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GLACIER

Online Encyclopedia
Originally appearing in Volume V01, Page 754 of the 1911 Encyclopedia Britannica.
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GLACIER. As to Alpine legends, consult Maria Savi-Lopez, Leggende delle Alpi (1889); M. Tscheinen, Walliser-Sagen (1872); Th. Vernaleken, Alpensagen (1858); and I. V. Zingerle, Sagen aus Tirol (1859); and as to Alpine poetry—J. Adam, Der Natursinn in der deutschen Dichtung (1906); E. A. Baker and F. E. Ross, The Voice of the Mountains (1905, an anthology in verse and prose); A. von Haller, Die Alpen (1732, best ed., 1882, illustrated ed., 1902) ; and H. E. Jenny, Die Alpendichtung in der deutschen Schweiz (1905). As to Alpine dialects, consult J. Alton, Die ladinischen Idiome in Ladinien, Groden, Fassa, Buchenstein, Ampezzo (1879); J. A. Chabrand and A. de Roches d'Aiglun, Patois des Alpes cottiennes (1877); Z. and E. Pallioppi, Dizionari dels Idioms Romauntschs d'Engiadina ota e bassa, &c. (1895); A. Socin, Schriftsprache and Dialekle im Deutschen (1888); F. J. Stalder, Die Landessprachen der Schweiz (1819), and J. Zimmerli, Die deutsch franzosische Sprachgrenze in der Schweiz (3 vols., 1891–1899) ; besides the great Swiss Dialect Dictionary (Schweiz. Idiotikon) in course of publication since 1881. As to the history of the Alps, the following works touch on various aspects of the subject :—G. Allais, Le Alpi Occidentali nell' Antichita (1891) ; \V. Brockedon, Illustrations of the Passes of the Alps (2 vols., 1828–1829) ; J. Grand-Carteret, La Montagne a travers les ages (2 vols., 1902–1904) ; G. Oberziner, Le Guerre di Augusta contra i populi alpini (1900); E. Oehlmann, Die Alpenpdsse im Mittelalter(1878–1879); R. Reinhard, Passe and Strassen in den Schweizer Alpen (1903); and L. Vaccarone, Le Vie delle Alpi Occidentali negli antichi tempi (1884) ; while W. A. B. Coolidge's Josias Simler et les origines de l'alpinisme jusqu'en 1600 (1904) summarises our know-ledge of the Alps up to 1600. Among works of a more or less descriptive nature (based on actual travels), the following list includes all the standard works dated before 1855 :—Le Alpi the cingono l'Italia (1845); J. G. Altmann, Versuch einer hist. u. phys. Beschreihung der helvetischen Eisbergen (1751); A. C. Bordier, Voyage pittoresque aux glacieres de Savoye (1773); P. T. de Bourcet, Memoires militaires sur les frontieres de la France, du Piemont, et de la Savoie (180,) ; M. T. Bourrit, Description des glacieres, glaciers, et amas de glace du duche de Savoye (,773, Eng. trans., 1775), Description des Alpes Pennines et rhetiennes (2 vols., 1781, 3rd vol., 1785), and Description des cols ou passages des Alpes (2 vols., 18o3); W. Brockedon, Journals of Excursions in the Alps (1833); U. Campell, Raetiae alpestris topegraphica descriptio (finished in 1572, but publ. only in 1884, with a supplement in 1900) ; J. A. Deluc and P. G. Dentan, Relation de differenis voyages' dans les Alpes du Faucigny (1776); E. Desor, Excursions et sejours dans les glaciers (2 series, 1844–1845) ; C. M. Engelhardt, Naturschilderungen aus den hochsten Schweizer-Alpen (184o), and Das Monte-Rosa and Matterhorn-Gebirg (1852); J. D. Forbes, Travels through the Alps of Savoy (1843, new ed., 1900); Sir John Forbes, A Physician's Holiday (1849) ; J. FrSbel, Reise in die weniger bekannten Thaler auf der Nordseite der penninischen Alpen (184o) ; G. Gnifetti, Nozioni topografiche del Monte Rosa ed ascensioni su di esso (1845, 2nd ed., 1858); G. S. Gruner, Die Eisgebirge des Schweizerlandes (3 vols., 176o) ; J. Hegetschweiler, Reisen in den Gebirgsstock zwischen Glarus and Graubunden, 1819–1822 (1825);' G. Hoffmann, Wanderungen in der Gletscherwelt (1843); F. J..Hugi, Naturhistorische Alpenreise (183o); C. J. Latrobe, The Alpenstock (1829) and The Pedestrian (1832); J. R. and H. Meyer, Reise auf den Jungfrau-Gletscher and Ersteigung seines Gipfels (1811) ; De Montannel, La Topographic militaire de la frontiere des Alpes (written in 1777, but publ. in 1875 only) ; Operations geodesiques et astronomiques pour la mesure d'un arc du parallele moyen (2vols., 1825–1827) ; H. R. Rebmann, Ein poetisch Gastmal and Gesprach zweyer Bergen, nemlich des Niesens and Stockhorns (1606);' C. Rohrdorf, Reise fiber die Grindelwald-Viescher-Gletscher and Ersteigung des Gletschers des Jungfrau-Berges (1828); H. B. de Saussure, Voyages dons les Alpes (4 vols., 1779–1796) ; A. Schaubach, Deutsche Alpen (4 vols., 1845-1847) ; J. J. Scheuchzer, Helvetiae Stoicheiographia, Orographia, it Oreographia (1716), and Itinera per Helvetiae alpinas regiones facia annis 1702–1711 (4 vols., 1723) ; J. Simler, Vallesiae Descriptio it de Alpibus Commentarius (1574, new ed. in 1904, see Coolidge above) ; Albert Smith, The Story of Mont Blanc (1853); G. Studer, Topographische Mitteilungen aus dem Alpengebirge (1843); R. Tapffer, Voyages en zigzag (2 series, 1844 and 1853); Aegid. Tschudi, De prised ac vend alpina Rhaetid (1538, also in German, same date) ; and L. von Welden, Der Monte Rosa (1824). As to works published alter 1855 we can only give a short, though carefully selected, list. C. Aeby and others, Das Hochgebirge von Grindelwald (1865) ; W. A. Baillie-Grohmann, Tyrol and the Tyrolese (1876), and Gaddings with a Primitive People (2 vols., 1878) ; H. von Barth, Aus den nordlichen Kalkalpen (1874); L. Barth and L. Pfaundler, Die Stubaiergebirgsgruppe (1865); G. F. Browne, Off the Mill (1895); Mrs H. W. Cole, A Lady's Tour round Monte Rosa (1859); E. T. Coleman, Scenes from the Snow Fields (1859); Sir Martin Conway, The Alps from End to End (1895); A. Daudet, Tartarin sur les Alpes (1885, Eng. trans., same date)); C. T. Dent, Above the Snow Line (1885) ; Miss A. B. Edwards, Untrodden Peaks and Unfrequented Valleys (1873, Dolomites) ; Max Forderreuther, Die Allgauer Alpen (1906); D. W. Freshfield, Across Country from Thonon to Trent (1865), and Italian Alps (1875); Mrs Henry Fresh-field, Alpine Byways (1861), and A Summer Tour in the Grisons (1862) ; H. B. George, The Oberland and its Glaciers (1866) ; J. Gilbert and G. C. Churchill, The Dolomite Mountains (1864); A. G. Girdlestone, The High Alps without Guides (187o) ; P. Grohmann, Wanderungen in den Dolomiten (1877); P. Gusafeldt, In den Hochalpen (1886), and Der Montblanc (1894); T. W. Hinchliff, Summer Months among the Alps (1857) ; C. Hudson and E. S. Kennedy, Where there's a Will there's a Way (1856) ; E. Javelle, Souvenirs d' un Alpinisie (1886, Eng. trans., 1899); S. W. King, The Italian Valleys of the Pennine Alps (1858) ; Le Valli di Lanzo (publ. by the Italian Alpine Club in 1899) ; A. Lorria and E. A. Martel, Le Massif de la Bernina (1894); J. Michelet, La Montagne (1868, Eng. trans., 1872); A. W. Moore, The Alps in 1864 (1867, publ. ed., 1902); A. F. Mummery, My Climbs in the Alps (1895); Norman-Neruda, The Climbs of (1899) ;.. Peaks, Passes and Glaciers (3 vols., 1859–1862) ; L. Purtscheller, Uber Fels and Firn (1901); E. Rambert. Ascensions it fldneries (2 vols., 1888) ; G. Rey, Il Monte Cervino (1904) ; John Ruskin, vol. iv. (On Mountain Beauty) of Modern Painters (1856); A. von Ruthner, Aus den Tauern (1864) and Aus Tirol (1869); V. Sella and D. Vallino, Monte Rosa e Gressoney (189o) ; F. Simony, Das Dachsteingebiet 0889–1896); L. Sinigaglia, Climbing Reminiscences of the Dolomites (1896); K. von Sonklar, Die Oetzthaler Gebirgsgruppe (186o), and Die Gebirgsgruppe der Hohen-Tauern (1866) ; Sir L. Stephen, The Playground of Europe (1871) ; B. Studer, Geschichte der physischen Geographie der Schweiz bis 1815 (1863); G. Studer and others, Berg- and Gletscherfahrten (2 series, 1859 and 1863); G. Theobald, Naturbilder aus den rhatischen Alpen (186o), and Das Biindner Oberland (1861); F. F. Tuckett, Hochalpenstudien (2 vols., 1873–1874) ; Miss L. Tuckett, How we Spent the Summer (1864), Pictures in Tyrol (1867), and Zigzagging amongst Dolomites (1871); J. Tyndall, The Glaciers of the Alps (186o), Mountaineering in 1861 (1862), and Hours of Exercise in the Alps (1871); J. J. Weilenmann, Aus der Firnenwelt (3 vols., 1872–187i); E. Whymper, Scrambles amongst the Alps (1871); Sir A. Wills, Wanderings among the High Alps (1856), and The " Eagle's Nest " in the Valley of Sixt (186o) ; G. Yeld, Scrambles in the Eastern Graians (1900) ; H. Zschokke, Reise auf die Eisgebirge des Kantons Bern and Ersteigung ihrer hochsten Gipfel im Sommer von 1812 (1813); E. Zsigmondy, lm Hockgebirge (1889); M. Zurbriggen, From the Alps to the Andes (1899). Many useful practical hints as to climbing are to be found in C. T. Dent and others, Mountaineering (1892, 3rd ed., 1900, " Badminton Library ") ; the Manuel d'Alpinisme (1904, publ. by the French Alpine Club) ; J. Meurer, Handbuch der alpinen Sport (1882), Katechismus fur Bergsteiger (1892), and Der Bergsteiger im Hochgebirge (1893); and C. Wilson, Mountaineering (1893, " All England " series). As regards the dangers of Alpine climbing consult C. Fiorio and C. Ratti, I Pericoli dell' Alpinismo (1889), and E. Zsigmondy, Die Gefahren der Alpen (1885, Fr. trans., 1889). There are also special guide-books for the use of clitnbers in the Alps—the " Climbers' Guides " series, edited by Sir Martin Conway and W. A. B. Coolidge (lo vols., 1890–1904); W. A. B. Coolidge, H. Duhamel and F. Perrin, Guide du Haut Dauphine (1887, with supplement in 189o, Eng. trans., 1892 and 1905); L. Purtscheller and H. Hess, Der Hochtourist in den Ostalpen (2 vols., 1894, 3 vols., 3rd ed., 1903) ; the 3 vols. publ. (1902–1905) by the Swiss Alpine Club under the name of Clubfiihrer to the Alps of Glarus and Uri, and V. Wolf von Glanvell, Dolomitenfuhrer (1898). As regards the early history of Alpine exploration consult W. A. B. Coolidge, Josias Simler et les origines de l'alpinisme jusqu'en 1600 (1904), and F. Gribble, The Early Mountaineers (1899). For the later period see, besides the more general works of travel mentioned above, the publications (that date from 1863) of the various Alpine Clubs—the Alpine Journal (English A. C.), theAnnuaire, Bulletin, La Montague, and Revue alpine (French A. C.), the Jahrbuch, Mitteilungen, Verhandlungen, and Zeitschrift (German and Austrian A. C.), the Alpinista, Bollettino, and Rivista Mensile (Italian A. C.), and the Alpina, Echo des Alpes, Jahrbuch, Schweizer Alpen-Zeitung (Swiss A. C.), besides those of the smaller societies, such as the Osterreichische Alpen-Zeitung (Austrian A. C.), the Annuaire (Societe des Touristes du Dauphine), and the Annuario (Societa degli Alpinisti Tridentini). Summaries of the Alpine history of the three great divisions of the Alps are given in (W. Alps) L. Vaccarone, Statistica delle Prime Ascensioni nelle Alpi Occidentali (3rd. ed., 189o—this work omits the Dauphine Alps, as to which see the 1887 work or its Eng. version, 1905, mentioned above) ; (Central and Swiss Alps) G. Studer, Ube?. Eis and Schnee (2nd ed. 3 vols., 1896–1899) ; and (E. Alps) G. Groger and J. Rabl, Die Entwickelung der Hochtouristik in den bsterreichischen Alpen (189o), and E. Richter, Die Erschliessung der Ostalpen (3 vols., 1894). The detailed history of Mont Blanc has been written by Ch. Durier, Le Mont Blanc (1877, 4th ed., 1897), and C. E. Mathews, The Annals of Mont Blanc (1898). Lives of some of the most celebrated mountain guides have been written in C. D. Cunningham and W. de W. Abney, Pioneers of the Alps (2nd ed., 1888). (2) Maps.—There is no good modern and fairly large-scale map of the entire chain of the Alps. But L. Ravenstein's maps (scale 1 :250,000) of the Swiss Alps (2 sheets) and of the Eastern Alps (8 sheets) include the whole chain, save that portion south of the range of Mont Blanc. All the countries which include Alpine districts have now issued official Government maps. The French map on a scale of I :80,000 is clearer and more accurate than that on a scale of 1: Ioo,000. The Italian Government has published maps on scales of 1:50,000 and i : 100,000, the Austrian on a scale of I : 75,000, and the Bavarian on a scale of i : 5o,000. But the most splendid Government map of all is that put forth by the Swiss Federal Topographical Bureau, under the title of Siegfried Atlas (scale 1 :5o,00o for the Alpine districts), which has quite superseded the Dufour Map (scale I : Ioo,000), the history of which was published in 1896. For maps of the Swiss Alps and their neighbours, see J. H. Graf, Literatur der Landesvermessung (1896, with a supplement). A few of the best special maps of certain districts may be mentioned—such as H. Duhamel's maps of the Dauphine Alps (4 sheets on a scale of I :i oo,000, 1889, 2nd ed., 1892), and that of the range of Mont Blanc (scale 1 :50,000, 1896, 2nd ed., 1905), by X. Imfeld and L. Kurz. The German and Austrian Alpine Club is publishing a very fine set of maps (scale I :50,000) of the Eastern Alps, which are clearer and better than the Austrian Government's Topographische Detailkarten (II sheets, scale 1 : 50,000). (W. A. B. C.) ro. Geology.—The Alps form but a small portion of a great zone of crumpling which stretches, in a series of curves, from the Atlas Mountains to the Himalayas. Within this zone thecrust of the earth has been ridged up into a complex system of creases or folds, out of which the great mountain chains of southern Europe and Asia have been carved by atmospheric agencies. Superficially, the continuity of the zone is broken at intervals by gaps of greater or less extent; but these are due, in part at least, to the subsidence of portions of the folded belt and their subsequent burial by more recent accumulations. Such a gap is that between the Alps and the Carpathians, but a glance at a geological map of the region will show that the folding was probably at one time continuous. Leaving, however, the larger question of the connexion between the great mountain ranges of Europe and Asia, we find that the Alps are formed cf a series of wrinkles or folds, one behind another, frequently arranged en echelon. The folds run, in general, in the direction of the chain, and together they form an arc around the plain of Lombardy and Piedmont. Outside this arc lies a depression along which the waters of the upper Danube and the lower Rhone find their way towards the sea; and beyond the the ancient crystalline masses of Bohemia, the Black Forest and the central plateau of France, together with the intervening Mesozoic beds of southern Germany and the Jura. The depression is filled by Miocene and later beds, which for the most part lie flat and undisturbed as they were laid down. Beyond the depression also, excepting in the Jura Mountains, there is no sign of the folding which has raised the Alpine chain. Some of the older beds indeed are crumpled, but the folding is altogether different in age and in direction from that of the Alps. To assist in forming a clear idea of the relations of the Alps to the surrounding regions, a simple illustration will suffice. Upon a table covered by a cloth lay two books in the relative positions shown in figure. The book A represents the central plateau of France and the book B represents the' rocks of Bohemia and southern Germany. If the two hands be placed flat upon the table, in the angle between the two books, and the cloth pushed towards the corner, it will at once be rucked up into a fold which will follow a curve not unlike that of the Alps. The precise character and form of the folds produced will depend upon the nature of the cloth and other accidental circum- FIG. 1.—Looking down stances;, but with a little adjustment on the table. not only a representation of the chain of the Alps, but even a subsidiary fold in front in the position of the Jura Mountains may be obtained. Imperfect though this illustration may be, it will serve to explain the modern conception of the forces concerned in the formation of the Alps. Within she crust of the earth, whether by the contraction of the interior or in any other way, tangential pressures were set up. Since the crust is not of uniform strength through-out, only the weaker portions yielded to the pressure; and these were crumpled up against the more resisting portions and sometimes were pushed over them. In the case of the Alps it seems natural enough that the crystalline masses of Bohemia, the Black Forest and the central plateau of France should be firmer than the more modern sedimentary deposits; but it is not so easy to understand why the Mesozoic rocks of southern Germany resisted the folding, while those of the Jura yielded. It should, however, be borne in mind that the resisting mass is not necessarily at the surface. Such is in outline the process by which the Alps were elevated; but when the chain is examined in detail, it is found that its history has not been uniform through-out; and it will be convenient, for purposes of description, to divide it into three portions, which may be called the Eastern Alps, the Swiss Alps, and the Western Alps. The Eastern Alps consist of a central mass of crystalline and schistose rocks flanked on each side by a zone of Mesozoic beds and on the north by an outer band of Tertiary deposits. On the Italian side there is usually no zone of folded Eastern Alps. Tertiaries and the Mesozoic band forms the southern border of the chain. Each of these zones is folded within itself, and the folding is more intense on the Bavarian side than on the Italian, the folds often leaning over towards the north. The Tertiary zone of the northern border is of especial significance and is remarkable for its extent and uniformity. It is divided longitudinally into an outer zone of Molasse and an inner zone of Flysch. The line of separation is very clearly' defined; nowhere does the Molasse pass beyond it to the south and nowhere does the Flysch extend beyond it to the north. The Molasse, in the neighbourhood of the mountains, consists chiefly of conglomerates and sandstones, and the Flysch consists of sandstones and shales; but the Molasse is of Miocene and Oligocene age, while the Flysch is mainly Eocene. The relations of the two series are never normal. Along the line of contact, which is often a fault, the oldest beds of the Molasse crop out, and they are invariably overturned and plunge beneath the Flysch. A few miles farther north these same beds rise again to the surface at the summit of an anticlinal which runs parallel to the chain. Beyond this point all signs of folding gradually cease and the beds lie flat and undisturbed. The Flysch is air extraordinarily thick and uniform mass of sandstones and shales with scarcely any fossils excepting fucoids. It is intensely folded and is constantly separated from the Mesozoic zone by a fault. Throughout the whole extent of the Eastern Alps it is strictly limited to the belt between this fault and the marginal zone of Molasse. Eocene beds, indeed, penetrate farther within the chain, but these are limestones with nummulites or lignite-bearing shales and have nothing in common with the Flysch. But although the Flysch is so uniform in character, and although it forms so well-defined a zone, it is not everywhere of the same age. In the west it seems to be entirely Eocene, but towards the east intercalated beds with Inoceramus, &c., indicate that it is partly of Cretaceous age. It is, in fact, a facies and nothing more. The most probable explanation is that the Flysch consists of the detritus washed down from the hills upon the flanks of which it was formed. It bears, indeed, very much the same relation to the Alps that the Siwalik beds of India bear to the Himalayas. The Mesozoic belt of the Bavarian and Austrian Alps consists mainly of the Trias, Jurassic and Cretaceous beds playing a comparatively subordinate part. But between the Trias of the Eastern Alps and the.Trias of the region beyond the Alpine folds there is a striking contrast. North of the Danube, in Germany as in England, red sandstones, shales and conglomerates pre-dominate, together with beds of gypsum and salt. It was a continental formation, such as is now being formed within the desert belt of the globe. Only the Muschelkalk, which does not reach so far as England, and the uppermost beds, the Rhaetic, contain fossils in any abundance. The Trias of the Eastern Alps, on the other hand, consists chiefly of great masses of limestone with an abundant fauna, and is clearly of marine origin. The Jurassic and Cretaceous beds also differ, though in a less degree, from those of northern Europe. They consist largely of lime-stone; but marls and sandstones are by no means rare, and there are considerable gaps in the succession indicating that the region was not continuously beneath the sea. Tithonian fossils, characteristic of southern Europe, occur in the upper Jurassic, while the Gosau beds, belonging to the upper Cretaceous, contain many of the forms of the Hippuritic sea. Nevertheless, the difference between the deposits on the two sides of the chain shows that the central ridge was dry land during at least a part of the period. The central zone of crystalline rock consists chiefly of gneisses and schists, but folded within it is a band of Palaeozoic rocks which divides it longitudinally into two parts. Palaeozoic beds also occur along the northern and southern margins of the crystalline zone. The age of a great part of the Palaeozoic belts is somewhat uncertain, but Permian, Carboniferous, Devonian and Silurian fossils have been found in various parts of the chain, and it is not unlikely that even the Cambrian may be represented. The Mesozoic belt of the southern border of the chain extends from Lago Maggiore eastwards. Jurassic and Cretaceous bedsplay a larger part than on the northern border, but the Trias still predominates. On the west the belt is narrow, but towards the east it gradually widens, and north of Lago di Garda its northern boundary is suddenly deflected to the north and the zone spreads out so as to include the whole of the Dolomite mountains of Tirol. The sudden widening is due to the great Judicaria fault, which runs from Lago d'Idro to the neighbourhood of Meran, where it bends round to the east. The throw of this fault may be as much as 2000 metres, and the drop is on its south-east side, i.e. towards the Adriatic. It is probable, indeed, that the fault took a large share in the formation of the Adriatic depression. On the whole, the Mesozoic beds of the southern border of the Alps point to a deeper and less troubled sea than those of the north. Clastic sediments are less abundant and there are fewer breaks in the succession. The folding, moreover, is less intense; but in the Dolomites of Tirol there are great outbursts of igneous rock, and faulting has occurred on an extensive scale. Essay Walker sc. L.1 Triassic, Archaean & Metamorphic, Permian I+ ++I Plutonic Rocks Carboniferous. including 1.11 older Paiaeoaoicsooks is places Volcanic Rocks West of a line which runs from Lake Constance to Lago Maggiore the zones already described do not continue with the same simplicity. The zone of the Molasse is little swiss changed, but the Flysch is partly folded in the Mesozoic Alps. belt and no longer forms an absolutely independent band. The Trias has almost disappeared, and what remains is not of the marine type characteristic of the Eastern Alps but belongs rather to the continental facies which occurs in Germany and France. Jurassic and Cretaceous beds form the greater part of the Mesozoic band. On the southern side of the chain the Mesozoic zone disappears entirely a little west of Lago Maggiore and the crystalline rocks rise directly from the plain. Perhaps the strangest problem in the whole of Switzerland is that presented by the so-called Klippen. Within the Alps, when normally developed, we may trace the individual folds for long distances and observe how they arise, increase and die out, to be replaced by others of similar direction. But at times, within or on the border of the northern Eocene trough, the continuity of the folds is suddenly broken by mountain masses of quite different constitution. These are the Klippen, and they are especially important in the Chablais and between the Lakes of Geneva and Thun. Not only is the folding of the Klippen wholly independent of that of the zone in which they lie, but the rocks which form them are of foreign facies. They consist chiefly of Jurassic and Triassic beds, but it is the Trias and the Jura of the Eastern Alps and not of Switzerland. Moreover, although they interrupt the folding of the zone in which they occur, they do not disturb it: they do not, in fact, rise through the zone, but lie upon it like unconformable masses—in other. words, they rest upon a thrust. plane. Whence they have come into their present position is by no means clear; but the character of the beds which form them indicates a distant origin. It is interesting to note, in this Q Quaternary Tertiary Cretaceou.e Jurassic Subalpine N 752 N. Chem [GEOLOGY agelf/uh Cretaceous d, Eocene Range Eocene Jurassic Range T Kl. Wii.dgaRe Ros'aetoce f- Rig/ Rig! Hochffuh Ter Rbmenstalden r Ter ( Jr S j Jr Thai Schachenthal 7' r p ._~ •.-.` 1 +- /, ~ji n Z~i~i'\11~-1-" c _ Ga Sc a c a Sc aSc Jr Ter r Ce J ' A Cretaceous Metamorphic Rocks & J R a: Tertiary A Aar Massif Gotthard Massif .... J r .~ P.Torno r •~ % •(a Medq s-~ IMeientho '' l. Val Chironico ~Pl J 1wtF / ll : N~ i~ \\~~((((l%y - - Jr Basal Tessiner Mass B. Punta del roar B1 Seegebirge Southern Edge Vat Mohne N k.. _.'k.. :• `~j ~F'\~~~d~3E?~I3a .>-,~:..d/.>JTI//IMFM.S.Saluatore P Pons.'d'Arzo Cr Lugano Tr Pq qL Lugano Bo/erns y~~ ~\H~~~~~\\`.`\\`\\`\\\\~\~~i~C~~s'gan,~o~MOCr~ rcati rvha~x gf/ ~{/° Y°k;Y ,—0.~ : ~a~~– __ s _ _ eel/lnroca Camipnoro Plrso ferrate Pedrinata Plain of Lombardy Pp Sc Pp a Sc a s Sc a Sc G a M Sc Metamorphic RocksTr Jr Cr Ter Ter Ter. Tertiary Cr. Cretaceous Jr. Jurassic Tr. Triassic agar C. Schmidt C. Carboniferous & Verrucano Sc. Sericitic Soh/Ms a. Amphibolite a q M. Marble E Ga. Gneiss & Mica Schist ° cz A-G. Augen Gneiss Pq. Quartz Porphyry Pp. Porphyrite Gr. Granite P. Protogin aC e connexion, that the pebbles of the Swiss Molasse are not generally such as would be derived from the neighbouring mountains, but resemble the rocks of the Eastern Alps. The Klippen are, no doubt, the remains of a much larger mass brought into the region upon a thrust-plane, and much of the Molasse has been derived from its destruction. Although the explanation here given of the origin of the Swiss Klippen is that which now is usually accepted, it should be mentioned that other theories have been proposed to account for their peculiarities. In the Western Alps the outer border of Molasse persists; but it no longer forms so well-defined a zone, and strips are infolded western amongst the older rocks. The Eocene ha% altogether A 1ps, lost its independence as a band and occurs only in patches within the Mesozoic zone. The latter, on the other hand, assumes a greater importance and forms nearly the whole of the subalpine ranges. It consists almost entirely of Jurassic and Cretaceous beds, the Trias in these outer ranges being of very limited extent. The main chain is formed chiefly of crystalline and schistose rocks, which on the Italian side rise directly from the plain without any intervening zone of Mesozoic beds. But it is divided longitudinally by a well-marked belt of stratified deposits, known as the zone of the Brianconnais, composed chiefly of Carboniferous, Triassic and Jurassic beds. The origin of the schistose rocks has long been under discussion, and controversy has centred more particularly around the schistes lustres, which are held by some to be of Triassic age and by others to be pre-Carboniferous and even, perhaps, Archaean. Partly in consequence of the uncertainty as to the age of these and other rocks, there is considerable difference of opinion as to the structure of the Western Alps. According to the view most widely accepted in France the main chain as a whole forms a fan, the folds on the eastern side leaning towards Italy and those on the western side towards France. The zone of the Brianconnais lies in the middle of the fan. From the above account it will at once appear that between the convex and the concave margins of the Alpine chain there is a striking difference. Upon the outer side of the arc the central zone of crystalline rocks is flanked by Mesozoic and Tertiary belts; towards the west, indeed, the individuality of these beltsis lost, to a large extent, but the rocks remain. Upon the inner side the Tertiary band is found only in the eastern part of the chain, while towards the west, first the Tertiary and _ then the Mesozoic band disappears against the modern Aareym of deposits of the low land. The appearance is strongly the ps. suggestive of faulting; and probably the southern margin of the chain lies buried beneath the plain of northern Italy. The chain of the Alps was not raised by a -single movement nor in a single geological period. Its growth was gradual and has not been uniform throughout. In the Eastern Alps the central rseems to have been in existence at least Age 0t the ridge AJps. as early as Triassic times, but it has since been subject to several oscillations. The most conspicuous folding, that of the Mesozoic and Tertiary belts, must have occurred in Tertiary times, and it was not completed till the Miocene period. The structure of the zones in the Bavarian Alps seems to suggest that the chain grew outwards in successive stages, each stage being marked by the formation of a boundary fault. A precisely similar structure is seen in the Himalayas. 11. Flora.—The Alps owe the richness and beauty of their plant life partly to their position as the natural boundary between the "Baltic" flora on the north and the "Mediterranean" flora on the south, but chiefly to the presence on their heights of a third flora which has but little in common with either of the others. The stronghold of this last, the distinctively " Alpine " flora, is the region above the tree-limit. Its closest relationship is with the flora of the Pyrenees; but an alpine flora is characteristic of all the lofty mountains of central Europe. According to J. Ball, 2010 well-marked species of flowering plants occur within the limits of the Alps. If now we confine our attention to the alpine and higher regions of the Alps and exclude from our list all those plants which, however abundant in these regions, are not less so in the adjacent lowlands, we have left some 700 species (693, according to Dr Christ). We must observe,. as regards the plants of the lower alpine region, that it is the actual presence of a forest vegetation, rather than the theoretical tree-limit, which affects their vertical distribution; so that, e.g. they overflow into the extensive clearings made by man in the primeval mountain forests. Indeed, an analysis of the composition of the alpine flora as a whole leads to the conclusion that the chief bond of union between its members consists in the treeless character of their habitat. We may broadly distinguish two main geographical elements in the alpine flora, namely, the northern element and the endemic element. This division (which is not, however, strictly exhaustive) directs special attention to what is undoubtedly the most striking feature of the flora—namely, that of its 693 species no less than 271 reappear in the extreme north. This relation of the arctic to the alpine flora is all the more remarkable in view of the very important differences between the arctic and alpine climates. The following circumpolar species are common, and widely diffused throughout the whole of the Alps: Silene acaulis, Dryas octopetala, Saxifraga oppositifolia, S. aizoides, S. stellaris, Erigeron alpinus, Azalea procumbens, Myosolis alpestris, Polygonum viviparum, Salix retusa, S. her bacea, Phleum alpinum, Juniperus nana. The proportion of northern forms, as regards both species and individuals, increases as we ascend to the higher regions. In the highest vegetation-zone, the snow-region—i.e. on islands of rock above the snow-line—they attain to an equality with the endemic forms. As examples of northern flowers which are characteristic of the snow-region, we may mention Silene acaulis, Eritrichium nanum and Arenaria ciliata. On the other hand, typical endemic species of this highest zone are Androsace helvetica, A. glacialis, Petrocallis pyrenaica and Cherleria sedoides. All the plants just named, we may observe, are " cushion-plants." Their compact, moss-like growth and general structural peculiarities are not an expression of mutual affinity, but are in adaptation to the combined cold and dryness of their habitat. It is noteworthy that among the northern plants of the alpine zone, in the narrower sense of the term (i.e. of the region between the tree-limit and the snow-line), there is a marked predominance of species that affect moist localities; and conversely, the majority of alpine flowers of wet habitat are found also in the north. For example, in the genus Primula, a highly characteristic genus of the alpine flora, whose members are among the most striking ornaments of the rocks, the single northern species, P. farinosa, grows only in marshy meadows. On the whole, then, adaptation to cold and wet is the note of the northern element. As for the explanation of the community between the alpine and arctic floras, all authorities are agreed that the key to the problem is furnished by the occurrence of the glacial period. In the ice-free belt, between the northern ice-sheet and,the vastly extended glaciers of the Alps, the two floras must have found a common refuge and congenial conditions of existence; and this view is confirmed by direct palaeontological evidence. With the return of a milder climate, the so-called northern forms of the present alpine flora were split in two, one portion following close on the northern ice in its gradual retreat to the Arctic, the other following the shrinking glaciers till the plants were able to establish (or re-establish) themselves on the slopes of the Alps. The same explanation covers the case of the similarity of the flora (not merely as regards the northern element) on all thehigh mountains of central Europe. So much seems to be beyond reasonable doubt. But at this point disagreement begins between the most eminent writers on the subject. While some (e.g. Sir J. D. Hooker, Heer) regard the Arctic, and some (e.g. Wettstein) the Alps, as the original home of at least the bulk of the "northern" element, others (e.g. Ball, Christ) locate this in the highlands of temperate Asia. For it is a remarkable fact that, of the 230 northern species which are most typical of the far north, 182 are found also in the Altai (taking this as a collective name for the mountains that form the southern boundary of Siberia). In any case, however, the migration of these plants to the Alps must for the most part have taken place via the Arctic. The possibility of any extensive east to west migration having taken place direcpty from the Altai to the Alps seems excluded by the fact that 50% of the arctico-altaic alpine plants are absent from the Caucasus. A score of species, it is true—not such a number, be it observed, as was formerly supposed—are common to the Alps and Altai, but absent from the Arctic. But the species composing this Altaic element are not so numerous as the arctico-alpine species that are absent from the Altai. On the whole, a common origin in the north for at least the arcticoaltaic group of alpine plants seems to be the most reasonable hypothesis. Side by side with the northern element (which in some respects, we may observe to point the contrast, would be better named the tundra-element) we find a group of species usually spoken of as the xerothermic or meridional element. These do not, how-ever, form an " element," in the strict geographical sense in which this term is otherwise used here. They are those species which, on general phyto-geographical grounds, must be regarded as having originated under steppe-like conditions. Their affinities are chiefly, though not exclusively, with the present Mediterranean flora—about fifty are of presumably Mediterranean origin —and a large proportion of them are restricted to the southern slopes of the Alps. The following, however, among others, are distributed throughout the whole, or a great part, of the range: Colchicum alpinum, Crocus vernus, Orchis globosa, Petrocallis pyrenaica, Astragalus depressus, A. aristatus, Oxytropis Halleri, Eryngium alpinum, Erica carnea, Linaria alpina, Globularia nudicaulis, G. cordifolia, Leonto podium alpinum. The last named (the well-known " edelweiss ") is at the present day characteristic of the Siberian steppes. The presence of these plants among the alpine flora is traceable to the steppe-like conditions which prevailed in central Europe both during the warmer inter-glacial periods and (probably) for a time after the close of the ice-age. Subsequently, as the climate of the plains assumed a colder and more humid character, they retired before the invading forests to the high mountains. Here, in the intenser insolation which they enjoy on the alpine slopes, they seem to find a compensation for the drawbacks incidental to the altitude of their present station. As regards now the endemic element as a whole, the question as to the time and place of its origin is of a highly complicated and controversial nature. The question, too, in the case of this element, is necessarily of genetic rather than purely geographical scope. It must suffice to say that the weight of scientific opinion inclines to the view that at least the majority of endemic species are of pre-glacial origin, and are either strictly indigenous or products of the neighbouring lowlands. About 40 % of the endemic element in the alpine flora are endemic also in the narrower sense, i.e. they are confined to the Alps. Many of them, are restricted to some one small portion of the chain; these occur chiefly in the southern and eastern Alps. It is an interesting fact that the centrally situated Bernese Alps produce hardly a single peculiar species. The greater richness of certain districts in the matter of species is partly due to the variety of soils encountered therein; but in part may be explained by the fact that these districts were the first to be freed from the ice-sheet at. the end of the glacial period. The following is a list of the most thoroughly characteristic alpine plants—all of them ipso facto members of the endemic element—which are at once peculiar to the Alps (or practically so) and widely distributed within the limits of the chain. These are: Fesluca pulchella, Carex microstyla, Salix caesia, Rumex nivalis, Alsine aretioides, Aquilegia alpina, Thlaspi rotundifolium, Saxifraga Seguieri, S. aphylla, Astragalus leontinus, Daphne striata, Eryngium alpinism, Bupleurum stellatum, Androsace helvetica, A. glacialis, Gentiana bavarica, Phyteuma humile, Campanula thyrsoidea, C. cenisia, Achillea atrata, Cirsium spinosissimurn, Crepis Terglouensis. AuTxoRITIEs.—Among the voluminous literature on alpine flora, the following works are particularly noteworthy:—Ball, " On the Origin of the Flora of the European Alps," in Proceed. of the Roy. Geog. Soc., 1879; Bennett, The Flora of the Alps, 2 vols. with 12o coloured plates (1896); Briquet, " Les Colonies vegetales xerothermiques des alpes lemaniennes,' in Bull. d. 1. Murithienne, soc. valaisienne des sciences nat., xxvii. and xxviii. (1898–1899); Alph. de Candolle, " Sur les causes de 1'inegale distribution des plantes rares clans la chaine des Alpes," Extr. des Actes du Congres botan. internat. de Florence (1875) ; Chodat u. Pampanini, "Sur la distribution des plantes des alpes austro-orientales," Extr. du Globe, organe de la soc. de geographie de Geneve, tome xli. (1902) ; H. Christ, Das Pflanzenleben der Schweiz (1882)—the chief classic on the subject; Engler, Die Pflanzenformationen and die pflanzengeographische Gliederung der Alpenkette (19o1); Heer, Ueber die nivale Flora der Schweiz (1885); Jerosch, Geschichte and Herkunft der schweizerischen Alpenflora; eine Ubersichl fiber den gegenwartigen Stand der Frage (1903); Schroter, Das Pftanzenleben der Alpen (Zurich, 1908) ; R. von Wettstein, Die Geschichte unserer Alpenflora (1896). The best book of coloured plates is the Atlas der Alpenflora, in 5 vols., pub. by the Deutscher u. Oesterreichischer Alpenverein (2nd. ed., 1897). 12. Fauna.— The fauna of the lower zones in the Alps is, on the northern side of the chain, practically identical with that of central Europe, and on the southern side with that of the Mediterranean basin. But in the higher regions it presents many features of special interest alike to the zoologist and the traveller. It seems therefore best to treat here principally of the animal inhabitants of the high Alps. Though among mammalia— as also in the case of the birds—there are but few forms peculiar to the Alps, many interesting animals have found in the high mountains at least a temporary refuge from man. The European bison, the urns, the elk and the wild swine have disappeared since Roman times. But the lynx (Lynx vulgaris) perhaps lingers in remote parts, and the brown bear (Ursus arctos) still survives in the dense forests of the Lower Engadine. The fox (Canis vulpes), the stonemarten (Mantes foina) and the stoat or ermine (Putorius erminea) range in summer above the tree-limit. The Ungulata are represented by the chamois (Rupicapra tragus) and the bouquetin or steinbock (Capra ibex). The former—the sole representative, in western Europe, of the antelopes—is found elsewhere only in the Pyrenees, Carpathians, Caucasus and the mountains of eastern Turkey; the latter survives only in the eastern Graian Alps. Of the Rodentia the most interesting and conspicuous is the marmot (Arctomys marmota), which lives in colonies close to the snow-line. The snow-mouse (Arvicola nivalis) is confined to the alpine and snow regions, and is abundant at these levels throughout the whole chain of the Alps. The mountain hare (Lepus variabilis or timidus) replaces the common hare (Lepus europaeus) in the higher regions; though absent from the intervening plains it again appears in the north of Europe and in Scotland. Among the Insectivora, the alpine shrew (Sorex alpinus) is restricted to the Alps. Of the Cheiroptera (bats) only Vesperugo maurus is characteristically alpine. The birds of the Alps are proportionately very numerous. The lammergeyer (Gypaetus barbatus) , once common, is now extremely rare, even if it has not already become extinct in the Alps; but the golden eagle (Aquila chrysaetos) still holds its own. Some of the smaller birds of prey are not uncommon, but there is none that can be regarded as specially characteristic either of the Alps as a whole or of the alpine region. As characteristic birds of the snow-region may be mentioned the alpine though (Pyrrhocorax alpinus), which is frequently seen at the summits even of the loftiest mountains, the alpine swift (Cypselus melba), the wall-creeper (Tichodroma muraria), snow-finch (Montifringilla nivalis) and ptarmigan (Lagapus mutus); the geographical distribution of this last being similar to that of the mountain hare. The black redstart (Ruticilla titys), though common in the lower regions, isalso met with in fair numbers almost up to the snow-line. The raven (Corvus corax) is fairly common in the alpine and sub-alpine regions. On the highest pastures we find, further, the alpine accentor (Accentor collaris) and the alpine pipit (Anthus spipoletta). The crag-martin (Cotyle rupestris) haunts lofty cliffs in the alpine region. On the upper verge of the pine forestsy or in the scrubby vegetation just beyond, the following are not uncommon —black woodpecker (Picus rnartius), ring-ousel (Turdus torquatus), Bonelli's warbler (Phylloscopus Bonellii), crested tit (Parus cristatiss), citril finch (Citrinella alpina), siskin (Chrysomitris spinus), crossbill (Loxia curvirostra), nutcracker (Nucifraga caryocatactes), blackcock (Tetrao tetrix), and the alpine varieties of the marsh-tit (Parus palustris, borealis) and tree-creeper (Certhia familiaris, costae). The remaining classes of Vertebrata are very sparsely represented in the high Alps; and what few species occur are mostly common to the plains as well. In fact, among the remaining land vertebrates, only the black salamander (Salamandra atra) is exclusively alpine. This interesting animal, though a member of the Amphibia, is terrestrial and viviparous. The former connexion between the Arctic and the Alps, which has left such unmistakable traces in the present alpine flora, affords, as regards the fauna also, the only possible explanation of the present geographical distribution of many alpine forms; but it is chiefly among the Invertebrata that we find this collateral testimony to the influence of the glacial period. In this respect we may note that two small crustaceans, Diaptomus bacillifer and D. denticornis, swarm in the ice-cold waters of the highest alpine tarns throughout the entire chain; and the former of these is also a characteristic inhabitant of pools formed from melting snow in the extreme north. Among the remaining divisions of Invertebrata special mention may be made of the air-breathing Arthropoda—on the whole the most important and interesting group. About one-third of the animals belonging thereto that occur in the higher regions are exclusively alpine (or alpine and northern) ; these characteristically alpine forms being furnished chiefly by the spiders, beetles and butterflies. Most numerous are the beetles. Those of the highest zoneare remarkable for the great predominance of predaceous species and of wingless forms. In this last respect they present a striking analogy with the endemic coleopterous fauna of oceanic islands. As for the butterflies, not more than one-third of the species found in the alpine region occur in the neighbouring lowlands. The relations between alpine butterflies and plants are especially interesting, as regards not only their bionomic interdependence but also the analogies of their geographical distribution. It should be noted that butterflies are the chief agents in securing the continued existence of such alpine flowers as depend on insect fertilization, the other insect fertilizers being mostly wanting at great heights. The classic of alpine zoology is F. von Tschudi's Das Tierleben der Alpenwelt (11th ed., 1890). See also zoological section, by K. W. v. Dalla Torre, of Anleitung zn wissenschaftlichen Beobachtungen auf Alpenreisen. For the Vertebrata, see V. Fatio's Faune des vertebres de la Suisse (5 vols., 1869–1904). Die Tierwelt der Hochgebirgsseen, by F. Zschokke (19oo) is an important treatise on an interesting department of alpine natural history. C. Zeller's Alpentiere im Wechsel der Zeit (1892) gives a reliable account of the gradual disappearance of some of the larger forms of life from the Alps: For the inter-relations of alpine insects and flowers, see H. Muller's Alpenblumen, ihre Befruchtung durch Insekten, and ihre Anpassung an dieselben (1881). (H. V. K.)
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