In Silesia, at Adersbach, is an extraordinary labyrinth of rocks, four leagues in length, and two in breadth. These rocks are entirely composed of sandstone, and at first sight they look like a city of gigantic architecture in ruins, for we can literally walk through the interior of the labyrinth "as we would in the squares and streets of a town, and it hardly requires a stretch of the imagination to say that we see dismantled towers, triumphal arches, dilapidated fortifications, &c. Tradition has baptized many of these masses of rock with the most fanciful appellations: here we have the statues of burgomasters and soldiers, there friars and nuns, and in another place the emperor's throne. One of the loftiest of these rocks, termed the watchtower, is, I should think, between 400 and 500 feet high, but its circumference is not more than that of the object from which it borrows its appellation. Another of nearly equal altitude, which goes under the name of the Zuckerhut (sugar-loaf), is, in form, an inverted cone, and being isolated, and at some distance from all the rest, has a most singular appearance."
At Golling, in the Tyrol, the river Salza forces its passage through ravines and mountain defiles. In one place, "the stream has perforated the rock in its descent, and falls in a sort of curtain over the lower part of it into the channel at the foot. Over these falls, and about half-way up the mountains, there is a splendid arch or natural bridge."
At Virginia in North America, over a small stream, in the upper part of the great Valley of Shenandoah, is a splendid natural curiosity, called the Rock Bridge. "It is a noble arch of one solid mass of stone, somewhat curved in its highest part, and almost like the work of man. The same native rock forms on each side the supports of this enormous arch, which is said to be about eighty feet wide near the top; at the level of the water the width is only forty feet. The whole height from the outer top of the arch to the water, is about 210 feet, as ascertained by admeasurement with a string and a stone at the end; the vertical thickness of the arch is probably about thirty-feet. The stream which runs beneath, though inconsiderable, adds to the general effect. Drops of water filter through the limestone, and fall in quick succession from the arch, and, by the time occupied in their descent, their increasing velocity, and their full bright appearance, serve in some degree to give a measure of the height from which they fall, and increase the beauty of the scene." There is another natural bridge in Virginia, in Scott county, which is said to be above 340 feet high.
Mr. Fortune, in his Wanderings in the Northern Provinces of China, mentions that he met with "some immense blocks of stone (granite), supported naturally on the tops of the hills in the strangest manner, which are objects of great interest to the traveller. One, in particular, appears as if some giant arm had raised it to its present position, and left it there solely to astonish the beholder in after ages, and leave him to wonder not only how it came there, but how it could remain in its present position, and, most assuredly, a very small quantity of gunpowder exploded below it, would hurl it from the hill into the plain beneath."
SAND HILLS IN SOUTH AUSTRALIA.
Mr. Angas describes the sand hills or drives near the river Coorong in South Australia as being of immense height, and presenting the appearance of barren mountains. In one place, he says, there is "a vast chasm, resembling an extinct crater, which rent these sandy heights, surrounded by masses of sandstone and projecting rocks. In every direction were seen hollow tubes of sand, cemented by moisture and lime, rising perpendicularly, and varying in height from two to twelve inches; appearing as though they had originally been formed by a gathering of lime and sand around sticks, which having decayed, had left the hollow tubes." A granite ridge, near this, creeps up in a series of fungus-like rocks; but no other granite is found along the coast. In another place were found some limestone hills perforated by the burrows of the Wombats.
CHAPTER III. VOLCANOES.
If burning mountains were not so common, they would be considered almost as miracles; but, like everything else, being frequently met with, they are comparatively little regarded. Various theories have been started to account for these phenomena, which seem to spring from some internal fire in the bowels of the earth, which occasionally breaks forth and discharges fire and smoke, together with a stream of melted stone and ashes, over the surrounding country. There are numerous volcanoes in various parts of the world, but as those of Europe are best known, a short account of them will be first given.
MOUNT ÆTNA.
This mountain stands on the eastern part of the island of Sicily. It is upwards of 10,000 feet high, and its summit is covered with snow, in the centre of which rises a little mountain about a quarter of a mile perpendicular, the sides of which are very steep. The plain or table-land from which this mountain rises, is about nine miles in circumference; and the little mountain is, in fact, the crater or mouth from which the flames proceed. It is formed entirely of stones and ashes, and in the middle there is a hollow about two or three miles in circumference, the inside of which is covered over with salts and sulphur of different colours. It goes shelving down like an inverted cone, the depth of which nearly corresponds to the height of the smaller mountain. From many parts of this crater issue volumes of sulphureous smoke, which, being much heavier than the superincumbent atmosphere, instead of ascending, rolls down the side of the mountain, till, coming to a more dense atmosphere, it shoots off horizontally, leaving a conspicuous track behind it. Loud noises are frequently heard from the crater, and before an eruption they increase to such a degree, as to be heard at a very considerable distance. The form of the mountain is a cone, very broad at the base, which is more than forty miles in circumference. The whole of the mountain is covered with volcanic substances, and near the base, these are mingled with so many marine bodies, that the mountain appears at some not very distant period to have been washed by the sea. The mountain is divided into three distinct zones, which are called the cultivated region, the woody region, and the desert region. The trees in the woody region are remarkably fine, and the cultivated ground is very fertile.
MOUNT VESUVIUS.
Mount Vesuvius is situated on the shore of the Bay of Naples. It is little more than four miles from the city of Naples; its base occupies an irregular space of about twelve miles in circumference; it rises conically to the height of about 3000 feet, and terminates in two peaks, one of which contains the crater. It is one of the extraordinary circumstances relating to this mountain, that though it has frequently overwhelmed the towns and villages at its base, the inhabitants have persisted in building fresh towns in exactly the same position as those that have been destroyed. The first fearful eruption of which we have any account was in 79, nearly two thousand years ago, by which, in the month of August in that year, the cities of Herculaneum and Pompeii were destroyed; not, as is sometimes supposed, by a stream of burning lava, but by showers of ashes, as is proved by the excavations which have been made. It was at this eruption that Pliny, the naturalist, venturing too near the mountain, lost his life. Several other eruptions followed, till in the year 1588, a new mountain suddenly appeared beside the old one. In 1779 a violent eruption took place, which was witnessed by Sir William Hamilton, who has left a detailed account of it. In 1822 was another considerable eruption, which continued more than twenty days. During this eruption a new crater was formed, from which since that time fire has continued to issue in the same way as from the old one. In every case when an eruption has taken place, it has been preceded by a fearful bellowing noise, which is generally heard for several days. When the eruption begins, the mountain throws up immense columns of fire, shrouded in the blackest smoke, and mixed with sand so fine, as to fill the eyes and ears with an almost impalpable powder. The fearful bellowing is repeated before each fresh explosion; and the flames when they burst forth, rush upwards with such force, as to carry with them not only large stones, but pieces of rock. The smallest stones appeared of the size of cannon balls; the greater number were like bomb-shells, but others were pieces of rock, five or six cubic feet in size, and some of most enormous dimensions; the latter generally fell on the ridge of the crater, and rolled down its sides, splitting into fragments as they struck against the hard and cutting masses of cold lava. Some of these stones, even when on fire, are extremely hard, but the larger ones are a complete paste of fire, and whilst at a red heat are easily divided. The stones are not always thrown up perpendicularly in the shape of a pillar of fire, but sometimes like a widely spreading sheaf, producing the most brilliant effect imaginable. The lava of Mount Vesuvius rarely extends above seven miles from the crater, while that of Mount Ætna flows to a distance of sometimes twenty and even thirty miles.
MOUNT HECLA.
This volcano, which has three summits, and is about 5000 feet above the level of the sea, lies about four miles from the southern coast of the island of Iceland, in full view of the ships sailing to Greenland and North America. "The surrounding territory has been so devastated by its eruptions, as to be entirely deserted; and the natives assert that it is impossible to ascend the mountain, on account of the number of dangerous bogs which are constantly emitting sulphureous flames and smoke." The more elevated and central summit is covered over with boiling springs and large craters, from which smoke is constantly issuing, and occasionally fire. When Sir Joseph Banks and his companions visited this mountain, they had to pass over a tract of land, seventy miles in extent, which was entirely covered with lava, and they found in one place a small lake, bounded by a perpendicular face of rock, covered with hardened lava, which resembled glass.
THE ORÆFA MOUNTAIN IN ICELAND.
This mountain, which is the loftiest in Iceland, has been rendered celebrated by an eruption which took place about a century ago. Nothing can be more striking than the account given of this calamity by the aged minister of the parish. He was in the midst of his service on the Sabbath, when the agitation of the earth gave warning that some alarming event was to follow. Rushing from the church, he saw a peak of the neighbouring mountain alternately heaved up and sinking; till at last the stone of which this portion of the mountain was composed ran down in a melted state into the plain, like melted metal from a crucible, filling it to such a height that no more of the mountain, which formerly towered to such a height, remains than about the size of a bird; volumes of water being in the meantime thrown forth in a deluge from the crater, and sweeping away whatever they encountered in their course. "The Oræfa then broke forth, hurling large masses of ice to a great distance; fire burst out in every direction from its side; the sky was darkened by the smoke and ashes, so that the day could hardly be distinguished from the night. This scene of horror continued for more than three days, during which the whole region was converted into utter desolation."