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islands rising out of their bosom, which add greatly to the effect of their appearance. They are often small, generally transparent, placid, and solitary; and, being altogether without artificial embellishment, the naked grandeur of the engirdling cliffs renders them far more impressive than those which are enriched with towns, and ornamented with villas, like the lakes of Northern Italy. In Scotland, the Scandinavian peninsula, the Alps, and Andes, many sheets of water are found set like gems among the mountains, seldom visited except by the flocks of wild-fowl which float undisturbed upon their breast, where the silence is rarely broken but by their cry, and the splash of the rills descending into their basin. At the head of the river Kandal, in the Swiss canton of Berne, there is a lake of this kind, formed by the aggregated waters of numerous springs, which pour their torrents from the neighbouring mountains. The lakes of secondary regions are characterised by the softer beauties of the landscape, though not without bold and striking features. The banks are gently undulating, and usually adorned by cultivation. Such is the general aspect of the Italian, English, and Irish lakes; those of Killarney, amid the mountains of Kerry, in the sister island, being remarkable for their picturesqueness. They are three in number, mutually connected, but varying to some extent in their scenery. The upper lake lies in a hollow formed by some of the loftiest of the Irish mountains, so that its character is in the highest degree magnificent and sublime; but softness and beauty are the prevailing attributes of the two others. Their banks exhibit gentle swells covered with the freshest verdure, with lovely islands in their waters, upon which are trees worthy of a primeval forest; and it is in this contrast of the mild and graceful with the wild and rugged, that the chief charm of the Killarney lakes consists. Those of alluvial districts have few external recommendations. Their shores are usually low and level, and their waters are often stagnant, in many cases yielding unhealthy exhalations from the marshes which form their borders. The South Baltic coast, that about the mouths of the Nile and Mississippi, and the plains around the Caspian, abound with these lakes, which commonly partake of the saltness of the contiguous seas.

England presents few examples of lakes, and none of any considerable size, though Winandermere, the largest, exhibits, along with Ulswater, Derwent, and Conistonwater, many natural beauties. They have indeed been preferred by some of our countrymen to the Swiss lakes, on account of being ornamented with woody islands, in

which those of Savoy and Switzerland are deficient; and perhaps, apart from this, a physical cause may be found for the preference, in the case of passing visitors, independent of all national partiality. Owing to the greater transparency of the atmosphere in Switzerland, the giant mountains east of the Lake of Geneva do not appear at first more elevated than the comparative dwarfs at the head of Ulswater, to an eye unaccustomed to so clear a medium. Hence, the first impressions of the Alps are commonly the feeblest, a due appreciation of their magnitude being the fruit of acquaintance; whereas, a denser atmosphere gives to our scenery fictitious features, which acquaintanceship corrects. In Scotland the lakes are more numerous and important, the superficial dimensions of each of the following twenty-four exceeding the area of Winandermere.

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In Ireland they are still more considerable, Lough Neagh, in the centre of Ulster, being the largest lake in the United Kingdom, more than three times the size of Loch Lomond, having a superficial extent of nearly 100,000 acres. The total superficial area of the Irish Lakes is supposed to amount to 455,399 imperial acres. The annexed table gives the extent of the principal European lakes.

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The largest lake in the world, the Caspian, is geographically situated both in Europe and Asia, but is commonly classed with the physical features of the latter country, and styled a sea from its size and saltness. Measured according to its curvilinear shape, in the middle of its breadth, it exceeds 900 miles in length, with an average width of 200, and has an area of nearly 160,000 square miles. The next in extent, that of Aral, has, with the Caspian, received the denomination of an inland sea, and is nearly a fourth part of its size. The Lake Baikal, in Siberia, has a computed area of 20,000 square miles, and, both in central and western Asia, there are large expanses of nearly equal extent. In Africa, lagoons occur along the coasts; small briny pools, also, are common in the deserts; but the interior is a great mass of solid land, seldom broken by either rivers or lakes. The chief of the latter, and the best known, is that of Dembia, nearly centrical in Abyssinia, measuring, in Bruce's map, 65 miles in its greatest length. The Tchad is larger still, but we are only very imperfectly acquainted with it. It lies in the Negro

land of the Arabs, in 15° E. long., and 13° 30′ N. lat., and is supposed to be about 200 miles long, and 150 broad. The northern part of the western world is pre-eminently the country of lakes, presenting the largest masses of fresh water to be found upon the surface of the globe. The following statement shows the area of the principal:

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In South America, the Lake of Titicaca, in Upper Peru, covers a surface of about 4000 square miles; and immense swampy plains and lagoons are common along the course of the rivers.

Lakes are sometimes considered under the two divisions of fresh and salt water, but there are many occupying intermediate stations with reference to these extremes. We shall follow another arrangement of them, into four classes, which will more fully embrace their physical conditions, and then notice some remarkable phenomena, by which several are distinguished.

1. There is a class which have no apparent affluents or outlets. They are fed chiefly by subaqueous springs, and occur frequently in hollows, which have the appearance of extinct volcanic craters. They are generally small, but of more stable character than the larger sheets of water formed by rivers. Not receiving any great superficial current, they are not subject to those changes of their depth and outline, which take place in the lakes with affluents, through deposition of the mud and sand brought into them by turbid torrents. Collections of water of a similar kind abound in the great steppes of northern and western Asia. They are called lakes, but are perhaps more properly pools, being formed of accumulated rains and melted snow, which are largely, and in some cases entirely, evaporated by the summer heat, though several have a circumference of from ten to twelve miles, and a depth of six or seven feet. Their waters are commonly saline, and what is most remarkable, and hitherto unexplained, sheets of fresh water are found in their immediate vicinity. The most considerable example of this class is the Lake of Tuzla, which lies northward of the great range of Taurus, on the high central plateau of the Lesser Asia. Though narrow, it extends fifty miles in length, and is so extremely salt, that no fish or aquatic animal can live in it. Even the wild fowls are afraid to venture upon its waters, for by so doing their wings become stiff with a thick coating of salt, and any substance thrown into them speedily receives a saline incrustation. Strabo, the geographer of antiquity, a native of the peninsula, was personally acquainted with this lake, and mentions these circumstances, the accuracy of which, modern travel has confirmed. The Sultan Murad IV. made a causeway across it, upon the occasion of marching his army to the attack of Bagdad, for, owing to excessive evaporation during the summer and autumn heats, the lake is extremely shallow. The remains of this causeway are now almost concealed by a saline encasement, and a thick crust of solid salt covers the bed of the lake.

2. Another class have outlets, but no apparent affluents. These lakes usually occupy a high elevation above the level of the sea, and derive their supplies from subterranean springs. One on Monte Rotondo, in the island of Corsica, is at the height of 9000 feet. They are not inconsiderable in number, and are frequently the sources of important rivers. The course of the great Volga may be traced up to a lake of this kind, but which is only slightly elevated above the sea-level.

3. A third class receive affluents, but have no outlets. exceedingly rare, but they are the most peculiar of all.

Lakes of this description are
That of Celano in Italy, the

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ancient Fucinus, exhibits a superficial extent of 100 square miles, and has no natural outlet for its waters through the hills by which it is surrounded. Owing to its rise in former times, an immense tract of excellent land was lost, and the Roman senate was petitioned to drain it, a scheme which Julius Cæsar is said to have contemplated. For effecting this purpose a tunnel three miles long, through one of its mountain boundaries, was formed by the Emperor Claudius; and the younger Pliny relates the barbarous ceremony of its opening. During the space of eleven years, thirty thousand men were employed in digging the passage, and when everything was ready for letting off the water, a naval spectacle was exhibited upon it. A great number of condemned criminals were ranged in separate fleets, obliged to engage in earnest, and to destroy one another for the entertainment of the court, and the multitude of spectators who covered the hills. A line of wellarmed vessels and rafts, loaded with soldiers, surrounded the scene of action, in order to prevent any of the victims from escaping. Pliny states, however, that when this savage diversion was ended, and the operations for opening the tunnel commenced, the emperor was very near being swept away and drowned, by the sudden rush of the waters towards the vent. The tunnel was speedily choked up, and the Celano lake rose so much as to cover ten thousand acres of fertile soil, when it was again re-opened, and other hydraulic means adopted to keep the waters to a low level. Lakes of this description, without any outward current, though continually receiving large streams, are principally found in Asia, and are for the most part salt. Such is the great Lake of Urameah on the Persian frontier, which, according to Colonel Kinneir, is three

hundred miles in circumference, and is land-locked amid the picturesque mountains and valleys of Azerbijan. Though constantly fed by numerous currents, it has no outlet; yet there is no increase of its waters, but a gradual diminution, the waste through evaporation being greater than the supply. The lake is intensely salt, as appears from the depositions left upon the beach. For some distance from the brink, a perfect pavement of the solid mineral may be seen under the shallows. A village is pointed out as having once overhung its waters, which is now separated from them by a strand covered with salt, a quarter of a mile broad. Beyond a chain of hills to the north-west lies another example, the Lake Van of Armenia, so celebrated for its beauty by the eastern writers, both in prose and verse. It occupies the bottom of a volcanic amphitheatre, is upwards of 240 miles in circumference, and receives the waters of eight rivers without sending off any

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By far the most remarkable instances of this class of lakes are the Caspian, the Sea of Aral, and the Dead Sea. The majestic volume of the Volga pours into the former, with the Ural, the Kur, and the Aras; yet, notwithstanding these great constant accessions, the Caspian dispenses no surplus waters through any outlet

into the adjacent districts. It was once deemed a perplexing problem, how the contributions of its rivers were

disposed of; but the evaporation from so vast an expanse during the heat of summer must be enormous, fully adequate not only to prevent any permanent rise of its level, but gradually to diminish it. The sea of Aral likewise, to the eastward, exhibits the same peculiarity. It received the Jaxartes and Oxus of the ancient geographers, now the Sihoun and Amou, but no stream issues from its banks. Both these bodies of water are salt, and abound with marine productions. All the varieties of sea animals are common to them that are found in the Black Sea, except those transient visitors which arrive in the latter for the purpose of spawning; and hence it has been conceived probable that both were once connected, forming a branch of the main ocean-an extension of the Euxine. The separation of the three, if ever they were united, may have arisen from the deposition of the alluvial conveyed in the course of ages by the Volga and the Don, together with the subterranean action of elastic fluids which belong to this volcanic territory. The Dead Sea, in the south of Palestine, called also by the Latin geographers Lacus Asphaltites, and by the Arabs Bahr Lout, or Lot's Sea, though very insignificant in size,

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