Islands are also divided into Continental or Oceanic, according as they lie near the large land-masses or far out at sea.

Definitions. The following terms are used to denote various portions of the land, according to their position relative to adjacent waters and degree of elevation.

(1.) According to position relative to adjacent waters :

Coast: The line where the land and water meet is called the coast.

That part of the land between high and low water mark is called the beach.

A Cape is a point of land advancing beyond the general coast-line, so as to project into the water.

Other terms such as Point, Head, Headland, and Promontory, are often applied to capes--the term point to low and the rest to lofty points of land. Local or special names, such as Ness, Naze, Mull, Bec, &c., are also applied to certain headlands.

A Peninsula is a portion of land nearly surrounded by water.

As the name implies, a peninsula is a part of the land which is "almost an island."
An Isthmus is a narrow neck of land uniting two larger portions.
(2.) According to degree of elevation :—

A Plain is a portion of land not much raised above the sea, and which has a more or less level surface.

Some of the great plains of the world are distinguished by special names, such as :

The Landes, or sandy plains of south-western France.

The Steppes of Russia and Central Asia, open and treeless plains.

The Tundras of Siberia, low swampy plains sloping into the Arctic Ocean.

The Savannahs and Prairies of North America.

The Llanos or grass flats periodically inundated by the Orinoco.

The Selvas or forest-plains of the Amazon valley.

The Pampas of La Plata, "broad thistly flats and grassy pastures."

A Tableland or Plateau is a tract of land rising to a considerable height above the sea.

A Hill is a mass of land rising from a few hundred to a thousand feet above the sea, while a Mountain is a mass of land rising considerably (as a thousand feet or upwards) above the level of the sea. Many such elevated masses lying close together form a Mountain-group, or, if in a line with each other, a Mountain-Range. Two or more mountain ranges, adjacent and on the whole parallel to each other, form a Mountain-chain, while a number of ranges and groups along the same axis of elevation forms a Mountain System.

Small hills are variously named. The general term is Hillocks, but if rounded they are called Knolls, if of chalk formation and rounded, Downs. Sand-hills on the sea-shore are called Dunes. High prominent peaks are in some parts of England called Tors, or, if formerly used as fire-signal stations, Beacons.

A narrow opening between two adjoining mountains is called a Mountain Pass, and also, in some cases, a Defile or Ravine. The passes over mountain-chains lie, in some instances, at vast heights above the plains below.

A Volcano is generally a conical elevation with a cup-like hollow at its summit called a Crater, from which lava, mud, &c., are ejected.

Volcanic districts are especially subject to Earthquakes. The Geysers of Iceland throw out jets of hot water; the Solfataras of Italy, &c., emit sulphur and other gases.

Valley. A sloping portion of land, bounded on either side by lands of greater height, forms a Valley.

The forms, both of valleys and of hills, are infinitely varied. Sometimes the slopes are long and gentle. In other cases they are abrupt and steep, so that the valley passes gradually into a ravine or defile. Valleys are generally named after the rivers which flow through them, as the Valley of the Nile. In Scotland, the terms Strath, Carse, Dale, &c., are used, as Strathmore, &c.

A tract of country which does not allow of sufficient cultivation to be fit for the settled abode of man, is called a Desert.

The vast region called the Sahara, in Africa, is the most prominent example. It is to the want of water that the sterility of such tracts is for the most part due. But even in the Sahara there are, here and there, a few fertile spots, called Oases.

Natural Divisions of Water: The terms applied to the various portions or natural divisions of the waters of the globe are the following:

Ocean. The vast expanse of water which covers the larger portion of the earth's surface is called the Ocean.

The Ocean is divided by the intervening lands into three great basins-the Pacific, Atlantic, and Indian Oceans. The waters which lie around the North Pole are, in addition, distinguished as the Arctic Ocean, and those around the South Pole are called the Antarctic Ocean.

None of the three great oceans has, properly speaking, any defined limit to the southward. Their waters communicate, without interruption from land, in that direction. The Antarctic Circle is assigned, for geographical convenience, as their common line of division from the waters that lie around the South Pole. A line drawn from Cape Horn to the Antarctic Circle is, for a like reason, assigned as the common limit between the waters of the southern Pacific and the southern Atlantic basins. A similar line drawn from Cape Agulhas southwards indicates the boundary between the south Atlantic and Indian Oceans, and the meridian which passes through the southernmost headland of Tasmania is regarded as the limit between the basins of the Indian Ocean and the southern Pacific. But these lines have no place in nature, and the term Southern Ocean is commonly applied to the belt of sea which extends (with little interruption from land) round the globe between the parallel of 35 S. Lat. and the Antarctic Circle. The sea which washes the southern shores of Australia is thus spoken of as the Southern Ocean.

Sea. The word sea is sometimes used as an equivalent for ocean, but is more generally applied to less extensive portions of the water, situated near the land. A sea which pene. trates within the land, so as to be nearly enclosed by it, is called an Inland Sea.

Inlets, or indentations of the coast-line, are variously named according to their form and size.

A Bay is a short arm of the sea indenting the land. A Bight is an open bend in the line of coast. A Gulf is a longer arm of the sea, penetrating farther into the land.

Smaller openings or inlets, sufficiently deep and sheltered for vessels to lie in safety, and discharge and receive their cargoes, are called Havens, Harbours, or Ports. A Creek or Cove is a small opening in the coast. A Firth, Fiord, or Fjord, is a narrow inlet, as the Firth of Tay, the Sogne Fjord. An Estuary is an inlet forming the mouth of a tidal river, as the Estuary of the Thames.

The portions of water connecting larger expanses are called Straits, Channels, or Sounds.

A Strait is a narrow arm of the sea connecting two larger portions. A Channel is a broader arm of the sea. A Sound is a narrow arm of the sea between an island and the mainland.

Lake. A lake is a body of inland water surrounded by land.

Small lakes often occur in mountainous countries, their beds consisting of hollows or depressions in the land, in which the running waters have accumulated.

be thus classified :

(1.) Lakes which receive rivers, but have no outlet.

(2.) Lakes which do not receive any rivers, but have an cutlet.

(3.) Lakes which both receive and emit rivers.

(4.) Lakes which receive no rivers, and have no outlet.

Lakes may

A Pond is a small body of fresh water, and has no outlet. A Lagoon is a shallow lake of salt water near the sea. In Scotland and Ireland respectively, the words Loch and Lough are used instead of Lake. In England, a small lake is often called a Mere.

River. A river is a stream of water running through the land, and generally rises in high ground, and discharges its waters into the sea, sometimes passing through one or more lakes on its way.

Almost every place has in its neighbourhood examples of small running streams or brooks: the junction of several such brooks, so that their waters become united in a larger channel or water-course, forms a river. The Thames, the Severn, and the Shannon, in our own islands, are among the most prominent examples of rivers; the Danube and the Volga, on the continent of Europe, are instances on a larger scale.

The Source of a river is where it begins.

The Mouth of a river is where it ends.

The Bed of a river is the hollow along which it flows.

The Banks of a river are the margins of land between which it flows; that on the righthand side (following the course of the stream) is called the right bank, that on the left, the left bank.

The Length of a river is the distance between its source and its mouth.

The Width of a river is the distance between its banks.

The Basin of a river is the whole tract of country which is drained by it and its tributaries. Thus we say (in Physical Geography), the Basin of the Thames, the Basin of the Danube, meaning thereby the whole district through which those streams, with all their affluents, respectively flow.

A Tributary or an Affluent is a small stream which joins a larger river. Thus the small river Kennet, in Berkshire, is an affluent of the Thames; and the river Inn is an affluent of the Danube.

When a large river flows over a precipice it forms a Cataract. The fall of a small river forms a Cascade. When the slope of the bed of a ver is steep or uneven, a Rapid

is formed. An artificial water-course is called a Canal.

Water-shed. A water-shed or, more correctly, "water-parting," is the ground which divides adjacent streams that flow in opposite directions.

This generally (but by no means always) consists of a high tract of land, sometimes of a chain of mountains; and it is, in every case, formed by ground which is higher than that through which the streams actually flow, for the natural tendency of water is to run down a sloping ground, from a higher to a lower level. Some rivers, however, rise in ground which is nearly level, and at only a trifling height above the sea; in such cases, the water-shed may consist of ground which does not exhibit any marked elevation above the adjoining plain.

The Distribution of Land and Water over the earth's surface is extremely irregular, most of the land being north and most of the water south of the equator.

The areas (in square miles) of the land and water in the various hemispheres into which the globe may be divided are estimated as follows:

Distribution of Land: The Northern Hemisphere thus contains three times as much land as the Southern, and there is in the Eastern Hemisphere twice as much land as in the Western, while the Continental Hemisphere contains five-and-a-half times as much land as the Oceanic half of the globe.

Distribution of Water: The above Table also shows that the Southern Hemisphere contains nearly half again as much water as the Northern, and the Western Hemisphere a third more than the Eastern, while the Oceanic Hemisphere includes fully three-fifths of the entire water-area, while there is only one-third of it in the Continental Hemisphere.

Distribution of Land and Water in Zones: The areas (in square miles) of the land and water in each Zone have been estimated at :

In the North Temperate Zone, land and water are almost exactly equal in area, while in the South Temperate Zone there is 11 times as much water as land. The Torrid Zone has three times more water than land, while the two Temperate Zones together include three-fifths of the entire land area of the globe.

The most habitable portions of the earth, i.e., the two Temperate Zones, have thus the largest land-area; the Torrid Zone, so unfavourable to the development of industry and energy, has a limited land-area, but a vast expanse of water; while the Frigid Zones, the one nearly and the other entirely uninhabitable, are the least extensive of all the zones, their united areas amounting to only,th. of the total area of the globe.

Contour of the Land: The contour or coast-line is the line of contact between the land and the sea.

This line is practically the same everywhere, and, excluding the variations caused by winds and the tides, uniformly level, and its mean height between high and low water is adopted as the basis of measurement of elevation on land and depth at sea. This basis or Sea-level is thus the general elevation of the surface of the sea, and is supposed to correspond with the mean level of the earth as part of its circumference.1 A comparatively slight change of sea-level would alter very considerably the present outline or configuration of the land.

If the sea-level were depressed 100 fathoms, or alath, part of the distance from the earth's centre, Great Britain would form part of the Continent of

1. This is not strictly true. As a matter of fact. the belt of water bordering on the land is attracted by it, and especially if along or near its margin there are great elevated masses such as the Andes and the Tulayas. The attraction of the latter, for

instance, causes the level of the Bay of Bengal to be some 30 feet logher than the level of the sea at Ceylon, and it is a well-known fact that the sea-level on the Pacific shore of the Isthmus of Panama is higher thin on the Atlantic side.

Europe; the beds of the North Sea, the Baltic, and the Black Sea would be dry land; New York would lie a hundred miles from the coast; and the southern end of Newfoundland would be east of the then inland city of Boston."

If the sea-level were elevated 100 fathoms, "London, Paris, New York, in fact every large city in the world, would be submerged, along with nearly half of America, three-fourths of Europe, a third of Asia, and half of South America and Australia."

Contrasts and Similarities.-If we compare the contours, or outlines, of the great land-masses, we at once discover some rema: kable contrasts and similarities.

An inspection of the map of any country shows that the contour or coast-line is nowhere an absolutely straight line, but, with one or two exceptions, the coasts of all countries are irregular lines, constantly varying in form and direction. Some coasts, like the eastern coast of England, present a succession of flowing curves; others, like the Norwegian coast, are deeply indented by innumerable inlets.

An inspection of a map of the world shows that the common form of the land, both in the mass and outlying portions of it, is that of an irregular triangle, with its base to the north and its apex to the south. Thus the Continents of North and South America and Africa are roughly triangular in form, tapering towards the south, as also are nearly all the great peninsulas of the world, e.g., India, California, the Balkan Peninsula, &c.

Development of Coast-line: The more varied the outline of a country or continent, the greater the extent of coast-line in proportion to its area.

Each mass of land consists of the trunk or main body, and the limbs (ie., peninsulas, headlands, &c.). If, then, a series of geometrical figures be drawn approximating to the general shape or outline of the continental land-masses, it will be seen that the number and comparative extent of the projecting limbs' differ very considerably, and that while Europe has a greater number of 'limbs' than any other continent, Africa and Australia have fewer, both relatively and absolutely, than Europe, Asia, or America. This difference in development of coast-line is attended with the most important results, for the more irregular the coast-line of a country or continent is, the greater the facilities for

Commercial Intercourse, and the higher, generally speaking, the civilization. And, conversely, the fewer projections or limbs a country or a continent has, the lower its civilization. Compare in this respect Europe and Africa. The vast improvement in the means of communication is, however, rapidly surmounting natural obstacles to free intercourse with hitherto isolated and backward countries.

Similarities: The most striking similarities in form or contour of the great land-masses, are :—

(1) The Eastern and Western Continents, alike, decrease in width from north to south.1 (2) The western sides of the continents of Africa and South America have each a deep bend or incurve, and a corresponding projection or outcurve on the eastern side.2

1. Lord Bacon first pointed out how the southern extremities of the Old and the New World, terainate in points turned towards the south, while they widen towards the north. This is true also of the rest peninsulas of heard.

2. In Australia, the incurve (the Great 13 ght is on the south side, and the corresponding outcurve the Northern Territory of South Australia) on the north.