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the district, and the residence of the governor. All this was owing to a hot-headed captain of volunteers taking it into his mind that I must needs be one of the two foreigners he had shortly before (such at least was the excuse made for him by the authorities, when called to account for such extraordinary conduct by the British ambassador at Madrid) received orders to search for, arrest, and send under a strong escort to Talarn to be shot! The governor, after examining my passport, and asking me a great many questions, of course set me at liberty; but, on my expressing my indignation at the brutal treatment to which I had been subjected, he had the audacity to tell me that I had no right to complain, for Spaniards were every bit as free as Englishmen, and the same thing might have happened to himself

, had he been travelling in England; and that, as I had stated my chief object, in wandering about the mountains, to be, to collect pieles and piedras (skins and stones), he really did not feel very much surprised at what had happened! Such an unknown species of biped is a naturalist in Spain.

Sept. 27. 1834.

ART. VII. Facts and Considerations on the Strata of Mont Blanc;

and on some Instances of Twisted Strata observable in Switzerland; by J. R. : with Remarks thereon, by the Rev. W. B. CLARKE, A.M. F.G.S. &c.

The granite ranges of Mont Blanc are as interesting to the geologist as they are to the painter. The granite is dark

red, often enclos-
70

ing veins of quartz,
crystallised

and
compact, and like-
wise well-formed
crystals of schorl.
The average ele-
vation of its range
of peaks, which ex-
tends from Mont
Blanc to the Tête
Noire, is about
12,000 English feet
above the level of
the sea. [Its high-

culminating

point is 15,744 feet.] The Aiguille de Servoz (fig. 70.), and that of Dru

[graphic]

est

(fig. 71.), are excellent examples of the pyramidal and splintery formation which these granite ranges in general 71

assume. They rise

out of immense de fields of snow; but,

being themselves too steep for snow to rest upon, form red, bare, and inaccessible peaks, which even the chamois scarcely dares to climb. Their bases appear sometimes abutted against (if I may so speak) by mica slate, which forms the south-east side of the Valley of Chamonix; whose

flanks, if intersected, might appear as in fig. 72. a, Granite, forming on the one side (B) the Mont Blanc, on the other (c) the Mont Breven;

b, mica slate resting 72

on the base of Mont Blanc, and which contains amianthus and quartz, in which capillary crystals of tita

nium occur; c, calcareous rock; d, alluvium, forming the Valley of Chamonix. I should have mentioned that the granite appears to contain a small quantity of gold, as that metal is found among the granite debris and siliceous sand of the river Arve' [Bakewell, i. 375.); and I have two or three specimens in which chlorite (both compact and in minute crystals) occupies the place of mica. — J. R. March, 1834.

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[REMARKS, obligingly added by the Rev. W. B. Clarke, to whom we had submitted J. Ri's Notes.]

The granites of the Mont Blanc have already been ably described by various geologists; as Saussure, De Luc, the writer in Ebel, Mr. Bakewell, &c. The latter author has given a coloured view of the Aiguille de Dru as a frontispiece to

vol. ii. of his Travels in the Tarentaise ; and a description of the rocks, ii. 12. The granite is not always a “dark red,” for the glaciers are strewed with blocks and fragments of differently coloured granites; and, among others, with the peculiar white granite from the summits of the Aiguilles and of the Mont Blanc, which are, perhaps, the most common. This granite is traceable by its character, and may be picked up at the edge of the ice on Montanvert, as well as all along the route of its transport, as far as the Jura. See Bakewell, vol. i. p. 375-6.* J. R.'s sketches give a good idea of the pyramidal forms of the aiguilles. There is a large lithographic plate of Mont Blanc, taken from Servoz, by Villeneuve, which is worth the purchasing, if it fall in the way of a collector. It gives the whole range from Chamonix, with the intermediate mountains, and the vale between it and Servoz.+ Mr. Charles Fellows, a fel

[This state of alpine strata has given rise to the two following comprehensive speculations. They scarcely consort enough with the present subject to be very fitly attached here; but they cannot fail to excite welcomely the imagination of the general reader. On this account we hope that neither Mr. Clarke nor J. R. will disapprove our attachment of them.

“ Those naturalists who have seen the glaciers of Savoy, and who have beheld the prodigious magnitude of some fragments conveyed by them from the higher regions of Mont Blanc to the valleys below, to a distance of many leagues, will be prepared to appreciate the effects which a series of earthquakes might produce in this region, if the peaks, or 'needles' as they are called, of Mont Blanc were shaken as rudely as many parts of the Andes have been in our times." -Lyell's Principles of Geology, vol. iii.

“ The rapid change which is now going on in the greatest altitudes of Switzerland, points out to us the mode in which nature is operating by decomposition, and the attraction of gravitation. When standing on the borders of the Mer de Glace, and while crossing its frozen bosom, this operation was brought most forcibly to my mind. Every moment my ears were saluted with the sound, more or less distant, of rocks precipitated from some height into the abysses below, and which reverberated over this frozen sea. The time may come when the pinnacles of Mont Blanc and other mountains which surround the beautiful valley of Chamouni, will have been precipitated to their bases, and the debris be so completely carried off as to leave, perhaps, that beautiful and fertile spot itself, the highest pinnacle of the country, a naked rock to be gazed at from a distance.”

Lea's Contributions to Geology (Philadelphia, 1833), Introd. p. 16, 17.]

+ The allusion to the Valley of Chamonix recalls to my mind that splendid and beautiful poem, upon which alone the lately deceased Mr. Coleridge might have rested his fame as one of the greatest of our modern bards. There is nothing, if we except Milton, in the whole range of English blank verse, at all comparable with the Hymn whence the following extract is made :

“ Ye Ice falls ! ye that from the mountain's brow

Adown enormous ravines slope amain –
Torrents, methinks, that heard a mighty Voice,

low-traveller of mine (who, in 1827, ascended Mont Blanc), has given, in his Narrative of the Ascent, a good view of it, with the glaciers and aiguilles, as taken from the Breven with a camera obscura; and also another from the Col de Balme; both of these convey a perfect idea of the perpendicularity of the stratification, though the former is out of proportion. Mr. De la Beche has the best view from the Breven, in his Sections and Views. Mr. Hawes, who ascended with Mr. Fellows, thinks Mr. Fellows's drawings rather too imaginative; and I think so too. The same remarks apply to Mr. Auldjo’s views. J. R.'s sketches (figs. 70, 71.) are illustrative; and are, therefore, though not novel, worth preserving.

The granite of Mont Blanc is said to contain gold. Gold is very common in all soils and in most river beds; though in quantity too minute to be observable. It is universally distributed, and may be procured from decayed vegetable matter. It is obtained in small quantities near Simplon, on the route of that name: most alluvial deposits have traces of it. See the localities and river beds named by Leonhard and Phillips and Jameson. The washing of the sand of the Rhine at Baden produced, in 1827, 2317 kr. 531 gr. of gold; from 1828 to 1829, 2999 kr. 441} gr. (Allgemeine Handlung Zeitung, Oct. 1829.) Gold is also found in the rivers of the north of Moldavia ; in the Goldbach near Audel, in Trèves ; near Endkirch on the Moselle ; and in the Guldenbach near Stromberg, in the neighbourhood of Coblentz. (Gruithuisen, Analekten für Erd und Himmels-kunde, part iii. p. 36.)

The chloritic granite, of which J. Ř. has spoken, comes from the Col de Géant: the red granite from the Aiguille de Blaittière. A far more striking discovery would be that of sulphur in the granite, which has been, in some cases, found. -W. B. Clarke.

And stopp'd at once amidst their maddest plunge –
Motionless torrents! silent cataracts!
Who made you glorious as the gates of Heaven
Beneath the keen full Moon? Who bade the Sun
Clothe you with rainbows? Who, with living flowers
Of loveliest blue *, spread garlands at your feet?
God! let the torrents like a shout of nations
Answer! and let the ice plains echo, God!
God! sing ye meadow streams with gladsome voice!
Ye pine groves, with your soft and soul-like sounds!
And they, too, have a voice, yon piles of snow,
And in their perilous fall shall thunder - God!

Hymn before Sunrise in the Vale of Chamonix. Gentiàna major [? acaúlis), which grows on the very edge of the ice. (See p. 249.)

Twisted STRATA. - The contortions of the limestone at the fall of the Nant d’Arpenaz, on the road from Geneva to Chamonix, are somewhat remarkable. [See fig. 75. in p. 651.] The rock is a hard dark brown limestone, forming part of a range of secondary cliffs, which rise from 500 ft. to 1000 ft. above the defile which they border. The fall itself is about 800 ft. high. The strata bend very regularly; except (at e and f), where they appear to have been fractured.-J. R. March, 1834. [.J. R. sent with this communication a small neat copy of a sketch carefully taken on the spot; but as this did not exbibit the stratification so distinctly as one which the Rev. W. B. Clarke has since supplied ( fig. 75.), we have only engraved the latter; into which we have endeavoured to introduce the letters e and f, in the points in which J. R. had, in his own sketch, exhibited them. The following remarks are by Mr. Clarke.)

Nant * d'Arpenaz. - J. R.'s drawing is too indistinct to give an idea of the stratification. The curvature of the strata is a disputed point. Saussure first stated the circumstance; subsequently, Mr. Bakewell has considered the appearances an illusion produced by the cleavage. I am compelled to differ from him, and to adhere to Saussure; who mentions that the strata, being originally horizontal, are bent upwards, and then curved backwards. (See Bakewell's Travels, vol. i. p. 339.) In the year 1825, I spent two days, in July, in examining the whole of the strata on both sides of the Nant d’Arpenaz, and, in fact, all that side of the Valley of Maglanz from Cluse to St. Martin ; and I confess that there are so many instances of contorted and perpendicular strata in the limestone, that I came to the conclusion that the rocks at Arpenaz, as well as at Nant d'Orli, are merely portions of a great range of strata, which, owing to vast pressure and elevation of the subjacent beds, have been forced out of their horizontal position. The falls, in both instances, rush over the face of the rock; where there is, evidently, a fissure, apparently caused by a crack upwards through the cliffs. The real curves in the beds are explained in the appended diagrams, which were made in 1825.

* Nant, in the language of the country, means a waterfall.

+ The following passage is also corroborative of Saussure's opinion upon the subject :-“ Ein schönes vielfaches Echo empfängt hier den Reisenden ; weiterhin stürzt ihm zur Seite von einer Höhe von 800 Fuss der Gebirgstrom Arpenas (Nant d’Arpenaz) als Wasserfall herab, der auch bei geringerer Wasserfülle eins der sonderbarsten Schauspiele giebt, weil die gewaltige Felsenmasse, über die er hinabstürzt, eine concentrische Schichtenbildung hat, die auf das deutlichste in die Augen springt, wie Schaalen, die sich um einen gemeinsamen Kern aufsetzen, und zu bedeutender Höhe in S-förmiger Gestalt sich emporwinden.” (Ritter's Beschreibung zu Kummer's Stereorama des Montblanc-Gebirges, Berlin, 1824, p. 31.)

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