greater part of Asia Minor, extending also into Egypt, and doing much injury in Constantinople. At the latter city, the movement of the convulsion was observed to have a direction from east to west. On the 4th of December, of the same year, a violent eruption took place in Mount Vesuvius, two streams of lava, one of which was a mile in breadth, having burst forth, threatening destruction to the surrounding country.

On the 2nd of March, 1755, Etna was again in eruption, two streams of lava having poured from the highest crater, which was covered with snow, but which the fiery torrent suddenly dissolved, thus producing a frightful inundation. The convulsions in the more eastern part of this disturbed region, do not, however, appear to have wholly subsided; for, in the same month, the severe earthquake already alluded to as convulsing Mitylene, occurred in that island. Towards the end of this year, however, these tremendous disturbances approached the western confines of Europe and Africa. The convulsions swept across Sardinia and Corsica, agitated the greater part of Spain and the whole of Portugal, and, on the 1st of November, laid the city of Lisbon in ruins. The north-western parts of Africa, as we have already seen, were simultaneously convulsed; and, on the 19th of the same month, an earthquake proved terribly destructive in that region. The movement on this occasion was also from east to west; and is said to have travelled at the rate of twenty miles a minute.

After the terrible convulsion above mentioned, a longer pause appears to have ensued; but in July, 1757, the violent earthquake occurred, of which we have already given some description, as proving very destructive in the Azores; which appears to have terminated this remarkable series of disturbances: and which, it will be observed, traversed the tract we have mentioned, as forming the central line of the volcanic region, from the Caspian to the Azores.

The Icelandic volcanic region is a much less extended group, and may be considered as comprehending Iceland,

Jan Mayen's Island, and part of the coast of Greenland*. The latter is subject to earthquakes, and Jan Mayen's Island contains an active volcano, but Iceland constitutes by far the most important feature in this volcanic region.

Iceland, as far as has been observed, is wholly of igneous formation. It is subject to violent earthquakes, contains some of the most remarkable boiling springs in the world, and its volcanos are prodigiously active, and have been, at intervals, in violent activity from the earliest period of the discovery of this island. Among the volcanos of Iceland, Hecla appears to have been the most regular in its eruptions, and twenty-two formidable ones have been recorded, as occurring within the last eight hundred years; and, during the same period, twenty violent eruptions have taken place in the other Icelandic volcanos. So intense is the energy of subterranean heat in this cold region, that some eruptions of Hecla have lasted for six years without ceasing. Earthquakes also have shaken the whole island at once, causing great changes in the interior, rending mountains, causing hills to sink down, changing the courses of rivers, and forming lakes. New islands have also been thrown up off the coast, some of which have been permanent, but others have disappeared, either by subsidences, or by the action of the waves. An island of this description was formed in 1783, and was formally claimed by the King of Denmark, who conferred on it the name of Nyöe, or the New Island; but ere a year had elapsed, nothing was left, save a reef of rocks from five to thirty fathoms under water.

One of the most tremendous eruptions on record in Iceland, was that of the Skaptàr Yokul, which commenced on the 11th of June, 1783, and did not entirely cease for two

*From the continuous form observable in the outline of Greenland and the eastern shores of North America, and from the linear direction, bearing a general correspondence with the form of the coast, so frequently met with in volcanic regions, we should have been induced to place Canada in the Icelandic volcanic region; but we are not aware that any actual observations warrant this conclusion.

years. The immensity of the volume of melted matter ejected on this occasion, renders this eruption very remark able. Two streams of lava flowed in opposite directions, one of which extended fifty miles, and the other forty miles in length. The width of the first stream was about twelve or fifteen miles, that of the latter about seven; the ordinary height of both currents was about one hundred feet. The lava flowed into the deep channel of the River Skaptâ, and thus diverted it from its course; in consequence of which destructive floods ensued, which were greatly augmented by the melted snows that poured down from the mountain. The channel of the Skaptâ was between rocks, from 400 to 600 feet in depth, and nearly 200 in width; and not only did the lava fill up this great defile to the brink, but overflowed the adjacent fields to a considerable extent. The lava, after flowing for some days, was precipitated down a tremendous cataract, called Stapafoss, where it filled a profound abyss, which that great waterfall had been forming for ages. The loss of life and property was very great; twenty villages were destroyed, and above nine thousand persons perished, together with an immense number of cattle. The waters off the coast of Iceland, also, were so impregnated with the sulphureous exhalations, that the fish deserted the coast, a circumstance that added greatly to the distress of the inhabitants, who depend, in great measure, on the produce of the sea for their support. Iceland has scarcely to this day, recovered from the effects of this fearful calamity.

Beyond the limits of these volcanic regions, all countries are subject to slight tremors, at distant intervals of time. Slight shocks have frequently been felt in the British Isles, in France, Germany, and other parts of Northern Europe; but these countries cannot be considered as constituting parts of either the Southern European, or of the Icelandic, volcanic regions. In many instances, these tremors appear to be mere vibrations, produced mechanically, through the external crust of the globe, and originating

in some great convulsion in an adjoining volcanic region. Such were the agitations experienced in these islands, and over a considerable portion of Europe, during the great Lisbon earthquake. In other instances, however, these agitations appear to be independent of any such great convulsion. The year 1750 appears to have been marked by several commotions of the latter description, occurring in the countries of Europe, situated beyond the volcanic region. In the course of that year, a severe shock of an earthquake was felt at Munich, and in the surrounding country; numerous shocks were also experienced in France, particularly at Bordeaux, Toulouse, Narbonne, Montpelier, &c., though the shocks were most violent near the Pyrenees, where several houses were thrown down, and many persons killed.

In the same year, two smart shocks were felt in London and its vicinity. The first took place on the 8th of February, and was felt in all parts of the metropolis, as well as at Hampstead and Highgate, and along the banks of the Thames, from Greenwich to Richmond. It was particularly violent at Limehouse and Poplar, where, as well as in Leadenhall-street, some chimneys were thrown down; and, in several parts of the city, the pewter platters (then in use) fell from the shelves. The second shock occurred on the 8th of March, and was more violent, and of longer continuance, than the former. This took place at half-past five o'clock in the morning; and many persons quitted their beds, and ran into the streets in the greatest consternation. It, however, was attended with no loss of life, although several chimneys were thrown down, and some houses injured. It was particularly violent in the neighbourhood of Grosvenor-square, the copper and pewter utensils in the kitchens having been thrown off to some distance from the shelves. In St. James's Park, the ground is said to have heaved perceptibly. It extended to some distance round London, having been felt in parts of Kent, Surrey, and Hertfordshire. So great was the panic in the metropolis,

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that many persons, dreading a repetition of these convulsions, quitted London, shutting up their houses and shops, and seeking refuge in the country. No third shoek, however, appears to have occurred in the metropolis; but, during the same year, slight shocks were felt in various parts of England.

During the month of October, 1839, several shocks of earthquakes were felt in various parts of Scotland. Although not severe, they were sufficiently so to cause some alarm ; they occurred on the 7th, 10th, 13th, 14th, 16th, and 23rd days of October. The bells were set ringing; persons seated in chairs could with difficulty retain their seats, and stone dikes or walls were thrown down. But the most serious injury caused by this agitation of the earth, was the bursting of the Easeburn reservoir, on the banks of the River Carron, the waters of which swept over the adjacent lands, bearing every transportable article before them, and even rooting up young trees.

Compared, however, with the fearful effects of subterranean heat, displayed in the volcanic regions of the earth, these tremors appear of trifling importance; and although we may be ready to trust that, in the vast system of nature, these terrific convulsions may be beneficial, and that

Evil is partial; universal, good;

we cannot but feel thankful that our highly-favoured country is happily exempted from these appalling and destructive visitations.

But shouldst Thou wreck our father-land,

And mix it with the deep;

Safe in the hollow of Thy hand,

Thy little ones would sleep!