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tirement among a beloved family. The pains of the gout alone sometimes interrupted his tranquillity, and caused him the greatest of his disappointments, by preventing him from going regularly, as he had been accustomed, to hear his fellow-members at the Academy, for there he was as constant as he was silent. In his family he was as modest and mild as in the world.

At length he slept the sleep of the just, on the 19th February 1816; aged somewhat less than 86 years. A son, one of his most distinguished pupils, and inspector-general of the mines, revives his name in the career on which he first entered, and in which this son has already made not less remarkable progress than his father.

Observations in Answer to a Memoir by Messrs Sedgwick and · Murchison on the Austrian Alps *. By Ami BOUE, M. D.

F. G. S. M. W. S. &c. &c. Communicated by the Author.

In the memoir of the two active members of the Geological Society of London, we were pleased to observe, that they had described and classified the various alpine deposites nearly in the order which we pointed out in our papers in the Edinburgh New Philosophical Journal for 1830, and in the Zeitschrift für Mineralogie von Leonhard, for 1829, and in the Journal de Geologie, Nos. I. & II. for 1830. Nevertheless, they have omitted some parts of the geological history of the Alps; or, at least, they hardly notice some of the prominent subdivisions of these forinations, which certainly would not have escaped them had they allowed themselves sufficient time to take a more extensive view of that immense chain. As we are of opinion that the structure of the calcareous arenacevus chain of the Northern Alps presents peculiarities unknown on the southern side of the Alps, we could have wished that the authors in question had separated entirely the descriptions of each of these chains, because the intermixture of local details, sometimes from the one side, sometimes from the other side, are apt to deceive the reader, and induce him to believe that if a complete identity does

• The memoir appeared in the Annals of Philosophy for August 1830.

not exist, yet that there reigns a great similarity between the succession of the southern and northern alpine deposites. It has been long known, that, in Carinthia, especially near to Bleiberg, true transition rocks, even with their characteristic fossil shells, make their appearance. Our authors have added new. and interesting details to those already known, in regard to this isolated occurrence among the Alps, and excite the wish that these ancient rocks may be farther traced, with the view of ascertaining whether or not they do not actually extend under the secondary rocks, in the direction of Idria. Now, as these rocks are entirely unknown along the whole of the northern alpine chain, from the Mediterranean Sea to the Carpathians, and as they do not occur in the Italian Alps, it would have been better to have presented this fact as an isolated accident, rather than endeavour to join these rocks with other calm careous and arenaceous rocks, without, or nearly without, organic remains, which some may be disposed to call transition, while others will refer them to the secondary class. Besides, if these crystalline masses, containing encrinal beds, described as occurring on the northern side, are truly transition, certainly their characters differ from those of the rocks of Carinthia, containing shells. On the other hand, we see the term greywacke applied to rocks on the northern side of the Alps, which make a transition from the micaceous or chloritose quartzose rocks, to others with a still more arenaceous character. We confess that these last mentioned conglomerated masses cannot be compared with, or referred to, the greywacke of the Hartz or the south of Scotland, but to us appear mere varieties of quartzose' talcose rocks, deposites also well known in Scotland, which are, in our opinion, less affected and altered by igneous agents than the other primary, but formerly arenaceous rocks.

After these general observations on our authors' mode of treating the subject, we shall now take the liberty of examining the divisions which they propose. They distinguish, in the Alps, 1. With all geologists, a central primary axis. 2. Crystalline. rocks, with limestone beds, containing few organic rea mains, the system graduating into rocks agreeing with the ordinary transition type. 3. Red marl, sandstone, gypsum, &c. containing, in parts of their range, large subordinate masses of

Alps, 1. With all limestone beds, conta aoreeing with

magnesian limestone. 4. Older alpine limestone. 5. Alpine limestone, with subordinate saliferous deposites. 6. Younger alpine limestone. 7. Tertiary formations.

In regard to the central primary axis, we have but one remark to make, viz. that its termination is not distinctly given by our authors. The primary Alps, that appear to sink out of sight between Wien-Neustadt and Oedenburg, in Hungary, actually continue under the tertiary soil, and the valley of the Danube, and crop out again in the Neitra Comitat, to the east and west of that town. From this point, they extend to the NW. and NE. of Neusohl; and, lastly, they unite with the chain of Prassiva, Kralova, Hola, &c. The granitic group north of Presburg, as that of the Tatra, are only isolated portions of this chain. The central alpine chain would thus terminate geographically near to Vienna, but geologically in Northern Hungary. It is separated from the Carpathian primary chain, either because one part may not have been elevated to the same height as the rest, or because a partial sinking down has buried that portion. On the other hand, the primary chains of the Marmarosh and Transylvania, are evidently not in the same direction as the similar Alpine chain, and owe their origin to upheavings that have taken place in totally different lines of direction.

This is the opportunity to defend myself against a reproach of Messrs Murchison and Sedgwick. They accuse me of pushing the spirit of generalization too far, of bringing under comparison formations widely separated from each other in the Alpine and Carpathian chains, sometimes by the help of mineralogical characters, and almost unassisted by a single organic remain. If I am not mistaken, we might retort, and with more justice, on these gentlemen, when we find them intermingling the geology of Carinthia and Salzburg ; but our defence will not rest on such criticisms. We have already proved, that the primary Alpine chains do continue in the northern Carpathians; and hence it is quite natural to expect in these last named mountains also, the continuation of the Alpine calcareous chain. This last fact is generally acknowledged ; and I doubt not if these gentlemen had visited the Carpathians, they would have been the first to assent to it. It is to be understood that we do. not mean to say that small calcareous deposites are placed along

the primary Carpathian chain ; for this is by no means the fact; but we repeat it, that, as in the Alps, from Vienna and Presburg, to the east of the Tatra, there is an uninterrupted calcareous band, which is often separated from the primary hills by a system of reddish arenaceous rocks. Besides, this alpine limestone is not much covered by more recent calcareous deposites, nor has it been so much thrown up, as to shew, as in the Alps, its whole body, and to allow us to see, in this calcareous chain, also the subordinate arenaceous beds or masses.

Our adversaries seem to imagine, not only that all our opinions in regard to the Carpathians are more fanciful than correct, but they also appear to insinuate, that we may have mistaken for alpine limestone some other calcareous deposite, which we could only have examined in a few spots, and that we afterwards united the whole according to our fancy. Happily, however, our map of the north-east part of Hungary, presented last April to the Geological Society of London, affords proofs of our local observations, united with those of Messrs Lill and Beudant, and which can at any time be verified. The calcareous alpine zone, which is coloured on the map, exists really in nature, and extends uninterruptedly from Vienna to Tatra. Every one will be able, on inspecting a good map, to see that the numerous localities where we studied the formation, and which we shall enumerate, were sufficient to allow us, even without the aid of organic remains, to decide that alpine limestone exists equally in Tatra as in the Alps. If it is ever allowable to make use of the witticism of Mohs, viz. that, as we cannot determine the species or genus of a tree from the birds that sit on it, consequently fossils cannot shew the age of a deposite, which must be determined by position and mineral contents, it is in this case. Indeed, if there be a continuation of the limestone ridges of the Alps and that of the T'atra, what necessity is there for taking into consideration the fossil organic remains ? even if Trilobites occur in the Tatra alpine limestone, and Bacculites in that of Vienna, if both rocks form one single continuous mass, if they have the same position, they, in our opinion, are of the same age. Now, the Vienna or Baden alpine limestone reappears on the eastern side of the tertiary plain of that city, viz. at the distance of six or eight miles,

OCTOBER-DECEMBER 1830.

at Wimpassing, afterwards between Teusch-Altenberg, Edelsthal, and Hainburg, from where it crosses the Danube to Theben, and, lying along the granitic ridge, it is found again at Ballenstein, at Borostyanko, at Pernek, at Breitenbrunn, at Blasenstein, Elesko, and to the east of Hradystie. From that village, and from Nadas, it extends to Csejta and Neustadt, upon the borders of the Wag near Bohuslariez, around Beczko and Trentschin, at Orecho, Sztrezezenitz, and between Hrabooka and Pucho. It forms the highest hills between the valleys of the Wag and the Nyitra, and is covered partly by secondary and tertiary rocks, a fact well known from the observations of Beudant, and confirmed by those of Lill. After having followed this formation, step by step, we had still an opportunity of studying it more to the north at Preeven, Illova, Warin, Bela, and Tyrhova. We saw it also extending behind Kubin, Chlebna, and Habowka ; and a branch terminates on the northern side of the Tatra, from the west of Koscielisko to Zifjar; in the mean time another unites itself with the limestone south of the Tatra, and of the superior valley of the Wag, and extends to Newsohl, where we saw it on a former tour, and where others have described it. .

It is true that, in this extensive calcareous chain, we observed fossil organie remains only between Warin and Tishova, around the Tatra, and in the country of Neusohl; but the same is the case with the Austrian Alps ; and the magnesian rocks, full of small rents, seem far less favourable to the preservation of petri. factions than the complete dolomites. On the other hand, these fossils correspond with those of the limestone of the Alps, being belemnites, certain ammonites, certain smooth or folded terebratulites, encrinites, and zoophytes. In this way we have the identity and continuance of the same formation with the same fossils, and that from Vienna to the Tatra. Now, we ask (Mr Lill and I), are not we entitled to compare some sections of the Carpathian limestone ridge with others taken among the calcareous alpine chain, and to use in this way Carpathian localities, or sections where the strata have been but slightly deranged, to clear up in the Alps the nature of tracts, where great catastrophes or upheavings have disturbed and confused the true series of deposites ? The answer to our question cannot be

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