heart of Europe, which is analogous to the selvas of the Amazon. Compared with the north of Germany, the spring here begins late, and is short; the summer is foggy and stormy; and the mean temperature lower than that of more northerly districts.

Proceeding in a westerly direction, the flat land traverses the north of Germany, and here forms a series of ascents and descents from the shores of the Baltic to the foot of the Alps, in which however the ascent becomes more marked as the south is approached. A line drawn from the island of Usedom at the mouth of the Oder, through New Strelitz, Berlin, Leipsic, Greitz, Baireuth, Ratisbon, and Munich, to the Tegern Lake, divides Germany into two parts, the east and west; and along its whole extent, there is only a single mountainous tract to pass over, which commences at Greitz about the middle distance. Following this line from the north, the traveller gradually rises by a series of terraces, the loftiest of which, at whose southern margin the Alps with their high masses plunge into the depths beneath, stands about 1400 feet above the spot where he commenced his journey. The physiogonomy of the country through which he passes is of the most varied kind. At its northern extremity are the gently undulating hills of Usedom, with their beautiful and verdant forests, affording in open spots, on the one hand, a view of that billowy sea which only terminates with the sky, and on the other the tranquil waters of the mouth of the Oder are seen, with the coast of Pomerania, enlivened by numerous sails which the active commerce of Stettin sends into distant lands beyond the ocean, into other hemispheres and other climates. The coast of Pomerania is to a considerable extent an open cornfield, without a tree or bush, a fruitful solitude, wearisome from its sameness. Beyond, at the horizon, a sharp line arrests the eye, the heights of Mecklenburg, a district where the scene alters, and the abodes of a rich population appear, enclosed in fruitful gardens, around the capital of the beautiful country of New Strelitz. Farther towards the south the soil changes; sand becomes the prevailing element, and woods of the gloomy pine and common fir intermingle with the meagre sand-fields on which man can only obtain a scanty subsistence from the earth. This is the prevailing character of the country through the Mark of Brandenburg, the whole of which is covered with erratic blocks, many of enormous size, which some great inundation has apparently borne hither from their native Scandinavian bed. Reaching the Elbe, a new soil commences on its southern bank; luxuriant corn-fields appear, which only become more productive, till the fruitful fields of Leipsic open before us. The great plain we have been following from the Baltic, ends at Greitz, on the White Elster; and, at the south bank of the river, the traveller ascends the first terrace of the plateau of Southern Germany. It is not, however, a ridge which he attains, but a plain, reaching to Gera, where he beholds before him plains again and again, which rise like terraces one above the other. Farther on, he wanders through narrow valleys overshadowed by the powerful stems of the red and white fir, leading to the foot of the mountain chain which abuts against the ramparts of Bohemia. The valley plain of the Maine is now entered, presenting variegated meadows, rich corn fields, the red roofs of innumerable villages; and afterwards we proceed to the plateau of the Upper Palatinate, which, by its barrenness, strikingly contrasts with the region we have just left. The northern fir, here and there mixed with the pine, becomes again the prevailing tree; and the country has all the aspect of the plains of Brandenburg, till we arrive, by a wood of pines passing over a mountain ridge, within sight of the venerable Ratisbon. Wild and deep rushes the Danube past its walls, not so much splashing as foaming against the pillars of the lofty bridge which conducts us across a fertile plain, with wavy elevations, to the valley of the Isar, which forms only a moderate depression in it. Here, standing on some heights near the small town of Freising, the traveller sees on the southern horizon what he thinks at first a mere vapour in the aira heap of clouds, the edges of which appear serrated. It is the Alps! Over a plain more

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smooth and level than any which are observed in the north of Germany, we travel to the capital Munich, which, with all its palaces and monuments, stands in the midst of a large unattractive level, extending with few interruptions to the Tegern lake, one of the entrance gates of the Alps.

The level land of the north of Germany extends westward through Holland, Belgium, and France; and in the latter country it surrounds in a great arc, with but few interruptions, that system of mountains, which, rising in Cevennes, extends to the Lower Rhine. Great diversity in the form and soil of the surface, and the nature of its cultivation, is the character of this part of the neighbouring kingdom, which, with fertile and most fruitful districts, exhibits true steppes and actual deserts. The following sketch of a portion of this flat land-that on the western coast-is indebted for several of its features to the lively pictures of modern travellers. Setting out from the Pyrenees, and proceeding to Bourdeaux, we pass over the department of the Landes, the direct track lying through a wild sandy desert, in many parts too unproductive even for sheep walks, in others presenting forests of pine of vast extent. The peasantry live in solitary cabins ; employed in cultivating the soil where it is not absolutely sterile; tending hardy sheep, or making charcoal in the woods; traversing the deserts on stilts in order to pass the intervening morasses dry-shod. Reaching the wide and bay-formed mouth of the Gironde, in which its waters lose the wild tempestuousness which marks their early career in the Pyrenees, we meet with a country on the right bank, which in appearance is tolerably

rich, covered with plantations of vines, and sinking softly in innumerable hills down to the sea. The chain of sand on the sea-coast is bordered by a beautiful alternation of fields, woods, and meadows, with villages bearing the aspect of cleanliness and comfort, their white houses and green window-shutters contributing to the agreeable effect of the landscape. Here is the district of Saintonge, which, with its waving valleys and classic reputation, acquired in poetry the name of the Flower of France. Along the whole coast, lighthouses have been erected, that of the tower of Cordouan, built by order of Henry IV., being the most ancient and admired, and the most celebrated in France. It stands on a rock two miles out amid the waves, announcing the vicinity of a dangerous coast; and

the fancy readily turns to it as a memorial of sorrow, on the grave of a city engulfed by the encroaching waters-the Novioregum of antiquity.

A melancholy spectacle is presented farther north, towards Rochefort, that of flat barren wastes, and salt marshes, with here and there a spot planted with trees, and occasionally there is a village deserted and in ruins, high grass, and elder bushes mingling with its remains. It is hence with pleasure that the traveller descries the dome of the hospital and the walls of Rochefort; but, notwithstanding its fresh and smiling aspect, and the pleasant murmuring of its large elms, the town has been literally snatched, at an immense cost, from the morass, and no sooner is it passed than the dismal swamp again appears. The whole road to La Rochelle is of a melancholy character, and especially so if traversed under a cloudy sky. It crosses a dreary steppe, of which the sea is the limit on one hand, and which is apparently boundless on the other. At distant intervals are a few tamarind trees; or a lonely farm-house sends out its gloomy smoke; or some conical hay ricks are passed, standing round a neglected barn; or a meagre horse, with scanty mane, stands beside the road, and neighs at the approaching storm. The sea beats against the foundations of the road, and the sea-mews cross it, driven by the wind, their white wings contrasting strongly with the dark and louring clouds. Thus, at both extremities of the flat land of Europe, the western, where it reaches the Atlantic, and the eastern, where it ends with the Caspian, we find the same superficial aspect -a monotonous, desolate, and treeless waste.

CHAPTER IV.

CAVERNS AND SUBTERRANEAN PASSAGES.

HEN we reflect upon the manner in which the solid crust of the earth appears to have been formed, upon the powerful upheaving force by which its elevated sites have been raised, and the posterior agency of subterranean gases, volcanoes, and earthquakes, it is natural to expect chasms in the surface of tremendous depth, spaces also in the interior which have not been filled up with masses of stone similar to the materials of the earth itself, but by water, air, or vapour, with those cavities of grotesque and romantic appearance that are found in mountainous regions. There are few natural objects which have more awakened curiosity, or more strongly affected the imagination, than the hollow places, of various form and size, common in districts which have been subject to great physical disturbance. Their seclusion and gloom-their fantastic architecture-the effect of torch-light upon their numerous crystallisations-the augmentation of sound and its reverberation - together with their unknown extent in many cases-all these causes

contribute to invest the cavities of the earth with exciting interest; nor is it strange to find them interwoven with the traditions and mythologies of unenlightened nations. On account of their sombre interior and strange outline being adapted to impose upon an ignorant populace, and give effect to religious observances, the priesthoods of antiquity localised in caverns their false divinities, and celebrated sanguinary rites upon the natural altars found in their recesses. A cave, with a priestess seated upon a tripod at its mouth, pretending to inhale a vapour from the interior which inspired a knowledge of future events, the gift of Apollo; was the original Delphian oracle, reverenced by the mind of Greece, and resorted to by the proudest monarchs of the ancient world. The cavern, along with the deep forest, commended itself to the primitive inhabitants of northern Europe by its mystery and gloom as an appropriate spot for the performance of a barbarous worship, and many local titles of such sites preserve the memory of their former uses. An instance of this we have in Thor's cave, or, as Darwin calls it,

"The blood-smear'd mansion of gigantic Thor,"

a broad excavation on the face of a huge rock in the limestone district of Derbyshire, divided into two chambers, one beyond the other, with a detached stone at the further extremity, where the light of day is very much subdued. But in India the largest use has been made of caverns for religious purposes, and immense pains have been taken with their adornment, extension, and architecture, at Elephanta, Salsette, and Ellora, where there are elaborately wrought temples constructed, probably out of small natural crevices in the rock. We shall now refer to a few of those cavities which are entirely the workmanship of nature, with whose form man has not intermeddled, and notice the principal phenomena which they exhibit.

That extensive cavities exist in the interior of the crust of the globe is evident from the phenomena of volcanoes and earthquakes. They are not accessible to observation, but the repeated tremblings of the soil in various places, and experiments made of oscillations of the pendulum, point to the conclusion, that there are large underlying hollows, at no great distance from the surface, of which the superficial land forms the

Jorullo, Mexico.

roof. The table-land of Quito, and the burning mountain of Jorullo, each surrounded by the most powerful volcanoes upon the earth, are supposed to be examples of this. Condamine believed that a considerable portion of the former mountain was to be regarded as the dome of an enormous vault; and Parrot has shown it to be highly probable, by a careful calculation, that a cavity of at least a cubic mile and a half exists beneath its surface. The rumbling noise, like that of distant thunder, which on the testimony of Humboldt usually precedes and accompanies the eruption of its volcanoes, affords evidence in favour of this sup

position, and as an increase of the subterranean vacuity must be the necessary consequence of every outbreak, it is not at all an improbable event, that the blooming landscape will ultimately fall in, and this piece of table-land become an immense depression. The quantity of material scooped out of the interior of the earth by volcanic action is

immense, and calculated to produce vacuities in which the largest mountains would have ample space. It has been estimated that Etna in one of its last most important eruptions, that of the year 1769, threw out a mass of lava equal in volume to a cone 5820 feet in height, and 11,640 feet in breadth, or nearly four times larger than Vesuvius. Fourteen such eruptions would produce a mass equal to Mont Blanc, reckoning from the level of the sea, and twenty-six such large eruptions have occurred since the twelfth century. In the year 1783, when the earthquake of Calabria occurred, the Skaptar volcano in Iceland poured forth a stream of lava fifty miles long, between twelve and fifteen broad, and from one to six hundred feet in thickness, which must have been equal to six times the mass of Mont Blanc, and two and a half times that of Chimboraço. Hence, it is a common event, in countries subject to great volcanic activity, for portions of the surface to fall in, the subsidence frequently becoming the bed of a lake. A part of the forest of Aripas in the Caraccas thus subsided in the year 1790; a lake was formed nearly half a mile in diameter, and from eighty to a hundred yards in depth, and for several months after the trees of the forest remained green under the water. the same year, in Sicily, at Santa Maria de Nisremi, a portion of the country three Italian miles in circumference sank thirty feet deep. Occurrences of the same kind appear to take place in the depth of the sea, the falling in of its bed being indicated on the surface of the waters by their sudden retreat and violent agitation on their return. A remarkable example of this phenomenon took place at Marseilles, on June 28, 1812, when the water in the harbour suddenly sank, then rushed out with great rapidity, and returned with equal violence; a movement which was repeated several times, till the equilibrium was restored, occasioning considerable damage to the shipping. Instances of similar events are innumerable, which serve to prove the existence of cavities, both in the interior of the exposed crust of the earth, and these parts of it over which the ocean rolls.

In

To Humboldt we are indebted for a large amount of information respecting the cavities which appear upon the surface, the chief differences of their form, the beds in which they are found, and the causes which may have originated them. In the primary rocks, caverns are relatively fewer than in the later deposits, while the oldest masses of the granite and gneiss formations are particularly destitute of them. The principal are wide fissures, sometimes of unknown depth, and those hollow passages which occur in Switzerland and Dauphiné, called crystal caves, owing to their walls being richly furnished with pillars of rock crystal. Similar vacuities occur in the gneiss of the Pine mountain in the neighbourhood of Wiesenthal, but they are not important. In Sweden and Norway, the granite presents fissures and caves of extraordinary extent, and perfectly unexplored, hitherto; such as the cave of Marienstadt, the end of which is not known, and the enormous deep hole at Frederick stall, where a stone thrown in only gives the echo of its fall in a minute and a half or two minutes; an observation which, if well founded, would give, on the calculation of Perrit, a precipitous depth of 59,049 feet, the highest estimate, or 39866 feet, the least; that is, from twice to three times the height of Chimboraço. It is the primitive limestone that supplies the most numerous examples of caves and grottos in the primary rocks; and if these yield in point of size to the later limestone formations, this arises from the inferior extent of the primitive limestone, rather than from its incapacity to form caves. In the transition mountains, and those of stratified structure, it is still the limestone in which the more extensive caves are found, of which those of the Hartz, the splendid caverns of Derbyshire, and those of the Carpathians, are well known. Caverns most frequently occur in the mountains of stratified limestone; and among these, one of the most modern formations, the Jura limestone is particularly distinguished, and was therefore termed