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on the banks of the Nunez. But though so few traces of igneous action occur on the mainland, nearly all the African islands are of volcanic origin, and many of them contain active volcanos, and also suffer from earthquakes.

On the north-eastern side of Africa, a small volcanic group occurs; Jebel Teir, an island in the Red Sea, being an extinct volcano; whilst another, in a state of activity, is said to exist on the adjacent shores of Arabia; and in the south of Abyssinia, many indications of volcanic agency have been observed. Thus, (according to the recent accounts of Mr. Isenberg,) the ground near Muja is full of chasms and gulfs, the remains of volcanos; the mountains south of Karanta are also volcanic; ashes are met with in the adjacent valleys; and the elevated plain of Arabdera is covered with volcanic stones. The principal group, however, on the eastern side of Africa, is that which includes Madagascar, and the islands of Mauritius and Bourbon. Madagascar contains an active volcano, to which the appellation of Radama has been given, in honour of the late enlightened chief of that name. Mauritius is volcanic; and Bourbon consists entirely of a mass of volcanic matter, forming two mountains, one containing an active volcano, which, for a long period, has regularly emitted lava on alternate years. This island also presents many indications of violent convulsive movements".

On the western side of Africa, the rather distant island of Tristan d'Acanhua, (which rises abruptly from the sea, in the form of a truncated cone,) consists of an extinct volcano. St. Helena is also wholly of volcanic formation, and subject to earthquakes. The island of Ascension is chiefly of similar composition, and vast beds of scoriæ and lava cover many parts of the island. Approaching nearer the mainland, we meet with the Isles de Los, which consist of a series of volcanic islands, some forming, and others diminishing in size. Of similar formation are the islands in the Bight of

The volcanic island of Amsterdam is too far removed to be included inthis group.

Biafra, including Anna Bom and Prince's Island, the latter of which was so named from

The Lusitanian Prince*, who, Heaven inspired,

To love of useful glory roused mankind,

And in unbounded commerce mixed the world.

Proceeding northwards, we find the Cape Verde Islands, not only volcanic, but containing, besides many other indications of energetic igneous agency, an active volcano in the island of Fogo, which, from the ashes which fell on a vessel, appears to have been in eruption in February, 1839. The whole group of the Canaries is volcanic; and in some parts of these beautiful islands, splendid basaltic cliffs rise perpendicularly from the sea to the height of 1500 or 2000 feet, whilst the peak of Teneriffe attains the elevation of 12,236 feet. The crater at the summit of this cone has, since it has been known to modern Europeans, ceased to emit lava, but is in the state of a solfatara †; and numerous eruptions have taken place from lateral openings in the mountain. And though no very recent eruptions appear to have occurred in the other islands, one of most terrific description took place in Lancerote, which commenced in 1730, and lasted for above five years. The island of Madeira consists of one mass of basalt, and has also frequently suffered severely from earthquakes. It may, however, be questioned, whether both this and the Canaries, ought not rather to be included in the European volcanic region; unless indeed we may consider them as links, uniting the African and European volcanic chains.

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Henry, third son of John the First, king of Portugal, whose enterprising spirit greatly conduced to the improvement of modern navigation. He flourished in the beginning of the fifteenth century.

+ A volcanic vent, from which sulphur, or sulphureous, watery, and acid vapours and gases, are emitted, but which does not emit lava, or other solid products, is termed a solfatara.

317

CHAPTER XIX.

THE NEW WORLD.-GENERAL FEATURES OF NORTH AMERICA. -NORTH AMERICAN ISLANDS.

Say, who first passed the portals of the West,
And the great secret of the deep possessed:
Who first the standard of his faith unfurled
On the dread confines of an unknown world.

By Heaven designed

To lift the veil that covered half mankind!-ROGERS.

THE form of the New World offers a strong contrast to that of the Old World, and instead of consisting of a vast extension from east to west, stretches from north to south, through 120 degrees of latitude. The principal range of mountains corresponds with the form of the continent, traversing it throughout its whole extent, and presenting by far the most continuous line of elevated land, on the surface of the globe; the length of this mighty range, in some parts containing summits of stupendous elevation, being little less than nine thousand miles.

The continent of America may be divided into three grand portions, North America, South America, and Central America.

One of the most important and striking features of North America, consists of the vast range of mountains, forming part of the grand central axis of the New World. These mountains were known to the early settlers as the Chippewayan Mountains; but from their broken and rugged character, and bare granite summits, they have received the name of the Rocky Mountains, or the Stony Mountains. This range runs parallel to the shores of the Pacific, from the Isthmus of Panama to the borders of the Arctic Ocean, where it terminates at no great distance from the mouth of Mackenzie's River. Many of the summits attain a considerable elevation, ranging from 12,000 to 15,000 feet. The

altitude of these mountains does not, however, appear to have been very correctly determined; and it has even been stated, that the elevation of one peak approaches to 25,000 feet above the level of the sea, and that others, little inferior in height, occur in the same vicinity. This, however, perhaps requires confirmation. The Rocky Mountains, especially in their northern prolongation, are divided into several parallel ranges; and in one part, no less than thirteen successive ridges are said to occur. These ridges are in some places intersected by elevated table-lands, and in others by deep and well-watered valleys; but the peaks of the mountains are generally bleak and bare; and in their higher parts covered with perpetual snow. These snowcapped summits present a brilliant appearance, from whence these mountains obtained, among some of the first observers, the appellation of the Shining Mountains.

The other principal mountain ranges of North America, also take a general direction from north to south. Between the Rocky Mountains and the Pacific, a mountain range, in some parts connected with the central line, with which it runs nearly parallel, extends from the northern parts of the continent to the peninsula of Lower California, where it bears the name of the Californian Maritime Alps. The River Colombia, which takes its rise among the rugged summits of the Rocky Mountains, crosses this secondary range, where it forms some grand cataracts, and having passed between the lofty summits of Mount Hood and Mount St. Helens, pours its waters into the Pacific, after a course of a thousand miles.

In the eastern parts of North America, the Alleghany or Apalachian Mountains also extend from north to south stretching from Alabama and the northern confines of Georgia, nearly to the banks of the St. Lawrence. These mountains are by no means so elevated as those of Western North America, the highest summits not much exceeding 6000 feet; and the general elevation of the Alleghanies ranges from 2000 to 3000 feet above the level of the sea.

The Lowlands of America form another striking feature in its natural geography. These extensive levels generally possess a sandy soil, and in some parts bear much resemblance to the steppes of Asia. They are naturally divided into three portions; namely, the Western Lowland, or the plains between the Rocky Mountains and the Pacific; the Central Lowland, comprising the vast plains through which the Mississippi flows; and the Eastern Lowland, consisting of the comparatively narrow plains lying between the Alleghanies and the Atlantic.

The north-western portion of the Western Lowland has been but little explored; as far, however, as it is known, it appears to contain vast plains, which are nearly destitute of trees; widely differing in that respect from this region in lower latitudes, where, however, it assumes a less level character, and where a great extent of country is covered by vast forests of most magnificent fir trees, including the valuable and gigantic Douglas pine*, the trunks of which vary in diameter from two to ten feet, and in height from 100 to 180 feet. Upper California possesses both a delightful climate and a fertile soil, but between that territory and the Rocky Mountains, a great sand plain occurs, 700 miles in length, and varying in width from 100 to 200 miles. The peninsula of Lower California possesses generally an arid soil, and the land capable of cultivation is very limited in extent; but it is noted for enjoying the most beautifully clear sky in the world.

The whole of North Western America possesses a milder climate than the central or eastern districts of the same continent, the winters being less severe, and the summers more temperate, than in the latter districts; a particular instance of which has been already mentioned, in speaking

This important species, which has only been known within a recent period, having been discovered by Mr. Douglas, appears likely to be successfully introduced into this country, the climate of which seems to suit it perfectly. Its growth is very rapid.

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