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GLACIER . As to Alpine legends, consult Maria See also:Savi-See also:Lopez, Leggende delle Alpi (1889); M. Tscheinen, Walliser-Sagen (1872); Th. Vernaleken, Alpensagen (1858); and I. V. See also:Zingerle, Sagen aus See also:Tirol (1859); and as to Alpine See also:poetry—J. See also:Adam, Der Natursinn in der deutschen Dichtung (1906); E. A. See also:Baker and F. E. See also:Ross, The See also:Voice of the Mountains (1905, an See also:anthology in See also:verse and See also:prose); A. von See also:Haller, See also: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. See also:Alton, Die ladinischen Idiome in Ladinien, Groden, Fassa, Buchenstein, Ampezzo (1879); J. A. Chabrand and A. de Roches d'Aiglun, See also:Patois See also:des Alpes cottiennes (1877); Z. and E. Pallioppi, Dizionari dels Idioms Romauntschs d'Engiadina ota e See also:bassa, &c. (1895); A. Socin, Schriftsprache and Dialekle See also:im Deutschen (1888); F. J. Stalder, Die Landessprachen der Schweiz (1819), and J. Zimmerli, Die See also:deutsch franzosische Sprachgrenze in der Schweiz (3 vols., 1891–1899) ; besides the See also:great Swiss See also:Dialect See also:Dictionary (Schweiz. Idiotikon) in course of publication since 1881. As to the See also:history of the See also:Alps, the following See also:works See also: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. See also:Grand-See also:Carteret, La Montagne a travers See also:les ages (2 vols., 1902–1904) ; G. Oberziner, Le Guerre di See also:Augusta contra i populi See also:alpini (1900); E. Oehlmann, Die Alpenpdsse im Mittelalter(1878–1879); R. Reinhard, Passe and Strassen in den Schweizer Alpen (1903); and L. Vaccarone, Le See also:Vie delle Alpi Occidentali negli antichi tempi (1884) ; while W. A. B. Coolidge's Josias See also: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 See also:list includes all the See also: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 See also:France, du Piemont, et de la See also:Savoie (180,) ; M. T. See also: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, See also: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. See also:Deluc and P. G. Dentan, Relation de differenis voyages' dans les Alpes du Faucigny (1776); E. See also:Desor, Excursions et sejours dans les glaciers (2 See also:series, 1844–1845) ; C. M. See also:Engelhardt, Naturschilderungen aus den hochsten Schweizer-Alpen (184o), and Das See also:Monte-See also:Rosa and See also:Matterhorn-Gebirg (1852); J. D. See also:Forbes, Travels through the Alps of See also:Savoy (1843, new ed., 1900); See also:Sir See also: See also:Hoffmann, Wanderungen in der Gletscherwelt (1843); F. J..Hugi, Naturhistorische Alpenreise (183o); C. J. See also:Latrobe, The Alpenstock (1829) and The Pedestrian (1832); J. R. and H. See also:Meyer, Reise auf den See also: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 See also:Bergen, nemlich des Niesens and Stockhorns (1606);' C. Rohrdorf, Reise fiber die See also:Grindelwald-Viescher-Gletscher and Ersteigung des Gletschers des Jungfrau-Berges (1828); H. B. de See also:Saussure, Voyages dons les Alpes (4 vols., 1779–1796) ; A. Schaubach, Deutsche Alpen (4 vols., 1845-1847) ; J. J. See also: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) ; See also:Albert See also: F. See also: Freshfield, Across See also:Country from Thonon to See also:Trent (1865), and See also:Italian Alps (1875); Mrs See also: See also:Hudson and E. S. See also:Kennedy, Where there's a Will there's a Way (1856) ; E. Javelle, Souvenirs d' un Alpinisie (1886, Eng. trans., 1899); S. W. See also: F. Mummery, My Climbs in the Alps (1895); See also:Norman-Neruda, The Climbs of (1899) ;.. Peaks, Passes and Glaciers (3 vols., 1859–1862) ; L. Purtscheller, Uber Fels and Firn (1901); E. See also:Rambert. Ascensions it fldneries (2 vols., 1888) ; G. Rey, Il Monte Cervino (1904) ; John See also:Ruskin, vol. iv. (On See also:Mountain Beauty) of See also:Modern Painters (1856); A. von Ruthner, Aus den Tauern (1864) and Aus Tirol (1869); V. See also:Sella and D. Vallino, Monte Rosa e Gressoney (189o) ; F. See also: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. See also:Stephen, The Playground of See also:Europe (1871) ; B. Studer, Geschichte der physischen Geographie der Schweiz bis 1815 (1863); G. Studer and others, See also:Berg- and Gletscherfahrten (2 series, 1859 and 1863); G. See also: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. See also:Tyndall, The Glaciers of the Alps (186o), See also:Mountaineering in 1861 (1862), and See also:Hours of Exercise in the Alps (1871); J. J. Weilenmann, Aus der Firnenwelt (3 vols., 1872–187i); E. See also:Whymper, Scrambles amongst the Alps (1871); Sir A. See also:Wills, Wanderings among the High Alps (1856), and The " See also:Eagle's See also:Nest " in the Valley of Sixt (186o) ; G. Yeld, Scrambles in the Eastern Graians (1900) ; H. See also:Zschokke, Reise auf die Eisgebirge des Kantons See also:Bern and Ersteigung ihrer hochsten Gipfel im See also:Sommer von 1812 (1813); E. Zsigmondy, lm Hockgebirge (1889); M. Zurbriggen, From the Alps to the See also:Andes (1899).
Many useful See also:practical hints as to climbing are to be found in C. T. Dent and others, Mountaineering (1892, 3rd ed., 1900, " See also:Badminton Library ") ; the See also:Manuel d'Alpinisme (1904, publ. by the See also:French Alpine Club) ; J. Meurer, Handbuch der alpinen See also:Sport (1882), Katechismus See also:fur Bergsteiger (1892), and Der Bergsteiger im Hochgebirge (1893); and C. See also: Zsigmondy, Die Gefahren der Alpen (1885, Fr. trans., 1889). There are also See also:special See also: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. See also:Duhamel and F. Perrin, Guide du Haut See also:Dauphine (1887, with supplement in 189o, Eng. trans., 1892 and 1905); L. Purtscheller and H. See also: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 See also:Uri, and V. See also:Wolf von Glanvell, Dolomitenfuhrer (1898). As regards the See also: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 See also:period see, besides the more See also:general works of travel mentioned above, the publications (that date from 1863) of the various Alpine Clubs—the Alpine See also:Journal (See also:English A. C.), theAnnuaire, Bulletin, La Montague, and Revue alpine (French A. C.), the Jahrbuch, Mitteilungen, Verhandlungen, and Zeitschrift (German and See also:Austrian A. C.), the Alpinista, Bollettino, and Rivista Mensile (Italian A. C.), and the Alpina, See also:Echo des Alpes, Jahrbuch, Schweizer Alpen-Zeitung (Swiss A. C.), besides those of the smaller See also: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 See also:Prime Ascensioni nelle Alpi Occidentali (3rd. ed., 189o—this See also: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. See also: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. See also:Mathews, The See also:Annals of Mont Blanc (1898). Lives of some of the most celebrated mountain guides have been written in C. D. See also:Cunningham and W. de W. Abney, Pioneers of the Alps (2nd ed., 1888). (2) Maps.—There is no See also:good modern and fairly large-See also:scale See also:map of the entire See also: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, See also:save that portion See also:south of the range of Mont Blanc. All the countries which include Alpine districts have now issued See also:official See also:Government maps. The French map on a scale of I :80,000 is clearer and more accurate than that on a scale of 1: See also: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 See also:Bureau, under the See also:title of Siegfried See also:Atlas (scale 1 :5o,00o for the Alpine districts), which has quite superseded the See also: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. See also: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. See also:Kurz. The German and Austrian Alpine Club is See also:publishing a very See also: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. See also:Geology.—The Alps See also:form but a small portion of a great See also:zone of crumpling which stretches, in a series of curves, from the Atlas Mountains to the Himalayas. Within this zone thecrust of the See also:earth has been ridged up into a complex See also:system of creases or folds, out of which the great mountain chains of See also:southern Europe and See also: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 See also:part at least, to the subsidence of portions of the folded See also:belt and their subsequent See also:burial by more See also:recent accumulations. Such a See also:gap is that between the Alps and the Carpathians, but a glance at a See also:geological map of the region will show that the folding was probably at one See also: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 See also:echelon. The folds run, in general, in the direction of the chain, and together they form an arc around the See also:plain of See also:Lombardy and See also:Piedmont. Outside this arc lies a depression along which the See also:waters of the upper See also:Danube and the See also:lower See also:Rhone find their way towards the See also:sea; and beyond the the See also:ancient crystalline masses of Bohemia, the See also:Black See also:Forest and the central See also:plateau of France, together with the intervening Mesozoic beds of southern See also:Germany and the See also:Jura. The depression is filled by See also:Miocene and later beds, which for the most part See also:lie See also: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 See also:age and in direction from that of the Alps. To assist in forming a clear See also:idea of the relations of the Alps to the surrounding regions, a See also:simple See also:illustration will suffice. Upon a table covered by a See also:cloth See also:lay two books in the relative positions shown in figure. The See also: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 See also:angle between the two books, and the cloth pushed towards the corner, it will at once be rucked up into a See also:fold which will follow a See also:curve not unlike that of the Alps. The precise See also: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 See also:adjustment on the table. not only a See also: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 See also: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 See also: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 See also:borne in mind that the resisting See also:mass is not necessarily at the See also:surface. Such is in outline the See also: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 See also: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 See also:side by a zone of Mesozoic beds and on the See also:north by an See also:outer See also:band of See also:Tertiary deposits. On the Italian side there is usually no zone of folded Eastern Alps. See also: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 See also: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 See also: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 See also:Eocene. The relations of the two series are never normal. Along the line of contact, which is often a See also:fault, the See also:oldest beds of the Molasse See also:crop out, and they are invariably overturned and plunge beneath the Flysch. A few See also:miles farther north these same beds rise again to the surface at the See also: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 See also: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 See also:lignite-bearing shales and have nothing in See also: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 See also:west it seems to be entirely Eocene, but towards the See also: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 See also:India See also:bear to the Himalayas. The Mesozoic belt of the Bavarian and Austrian Alps consists mainly of the Trias, See also: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 See also:gypsum and See also:salt. It was a See also:continental formation, such as is now being formed within the See also:desert belt of the globe. Only the See also:Muschelkalk, which does not reach so far as England, and the uppermost beds, the See also:Rhaetic, contain fossils in any abundance. The Trias of the Eastern Alps, on the other See also:hand, consists chiefly of great masses of See also:limestone with an abundant See also: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 See also:lime-See also: 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 See also: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 See also: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 See also: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.
See also:Essay See also: 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 See also:Switzerland is that presented by the so-called Klippen. Within the Alps, when normally See also:developed, we may trace the individual folds for See also: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 See also:Geneva and See also: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 See also: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 See also:rest upon a thrust. See also:plane. Whence they have come into their See also:present position is by no means clear; but the character of the beds which form them indicates a distant origin. It is interesting to See also:note, in this Q See also:Quaternary Tertiary Cretaceou.e Jurassic Subalpine N 752 N. Chem [GEOLOGY agelf/uh Cretaceous d, Eocene Range Eocene Jurassic Range T Kl. Wii.dgaRe See also: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 See also: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 See also: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 _ _ See also: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. See also:Schmidt C. Carboniferous & Verrucano Sc. Sericitic Soh/Ms a. See also:Amphibolite a q M. See also:Marble E Ga. See also:Gneiss & See also:Mica Schist ° cz A-G. Augen Gneiss Pq. See also:Quartz See also:Porphyry Pp. Porphyrite Gr. See also: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 See also: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 See also: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 See also: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 See also: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 See also:fan, the folds on the eastern side leaning towards See also:Italy and those on the western side towards France. The zone of the Brianconnais lies in the See also:middle of the fan. From the above account it will at once appear that between the See also:convex and the See also: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 See also:low land. The See also: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 See also:movement nor in a single geological period. Its growth was See also: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 See also:grew outwards in successive stages, each See also:stage being marked by the formation of a boundary fault. A precisely similar structure is seen in the Himalayas. 11. See also:Flora.—The Alps owe the richness and beauty of their plant See also: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 See also:tree-limit. Its closest relationship is with the flora of the See also:Pyrenees; but an alpine flora is characteristic of all the lofty mountains of central Europe. According to J. See also:Ball, 2010 well-marked See also:species of flowering See also:plants occur within the limits of the Alps. If now we confine our See also: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 See also:left some 700 species (693, according to Dr See also: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 See also:vertical See also:distribution; so that, e.g. they overflow into the extensive clearings made by See also:man in the primeval mountain forests. Indeed, an See also:analysis of the See also:composition of the alpine flora as a whole leads to the conclusion that the See also:chief See also:bond of See also:union between its members consists in the treeless character of their See also:habitat. We may broadly distinguish two main See also:geographical elements in the alpine flora, namely, the northern See also:element and the endemic element. This See also: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 See also:arctic to the alpine flora is all the more remarkable in view of the very important See also: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, See also: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 See also:flowers which are characteristic of the snow-region, we may mention Silene acaulis, Eritrichium nanum and Arenaria See also: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 " See also:cushion-plants." Their compact, See also:moss-like growth and general structural peculiarities are not an expression of mutual See also:affinity, but are in See also:adaptation to the combined See also:cold and dryness of their habitat. It is noteworthy that among the northern plants of the alpine zone, in the narrower sense of the See also: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 See also: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 See also: But at this point disagreement begins between the most eminent writers on the subject. While some (e.g. Sir J. D. See also: On the whole, a common origin in the north for at least the arcticoaltaic See also:group of alpine plants seems to be the most reasonable See also:hypothesis. Side by side with the northern element (which in some respects, we may observe to point the contrast, would be better named the See also: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 See also:steppe-like conditions. Their See also: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: See also:Colchicum alpinum, See also:Crocus vernus, Orchis globosa, Petrocallis pyrenaica, Astragalus depressus, A. aristatus, Oxytropis Halleri, Eryngium alpinum, Erica See also:carnea, Linaria alpina, Globularia nudicaulis, G. cordifolia, Leonto See also:podium alpinum. The last named (the well-known " See also:edelweiss ") is at the present See also:day characteristic of the Siberian See also: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 See also:compensation for the drawbacks incidental to the See also: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 See also:scope. It must suffice to say that the See also: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 See also:peculiar species. The greater richness of certain districts in the See also: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, See also:Daphne striata, Eryngium alpinism, Bupleurum stellatum, Androsace helvetica, A. glacialis, Gentiana bavarica, Phyteuma humile, See also: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 See also:European Alps," in Proceed. of the See also:Roy. Geog. See also:Soc., 1879; See also:Bennett, The Flora of the Alps, 2 vols. with 12o coloured plates (1896); Briquet, " Les Colonies vegetales xerothermiques des alpes lemaniennes,' in See also:Bull. d. 1. Murithienne, soc. valaisienne des sciences nat., See also:xxvii. and See also:xxviii. (1898–1899); Alph. de See also:Candolle, " Sur les causes de 1'inegale distribution des plantes rares clans la chaine des Alpes," Extr. des Actes du Congres botan. internat. de See also: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); See also:Schroter, Das Pftanzenleben der Alpen (See also: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 See also:basin. But in the higher regions it presents many features of special See also:interest alike to the zoologist and the traveller. It seems therefore best to treat here principally of the See also:animal inhabitants of the high Alps. Though among See also: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 See also:elk and the See also:wild See also:swine have disappeared since See also:Roman times. But the See also:lynx (Lynx vulgaris) perhaps lingers in remote parts, and the See also: 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 See also:swift (Cypselus See also:melba), the See also:wall-creeper (Tichodroma muraria), snow-See also:finch (Montifringilla nivalis) and See also:ptarmigan (Lagapus mutus); the geographical distribution of this last being similar to that of the mountain hare. The black See also:redstart (Ruticilla titys), though common in the lower regions, isalso met with in See also:fair See also:numbers almost up to the snow-line. The See also:raven (See also: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 See also:pipit (Anthus spipoletta). The See also:crag-martin (Cotyle rupestris) haunts lofty cliffs in the alpine region. On the upper See also:verge of the See also:pine forestsy or in the scrubby vegetation just beyond, the following are not uncommon —black See also:woodpecker (See also:Picus rnartius), See also:ring-See also:ousel (Turdus torquatus), Bonelli's See also:warbler (Phylloscopus Bonellii), crested tit (Parus cristatiss), citril finch (Citrinella alpina), See also:siskin (Chrysomitris spinus), See also:crossbill (Loxia curvirostra), See also:nutcracker (Nucifraga caryocatactes), See also:blackcock (Tetrao tetrix), and the alpine varieties of the See also:marsh-tit (Parus palustris, borealis) and tree-creeper (Certhia familiaris, costae). The remaining classes of See also: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 See also:salamander (Salamandra atra) is exclusively alpine. This interesting animal, though a member of the See also: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 See also:collateral testimony to the See also: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 See also: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 See also: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 See also: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 See also:insect fertilization, the other insect fertilizers being mostly wanting at great heights. The classic of alpine See also:zoology is F. von Tschudi's Das Tierleben der Alpenwelt (11th ed., 1890). See also zoological See also: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 See also:treatise on an interesting See also:department of alpine natural history. C. See also: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 See also:insects and flowers, see H. 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