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To the north of Mexico, we meet with at least one active volcano, situated in north latitude 28°, in Lower California. Some accounts state that there are three, or even five volcanos in this region; but this territory is little known. As far, therefore, as our present information extends, this may be regarded as the termination, northwards, of the volcanic band in its full energy; though, as we shall presently find. some traces of volcanic activity extend further in that direction. Let us, however, now turn our attention to the volcanic area of the Caribbean Sea, and the adjacent shores.

The coast of Caraccas has, at various periods, suffered severely from earthquakes. Cumana was destroyed by an earthquake in 1796; and a similar catastrophe befell the city of Caraccas, on the 26th of March, 1812, when that city and seven other towns, were almost totally laid in ruins, and This terrible nearly twenty thousand persons perished.

convulsion extended to a great distance, for, besides violently agitating the whole of the Caraccas, a severe earthquake visited the island of St. Vincent, and convulsed the valley of the Mississippi for the length of three hundred miles. So violent was the agitation in the latter locality, that large lakes, twenty miles in diameter, were formed in the course of an hour, and others as rapidly drained; deep chasms yawned in the earth; and the ground on which the town of New Madrid is built, is said to have sunk eight feet below its former level.

The greater number of the West Indian Islands appear to be of volcanic origin, and there are active volcanos in St. Vincent's and Guadaloupe, as well as solfataras on some of the other islands. An eruption took place in the volcano of Morne Garou, in the island of St. Vincent, in April, 1812, at which time nearly all the plantations on the island were destroyed. Earthquakes of great violence are not unfrequent in these islands, particularly in a line extending from Jamaica to St. Domingo and Porto Rico. A severe earthquake occurred in St. Domingo in 1751, when the face of the island is described as having been quite altered;

mountains appearing where there were valleys; valleys where there were mountains; lakes where there were villages; and a new course being given to several rivers. Another severe convulsion occurred in the same island in 1770.

The volcanic region which we have now traced from the south of Chili, or perhaps from the island of Deception, to California and New Madrid, appears in South America to be chiefly confined to the western regions, no indications of volcanic disturbances having been observed in Guiana, Brazil, or Buenos Ayres. The remarkable volcanic formation near the River Santa Cruz, in Patagonia, is probably referable to a more ancient geological era*. In the eastern districts of North America, earthquakes are by no means of rare occurrence. We have already mentioned, that the valley of the Mississippi was convulsed at the period of the earthquake which destroyed Caraccas, in 1812; South Carolina, at the same time, was also much convulsed.

Springs of inflammable vapour have been discovered in several parts of North America. The village of Fredonia, in the state of New York, is lighted by a natural discharge of gas, which is collected by means of a pipe into a gasometer.

Earthquakes are very frequent on the shores of the St. Lawrence, often of sufficient violence to split walls and throw down chimneys. Such effects were experienced in December, 1791, at St. Paul's Bay, about fifty miles from Quebec.

These convulsions and indications of subterranean heat, appear, however, insignificant, in comparison with the stupendous volcanic forces we have been considering; nor can we regard them as a distinctly-marked continuation of

This remarkable volcanic formation consists of an immense stratum of lava, which forms a plain extending in every direction, and being about one thousand feet above the bed of the river; whilst, in some parts, black "Wonderful lava cliffs, and masses of basalt, rise like frowning castles. indeed," says Captain Fitz-Roy, "must have been the immense volcanie action, which spread liquid lava over such an immense tract of country!"

the vast volcanic band. Whether future researches may disclose its prolongation in the more western parts of North America, is still matter of uncertainty, but traces of more decided volcanic action have been observed in this portion of the continent. Thus, near the source of the Missouri, amid the snow-clad summits of the Rocky Mountains, two peaks are said to occur, which emit smoke in considerable volumes, apparently from volcanos in a state of eruption. Boiling springs are also met with in the same vicinity. Traces of volcanic action have likewise been noticed in the Spanish River Mountains, and other parts, lying between the Rocky Mountains and the Pacific; in which locality we also meet with the elevated volcanic cones of Mount Fairweather, fourteen thousand feet in height, and Mount St. Elias, sixteen thousand feet above the level of the sea. The two last-mentioned volcanos appear to be connected with the volcanic region of the Aleutian Isles, which, it will be remembered, form the northern commencement of the Asiatic volcanic region, and which thus appear to form a link, connecting the Old and New World.

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OCEANICA, under which appellation may be included Aus tralia, New Zealand, and the Polynesian Archipelago, forms another grand division of the globe.

The vast island of Australia, or New Holland, is about two thousand four hundred miles in length, and its width

varies from one thousand two hundred, to one thousand four hundred miles. This extensive tract of land does not appear to be traversed in its interior by any elevated mountain system; but, on the contrary, its principal mountain ranges border upon its shores, apparently encircling it on every side, and giving it, in this respect, some resemblance to Arabia and Persia. Finding that this region is possessed of this one natural feature in common with those territories, we shall be desirous of ascertaining whether any other similarity occurs; and upon inquiry we shall learn, that Australia, like Arabia and Persia, is remarkable for its deficiency of water; apparently not possessing any important river, and being, in some parts, subject to great droughts. The most characteristic feature of this region, however, appears to be the extensive lowland, which occupies so large a portion of the interior.

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The extreme south-eastern angle of Australia seems to enjoy a more agreeable climate than any other part of this vast island. Its greater distance from the equator gives it the advantage of a cooler temperature; to which the snowy mountains, called the Warragong Mountains, or Australian Alps, which are situated in this district, also contribute. Being, likewise, surrounded on three sides by the sea, it possesses an insular climate, and abundant supplies of rain. Extensive downs occur, covered with excellent pasture; and some districts of so fascinating a character," that Major Mitchell has bestowed on the country to the south of the River Murray the appellation of “Australia Felix." The hills are generally of a conical form, and the rocks of which they are composed consist almost wholly of lava; a circumstance to which the greater fertility of this region may perhaps in part be attributed. Mount Napier, situated between Portland Bay and the Grampian Mountains, contains a crater; the first hitherto discovered in Australia. This mountain is surrounded for several miles by a rock of volcanic formation.

The Grampian Mountains may be considered as the com

mencement of a mountain system, which, running nearly parallel with the eastern coast of Australia, extends to Cape York and Endeavour Bay. The highest summit in this range is Mount William, four thousand five hundred feet above the sea. In the parallel of Sydney, the range bears

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the name of the Blue Mountains. The mountains in this part do not appear to exceed three thousand feet in height, but, owing to the precipitous character of their surface, their more elevated parts are very difficult of access. Liverpool range, which branches off to the westward, is of totally different character, the summits of this range consisting of rounded hills, or flat plains, covered with grass. The Hardwick range takes a northerly direction, and some of the loftiest summits in Australia appear to be situated in this part. .

To the westward of this mountain system, a series of terraces occurs, which may be considered as the declivity of these mountains. These terraces consist of plains, of greater or less extent, separated from each other by low ridges; each ridge presenting a different geological formation. The terraces are destitute of timber trees, but are covered with luxuriant herbage, affording abundant food for cattle and sheep*.

Beyond the terraces, the lowlands commence, the extent of which is yet unknown. These plains are in many parts extremely level, though in others, they are slightly undulating; and they appear to have a gradual slope towards the south. In some districts, they are wholly destitute of vegetation; whilst, in others, saline plants occur, without an intervening blade of grass. Some of these plains are covered with polygonum, a gloomy and leafless bramble; and in others, as far as eye can reach, nothing is met with, except one kind of bush, forming a thick scrub. The richest soils in this part scarcely produce anything better than a small

*The greatest part of the wool exported from Sydney, and which is esteemed of superior quality, is furnished by the sheep of this district.

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