic. See page 35.

The rational horizon is the circle which separates the visible hemisphere of the heavens from that which is not visible. The broad wooden circle on a terrestrial globe represents the rational horizon.

The learner should be required to point out, on the Map of the World, examples of each of the divisions of land and water.

Isthmus.-The human neck, head, and body will serve to illustrate the geographical terms isthmus, peninsula, and mainland. In fact, isthmos, in Greek, from which the word is derived, means the neck. By curving or holding out one of his arms less or more from his body, tl e teacher can illustrate what is meant in geography by arms of the sea, gulfs, bays, creeks, and harbours.

line which separates two neighbouring river basins. The BASIN of a river is the whole extent of a country drained by it, and its affluents or tributaries. A DELTA is a triangular tract of land between the forked mouths or branches of a river.

DIVISIONS OF THE WATER.'

An OCEAN is a large extent of water, corresponding to a continent. A SEA is smaller than an ocean, and is generally bounded or confined by land. A GULF corresponds to a peninsula, and is almost surrounded by land. A BAY has a wider opening than a gulf, and is, generally speaking, not so large. A SEA containing a cluster of islands is called an ARCHIPELAGO. A STRAIT is a narrow passage of water connecting two seas: it corresponds to an isthmus. A CHANNEL differs from a strait, in being much wider. A CREEK is a narrow portion of water running up into the land. A HARBOUR or HAVEN is a part of the sea so nearly surrounded by land as to afford complete security for ships. A ROAD or ROADSTEAD affords safe anchorage near the land, with partial shelter. The mouth of a river widening into the sea, is called an ESTUARY or FIRTH. A LAKES is a portion of water entirely surrounded by land: it corresponds to an island. An ARTIFICIAL GLOBE is a representation of the form of the earth, with its divisions into land and water.

A MAP is a representation of the earth, or of a part of it, on a plane surface. See page 9.

The top of the map is the north; the bottom, the south; the righthand side, the east; and the left-hand side, the west. In a map of the world, longitude is marked on the equator, and latitude on the circles that contain the two hemispheres. But in maps of particular countries, longitude is marked at the top and bottom, and latitude at the sides. The lines running from the top to the bottom of the map, that is, north and south, are MERIDIANS; and the lines which run from one side of the map to the other, that is, east and west, are PARALLELS. diagram, p. 46.

d

GRAND OR GENERAL DIVISIONS OF LAND AND WATER.

See the

Of the land on the earth's surface there are FIVE GREAT DIVISIONS, namely, Europe, Asia, Africa, America, and Oceania, which includes Australasia, Melanesia, Malaysia, Micronesia, and Polynesia. Europe, Asia, and Africa are sometimes called the Old

Delta.-This is the name of the Greek letter D, the shape of which is triangular (A).

b So called with reference to the Archipelago.

с

Lake.-Large lakes in Ireland are called loughs, and in Scotland, lochs; as Lough Neagh, Lough Erne; Loch Katrine, Loch Leven. These terms are also applied to arms of the sea; as the Lough of Belfast, Lough Foyle, &c.

4 See page 12 for estimates of the extent of each of the great divisions of land.

World, and sometimes the Eastern Continent; while America is generally called the New World, or the Western Continent.

and

Of the water on the earth's surface there are also FIVE GREAT DIVISIONS, namely, the Pacific, Atlantic, Indian, Arctic, Antarctic oceans."

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The Pacific Ocean extends from the western shores of North and South America to the eastern coasts of Asia and Australia.

By looking on a map of the world, it will be evident that all these oceans communicate with each other, and that, strictly speaking, there is but one ocean or vast body of water which extends over nearly threefourths of the earth's surface. Of these great divisions of water the Pacific is the largest, being about 8,000 miles from north to south, and 11,000 from east to west. The Atlantic is next in extent, being about 9,000 miles from north to south, and where broadest, from east to west, between 3,000 and 4,000 miles. The Indian Ocean is about 6,000 miles from north to south, and about 5,000 miles from east to west.

The Pacific was so called because it was erroneously supposed, when first discovered, to be free from storms; and contrasted with the Straits of Magellan and the adjoining seas, it well deserves its name. The Atlantic takes its name from Mount Atlas on the western coast of Africa; and the Indian Ocean, from India or Hindostan. The Arctic means the north, and the Antarctic opposite to the north.

As the bottom of the sea is doubtless like the surface of the earth (which was at a former period in the same position), it might be

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