Essay on the Theory of the Earth
Part 32
In 1799, a cave, remarkable for its situation, was discovered, which connects in some measure those of the _Hartz_ with those of _Franconia_. It is the Cave of _Glücksbrun_, in the bailiwick of _Altenstein_, in the territory of _Meinungen_, on the south-western declivity of the chain of the _Thuringerwald_ (Blumenb. _Archæol. Telluris_, p. 15. _Zach. Monate. Corresp. 1800, January_, p. 30.) It is the same which M. Rosenmüller names _Libenstein_, on account of its being on the road from _Altenstein_ to this latter, which is a bathing place. There is a description of it by M. Kocher, in the _Magazin für Mineralogie_, by M. C. E. A. De Hof, 1st band. heft. iv. p. 427. The limestone in which it is situate rests upon bituminous schist, and, rising much upwards, comes to rest upon primitive rocks. The limestone varies in hardness and in the nature of its fracture, and contains marine petrifactions, such as pectinites, echinites, &c.
In making a road, there was discovered an opening, from which a very cold air issued, which determined the Duke of Saxe-Meinungen to have it farther examined. A narrow passage, of twenty feet in length, was found, which led to a cave of thirty-five feet, having a breadth of from three to twelve, and a height of from six to twelve, according to the places, and terminated by a large piece of rock, which was removed. The labour of two years discovered and cleared a series of caves connected together, and of which the bottom rose and fell alternately. They terminate in a place where water flows; but various lateral fissures make it probable that there are still several caves which have not been opened, and that they perhaps form a sort of labyrinth.
The bottom and walls of this cave are furnished with the same mud as the others, but blacker. The bones were pretty numerous, and tinged with the same colour, but only two tolerably entire skulls were obtained. That of which M. Kocher gives a figure, is the species of bear named _Ursus spelæus_. There are also caves of this kind in Westphalia. J. Es Silberschlag, in the _Mem. des Naturalistes_ of Berlin (_Schriften_, vol. vi. p. 132), describes the one called _Kluter-hœhle_, near the village of _Oldenforde_, in the county of _Mark_, on the edge of the _Milspe_ and _Ennepe_, two streams which fall into the Ruhr, and with it into the Rhine. Its entrance is about half-way up a hill called _Kluterberg_, is only three feet three inches high, and faces the south. The cave itself forms a true labyrinth in the interior of the mountain.
Not far from this, in the same county, at Sundwich, two leagues from _Iserlohn_, is another cave, which, for about twenty-five years back, has furnished a very large quantity of bones, part of which has been carried to Berlin, and the rest has remained in the country in the hands of various individuals[435].
If we cast a glance upon a general map, it is not difficult to perceive a certain continuity in the mountains in which these singular caves occur. The Carpathians join with the mountains of Moravia and those of Bohemia called _Bœhmerwald_, to separate the basin of the Danube, from those of the Vistula, Oder and Elbe. The Fichtelgebirge separates the basin of the Elbe from that of the Rhine. The Thuringerwald and the Hartz continue to limit the basin of the Elbe, by separating it from that of the Weser.
These different chains have but slight intervals between them. The caves of Westphalia alone are not connected in so evident a manner with the others.
Very lately, bones have been discovered in a cavern, which extends more towards the south, and is even situate on the other or Italian side of the Alps. It is that of _Adelsberg_ in _Carniola_, a place situate on the great road from _Laybach_ to _Trieste_, and about half way between these two cities. The whole of this country is full of caverns and grottoes, which have given rise to numerous sinkings of the surface, thus giving a very singular appearance to the country. Several of these caverns have long been celebrated among naturalists. That of _Adelsberg_ is generally visited by travellers, on account of its being near the highway, and because a river called the _Piuka_ or _Poike_ is lost there, forming a subterranean lake, and emerging again on the north side, under the name of _Unz_. A hole which the Chevalier de _Lowengreif_ discovered in 1816, in one of its walls, at the height of 14 fathoms, conducted him to a series of new caves of vast extent, and of incomparable beauty, from the lustre and variety of their stalactites.
A part of these caves was, however, known, and must be, or have been accessible, by some other place, for inscriptions were found in them with dates, from 1393 to 1676, together with human bones, and entire carcases, that had been buried there. A German pamphlet was published at Trieste, in which are described all the windings of these subterranean passages, their different halls, their domes, their columns, and all the other appearances produced by their stalactites. We shall not follow the author (M. de _Volpi_, Director of the School of Commerce and Navigation at Trieste) through this immense labyrinth. Let it suffice to say, that this zealous naturalist asserts his having proceeded more than three leagues, almost in a straight line, and that he was only stopped by a lake which rendered it impossible to go on. It was about two leagues from the entrance that he discovered bones of animals, of which he gives figures, and which he describes under the name of Palæotheria. He had the politeness to communicate to me, says Cuvier, his drawings the year before, but it appears my reply did not reach him, for he makes no mention of it in his book.
Be this as it may, his figures clearly shewed that the bones in question belonged to the great cave-bear. In fact, several of these bones having been presented to the Congress of Laybach, _Prince Metternich_, whose enlightened taste for the advancement of knowledge has already been of so much service, had the goodness to address them to Cuvier, who disposed them in the Royal Cabinet, where any one may satisfy himself as to their species.
There are, without doubt, caves in many other chains, and several are known in France. Caves occur in Suabia, but no bones have been found in them; and, in general, it appears, that, before the last discoveries, and especially that which has been made in Yorkshire, none were known but those of Germany and Hungary that were rich in bones of carnivora. In truth, the rock of _Fouvent_, and which contains in one of its cavities bones of hyenas, and at the same time those of elephants, rhinoceroses and horses, might be considered as belonging to this order of phenomena; but as it was not explored to any depth, it cannot be certain that it is so.
The case is different with the _Kirkdale_ Cavern. It having been visited immediately after its discovery by several well informed persons, and especially by Mr Buckland, every thing has been made known with respect to it. It is situated in the East Riding of the county of York, twenty-five miles NNE. of the city of _York_, and at about the same distance to the west from the sea and the town of Scarborough. The small river of _Hodgebeck_ is lost under ground in the neighbourhood, much in the same way as the _Piuka_, near _Adelsberg_. It is placed in one of the limestone hills which form the northern boundary of the vale of _Pickering_, the waters of which fall into the Derwent. Mr Buckland compares the stone to that of the last strata of the Alpine limestone, such as are seen near Aigle and Meillene.
It was in the course of the year 1821, that some labourers working at a quarry, discovered by chance the opening, which was closed by rubbish, covered over with earth and turf. It is about 100 feet above the neighbouring brook. It can be entered to the distance of 150 or 200 feet, but we can only walk erect in some places, on account of the stalactites. On its sides there are seen spines of sea-urchins and other marine remains, incrusted in the mass of the rock; but it is on the bottom, and there only, that there is found the stratum of mud, of about a foot thick, stuck full of bones, as at Gaylenreuth. This mud, and the bones which it contains, are, in various places, covered or penetrated with stalactite, especially near places where the rock has lateral fissures.
The discovery having acquired much celebrity, a great number of people procured bones from it, and placed them in various public depots. Specimens have been deposited in the York Institution, that of Whitby and Bristol, the British Museum, the Museum of Oxford and Cambridge, and by Mr Young of Whitby, in the College Museum of Edinburgh; but the finest collection of the bones of Kirkdale was presented to Cuvier, and by him deposited in the Royal Cabinet in Paris. The greatest number of these bones without comparison, belong to hyenas of the same species as those of the caverns of Germany; but there are also many of other large and small animals, which Mr Buckland supposes to form twenty-one species. From the pieces which I have under my eye, says Cuvier, there indisputably occur bones of the _elephant_, _hippopotamus_, _horse_, an _ox_ of the size of the common _deer_, _rabbits_, _field-rats_; also bones of some other carnivora, namely, of the _tiger_, _wolf_, _fox_, and _weasel_. All these bones and teeth are accumulated on the ground, broken and gnawed, and there are even seen marks of the teeth which have fractured them. There are even intermixed with them excrements which have been recognized as perfectly similar to those of the hyena[436].
The hills in which these caverns occur resemble each other in their composition: they are all of limestone, and all produce abundance of stalactites. These stalactites line the walls, narrow the passages, and assume a thousand various forms. The bones are nearly in the same state in all these caverns: detached, scattered, partly broken, but never rolled, and consequently not brought from a distance by water; a little lighter and less solid than recent bones, but still in their true animal nature, very little decomposed, containing much gelatine, and not at all petrified. A hardened, but still easily frangible or pulverisable earth, also containing animal parts, and sometimes blackish, forms their natural envelope. It is often impregnated and covered with a crust of stalactite. A covering of the same nature invests the bones in various places, penetrates their natural cavities, and sometimes attaches them to the walls of the cavern. This stalactite is often coloured reddish by the animal earth which is mixed with it. At other times its surface is stained black; but it is easy to see that these appearances are caused by modern occurrences, and have no immediate connection with the cause which brought the bones into these cavities. We even daily see the stalactite increasing and enveloping here and there groups of bones which it had formerly respected.
This mass of earth, penetrated by animal matter, indiscriminately envelopes the bones of all the species; and, if we except some found at the surface of the ground, and which had been transported there at much later periods, which may also be distinguished by their being much less decomposed, they must all have been interred in the same manner, and by the same causes. In this mass of earth there are found, confusedly mingled with the bones (at least in the cave of Gaylenreuth), pieces of a bluish marble, of which all the corners are rounded and blunted, and which appear to have been rolled. They singularly resemble those which form part of the osseous brecciæ of _Gibraltar_ and _Dalmatia_.
Lastly, what further conspires to render this phenomenon very striking, is, that the most remarkable of these bones are the same in these caverns, over an extent of more than two hundred leagues. Three-fourths and upwards belong to species of _bears_, which are now extinct. A half, or two-thirds of the remaining fourth, belong to a species of _hyena_, which is equally unknown at the present day. A smaller number belong to a species of the _tiger_ or _lion_ kind, and to another of the _wolf_ or _dog_ genus; lastly, the most diminutive have belonged to various small carnivora, as the _fox_, the _polecat_, or at least species very nearly allied to them, &c.
The Kirkdale Cavern, however, forms a notable exception, inasmuch as none, or very few, bones of bears are found in it, and in its being the hyena that appears to predominate among the carnivora.
The species so common in the alluvial formations, the _elephants_, _rhinoceroses_, _horses_, _oxen_ or _aurochs_, and _tapirs_, are of very rare occurrence in the caves of Germany. There are even some in which no one is said to have found them, and the only bones of herbivora mentioned are remains of deer. In this point also, however, the Kirkdale cave differs much from the others, inasmuch as it abounds almost as much in bones of large and small herbivora, as in bones of carnivora. All the great pachydermata of the alluvial formations are seen in it: the elephants, rhinoceroses and hippopotami. There are also seen in it bones of oxen, deer, and even small bones of mice and birds. But there are no bones of marine animals of any species, either at Kirkdale or in Germany. Those who have pretended that they saw bones of _seals_, _morses_, or other similar species, have been led into error by the hypothesis which they had previously adopted.
These bones of carnivora, so numerous in the caves, are rare in the great alluvial strata; the hyena alone has been seen in any quantity at Canstadt, near Aichstedt, and in some other places. There have also been found some traces of bears in Tuscany and Austria, but their relative proportion is always infinitely less than in the caves; and it is always sufficiently proved by these circumstances, that these various animals have lived together in the same countries, and have belonged to the same epoch.
Cuvier concludes, there can only be imagined three general causes which might have placed these bones in such quantity in these vast subterranean cavities. Either they are the remains of animals which inhabited these abodes, and which died peaceably there; or inundations and other violent causes have carried them into these cavities; or, lastly, they had been enveloped in rocky strata, the dissolution of which produced these caverns, and they have not been dissolved by the agent which carried off the matter of the strata.
This last cause is refuted by the fact, that the strata in which the caves occur contain no bones; and the second by the entireness of the smallest prominences of the bones, which does not permit us to think that they had been rolled; for if some bones are worn, as Mr Buckland has remarked, they are only so on one side, which would only prove that some current has passed over them, and in the deposit in which they are. We are, therefore, obliged to have recourse to the first supposition, whatever difficulties it presents on its part, and to say that these caves served as a retreat to carnivorous animals, and that these carried there, for the purpose of devouring them, the animals which formed their prey, or the parts of these animals.
Mr Buckland has observed, that the hyena bones are not less broken and splintered than those of the herbivorous animals; from which he concludes, that the hyenas had devoured the dead bodies of their own species, as those of the present day still do.
These animals attack each other during their life; for the fossil head of a hyena is preserved, which had evidently been wounded and afterwards healed[437].
This supposition is moreover confirmed by the animal nature of the earth in which these bones are found[438].
This much is certain, that the establishment of these animals in the caves has taken place at a much later epoch than that at which the great rocky strata have been formed, not only those which compose the mountains in which the caves are situated, but the strata of much newer origin. No permanent inundation has penetrated into the subterranean dens, and formed a regular rocky deposit. The mud arising from the proper decomposition of these animals, and the stalactites that have been filtered through the wall of the caves, are the only matters which cover these remains, and these stalactites increase so rapidly, that M. Goldfuss already found a layer of them covering the names of MM. Esper and Rosenmüller, whose visits did not date thirty years before his own. The rolled stones that are met with, and the marks of detrition observed on some bones, announce, at the very utmost, but passing currents.
But how have so many ferocious animals which peopled our forests been extirpated? All the reply we can make is, that they must have been destroyed at the same time, and by the same cause, as the large herbivora, which, like them, also peopled these forests, and of which no traces remain at the present day any more than of them.
ACCOUNT OF THE CAVE CONTAINING BONES AT ADELSBERG IN CARNIOLA.
The following interesting account of the cave, slightly noticed at pages 524 and 525, is extracted from a memoir by M. Bertrand Geslin, Member of the Natural History Society of Paris, published in the number of the _Annales des Sciences Naturelles_ for April 1826.
M. Cuvier, says Gesler, speaking of the Adelsberg Cave, from the account published by M. Volpi of Trieste, says, that it was nearly two leagues from the entrance where he discovered bones of animals.
Having visited this cave myself, I am obliged to say that M. Volpi’s assertion as to this matter is not very correct. On my way to Trieste, in July 1823, before going to Adelsberg, I had the advantage of seeing M. Volpi. In shewing me the bones collected by him at Adelsberg, he also assured me that they were found two leagues from the entrance of the cave, and only in a very compact block of several cubic feet, from which it was not possible to procure more, as he had taken all that he could easily remove.
Notwithstanding this discouraging account, I betook myself to Adelsberg, in order to see a sample of those immense caverns of secondary limestone. The entrance of the cave is situated in a white compact secondary limestone, lying in great beds inclined to the south-west, at an angle of from 30 to 35 degrees. At fifty paces from the entrance, we find ourselves as in a large apartment, which crosses the torrent of the Pinka. After passing to the left bank of this torrent, we enter a rather low and not long passage, which leads to a second apartment of an elongated form. It is here that the line of chambers truly commences. They are of large but variable dimensions, and are situated nearly upon a horizontal plane.
On entering this second chamber, I saw that the ground was formed of a yellow and reddish clayey mud, from one to two feet thick, and more or less impregnated and covered with crusts of yellow stalagmites. In the places where it offered little resistance, I dug it up with the point of my hammer, and was fortunate enough to disunite some fragments of bone, although, from what had been said to me, I ought not to have expected to find them. From this I was convinced, that if M. Volpi had only found bones at a distance of two leagues from the entrance, it was because he had not been at the trouble to search for them nearer. I fell to work with more ardour, and succeeded in digging up some in good preservation, such as radii, cubiti, femora, humeri, fragments of jaws, calcarea, toes, vertebræ, &c., belonging to bears of different sizes, of the species termed _Ursus spelæus_. It would appear that the hyena tribe is rather rare here, for I only procured a single bone belonging to it. It was particularly in two small lateral chambers, near the narrow passage, that I obtained a great quantity of these bones, the clay there having been dug up by the guides, in order to make the floor of the great apartment even with it.
I continued to dig as I advanced, and everywhere found bones more or less broken and enveloped in the clayey mud. After proceeding for half an hour, I fell in with a mass, in an apartment of considerable dimensions, which was of a conical form, and composed of blocks of compact white limestone, of all sizes, mixed with yellowish clayey mud. These blocks had their edges as sharp as if they had only been lately broken. The mass, which reached to the right wall of the cave, might be fifteen feet in height, and twenty in diameter at its base: it was covered with stalactite in several places. It was in this mass, at about ten feet above the floor of the cave, in the clayey mud that filled up the interstices between the blocks, that I found the entire skeleton of a young bear, in a space of two square feet at most. The bones which I dug out were the frontal part of the head, the lower jaw of the left side, the seventh cervical and eighth dorsal vertebræ; the eighth and fourteenth ribs of the right side; two tibia, femora, and cubiti, and two large canine teeth of another bear. If I could have raised up the limestone blocks, between which these bones lay, I might without doubt have procured a great part of this skeleton. There are still found here and there in the cave some small heaps of clayey mud, with fragments of white secondary limestone, as well as large isolated limestone blocks, which the guides are daily destroying, to make the floor even for the convenience of visitors.
I had only advanced an hour and a quarter’s progress into the cave, always finding bones, when the oil of my lamps beginning to fail, I was obliged to return without reaching the block in which M. Volpi had found the first bones. This block is without doubt owing to the same causes as the heap of which I have spoken above.
The manner in which these heaps exist, being composed of blocks of compact white secondary limestone, similar to that which forms the walls of the cave, with sharp edges, and piled upon each other, made me imagine that they might have fallen from the roof. As I returned, I examined the ceiling of the vaults with attention. As it was all covered over with stalactites, I could not discover any fissure.
From this short excursion in the Adelsberg cave, I am induced to believe, that the bones exist along the whole extent of the cave, and that they occur in two different ways; _1st_, scattered in the clayey mud which forms the floor of the chambers; and, _2dly_, buried in heaps formed of blocks of white secondary compact limestone, and yellow clayey mud.
The hypothesis which M. Cuvier admits as the most probable for explaining the presence of these bones in the caves, is that which would make these caves to have served as a retreat to carnivorous animals.
The presence of bones in the clayey mud of the floor of the Adelsberg cave accords well with this hypothesis; but the case is different with those which I found in the heaps of limestone blocks and clayey mud. The bones are not at the surface of the heap, but rather towards its middle part, buried among the blocks, and crushed by them. From this position, and the height at which the skeleton mentioned above occurs from the floor of the cave, it cannot be supposed that it formed part of the bones with which the bottom of the cave is strewed, nor that the blocks had fallen upon it. The bones contained in the heap in question must have been brought into their present position at the same time, and by the same cause as the limestone blocks. They could not, therefore, have belonged to animals which inhabited these caves, and died there peaceably.