In the Deccan, half-way between Bombay and Nagpur, there is a very remarkable salt lake. It is a circular hollow, about one mile across, and from 300 to 400 feet deep, having at the bottom a shallow lake of salt water without any outlet. This hollow, I must tell my reader, is ascribed by scientific men to a volcanic explosion.

There are so many lakes of salt, which are completely isolated and so many miles from the sea, that it is next to impossible to account for their existence if we do not ascribe them to volcanic action. If they are situated in low-lying districts, we may justly presume that at one time the sea must have been present, or that the deposition must have resulted from occasional, or tidal, overflow of salt water; but when they are many miles from the coast, and many feet above or below the sea-level, then they may be due to volcanic agency; and we shall find further on several other salt lakes of variable depths or altitudes which would seem to corroborate this hypothesis. The sea is undoubtedly a most formidable agent in the disintegration of land, and often destroys whole tracts, forcing its resistless waves into the interior of continents, and then, owing to some unexplained cause, retiring to its original boundary. This may take centuries to complete, for revolutions effected by nature are not accomplished speedily, unless there is some sudden spasmodic upheaving, arising from earthquakes or storms. In 1282, the isthmus uniting Friesland with the north of Holland was totally destroyed by violent storms. In our own country a similar phenomenon occurred in the year 1475, when a large tongue of land at the mouth of the Humber was entirely broken up and carried away by the sea. In 1510 an irruption of the Baltic formed the Frische-Haff, an opening 6000 feet broad, and from twelve to fifteen fathoms in depth. The eastern coast of England is continually receding, owing to the encroachment of the sea. The rate of encroachment of the sea at Owthorne, in Yorkshire, is reckoned at four yards in every year, and several villages have been swallowed up by the ocean; and in like manner the cliffs of Norfolk and Suffolk are suffering a continual decay.

Though the sea is so destructive an element, it is also an agent in the reproduction of land. The rocks and sand washed away from one place are conveyed by tides and currents far into the sea, and are deposited in strata, and then, in course of time, form shoals and banks, which subsequently become promontories and islands. Alluvial land has thus been formed, and in a similar way have many of the stratified rocks been deposited; and as animals and plants have been carried away and imbedded in the deposits of rivers, or floods, so at some future period, though countless ages may elapse during the process, will such animals and plants be discovered deposited in these newer strata, just as we find organic remains in the older rocks. The gradual deposition of strata has been the work of an incalculable period of time, but the process may be traced every day in the sections of marine estuaries and lakes. Owing to this continual receding of the land in one part, and elevation of land in another, there is an incessant change, from which, though occupying many ages, and proceeding so slowly that it would be unobservable were it not for accurate investigation, we may easily conjecture that what is now land may at one time have been the bed of the ocean, and where the sea now sweeps with overpowering fury, there may once have been meadows and forests. The salt lakes, if not originating from volcanic force, no doubt are the remains of the great ocean, which, when it receded, left here and there, in what once were luxuriant valleys, large reservoirs, indicating that in bygone ages it had covered the land.

In Germany, Spain, Italy, Hungary, and Poland, there are extensive mines of rock-salt, and also in various other parts of Europe.[36] There are also large mountains wholly composed of this fossil salt, two of which are in those provinces of Russia known as Astrakhan and Orenburg; and in the Crimea salt is said to be daily accumulating in the inland lakes. In Asiatic Russia there are extensive beds of salt, near Lake Indur, in lat. 48° 30´, long. 69°. The Caspian Sea, called by the Turks “Cozgoun Denghizi,” “the sea of crows and cormorants,” is “a great salt-water lake,” according to Dr. William Smith, though Dr. Lemprière says that “its waters are sweet.”

The most interesting salt-mine is that of Wieliczka, near Cracow, in Galicia; it has been celebrated for centuries, and has been worked for the last six hundred years. This wonderful mine is excavated in a ridge of hills at the northern extremity of the chain which joins the Carpathian mountains. When the stranger reaches the mine there bursts upon his view a little world, the beauty of which is scarcely to be imagined. He beholds a spacious plain containing a kind of subterranean city, with houses, carriages, and roads, all scooped out of one vast rock of salt, as bright and glittering as crystal, while the blaze of the lights continually burning for the general use is reflected from the dazzling columns which support the lofty arched vaults of the mine, which are beautifully tinged with all the colours of the rainbow, and sparkle with the lustre of precious stones, affording a more splendid and fairy-like aspect than anything above ground can possibly exhibit. In various parts of this spacious plain stand the huts of the miners and their families, some single, and others in clusters, like villages. They have very little communication with the world above them, and many hundreds of persons are born and pass the whole of their lives here.

Through the midst of this plain lies a road which is always filled with carriages laden with masses of salt from the furthest part of the mine. The drivers are generally singing, and the salt looks like a load of gems. A great number of horses are kept in the mine, and, when once let down, never see daylight again.

Such is the marvellous salt-mine of Wieliczka, which is more renowned on account of its magnitude, its age, and the weird and almost supernatural aspect it presents to the visitor, than any other. Those subterranean palaces, with their magnificent appurtenances, their fantastic occupants, and other dreams of the imaginative, are not more strange or astonishing to the fascinated reader of romance than this extraordinary, glistening, cavernous, mineral city, with its numerous lamps, its crystallised walls, its roads, and the plaintive songs of the drivers as they drive their horses through its sunless thoroughfares, presents to the eyes of the surprised traveller.

There are valuable mines of salt in France, and in Greece, near Missolonghi, but these have no special points of interest connected with them.

In Abyssinia there are extensive and inexhaustible beds of salt, which is used in quite a different way from what it is in other countries, for little bars of it are circulated in place of small coin; but it is only when it reaches the Amhara and Galla districts that it becomes valuable.[37]

In other parts of the African continent there are large mountains of rock-salt, and those of Tunis and Algiers are especially notable.