watershed before it attains the Mont Dolent (12,543 ft.). Thence after a short dip to the south-east, our chain takes near the Great St Bernard Pass the generally eastern direction that it maintains till it reaches Monte Rosa, whence it bends northwards, making one small dip to the east as far as the Simplon Pass. It is in the portion of the watershed between the Great St Bernard and the Simplon that the main chain maintains a greater average height than in any other part. But, though it rises in a number of lofty peaks, such as the Mont Vélan (12,353 ft.), the Matterhorn (14,782 ft.), the Lyskamm (14,889 ft.), the Nord End of Monte Rosa (15,132 ft.), and the Weissmies (13,226 ft.), yet many of the highest points of the region, such as the Grand Combin (14,164 ft.), the Dent Blanche (14,318 ft.), the Weisshorn (14,804 ft.), the true summit or Dufourspitze (15,217 ft.) of Monte Rosa itself, and the Dom (14,942 ft.), all rise on its northern slope and not on the main watershed. On the other hand the chain between the Great St Bernard and the Simplon sinks at barely half a dozen points below a level of 10,000 ft. The Simplon Pass corresponds to what may be called a dislocation of the main chain. Thence to the St Gotthard the divide runs north-east, all the higher summits (including the Monte Leone, 11,684 ft., and the Pizzo Rotondo, 10,489 ft.) rising on it, a curious contrast to the long stretch just described. From the St Gotthard to the Maloja the watershed between the basins of the Rhine and Po runs in an easterly direction as a whole, though making two great dips towards the south, first to near the Vogelberg (10,565 ft.) and again to near the Pizzo Gallegione (10,201 ft.), so that it presents a broken and irregular appearance. But all the loftiest peaks rise on it: Scopi (10,499 ft.), Piz Medel (10,509 ft.), the Rheinwaldhorn (11,149 ft.), the Tambohorn (10,749 ft.) and Piz Timun (10,502 ft.).
From the Maloja Pass the main watershed dips to the south-east for a short distance, and then runs eastwards and nearly over the highest summit of the Bernina group, the Piz Bernina (13,304 ft.), to the Bernina Pass. Thence to the Reschen Scheideck Pass the main chain is ill-defined, though on it rises the Corno di Campo (10,844 ft.), beyond which it runs slightly north-east past the sources of the Adda and the Fraële Pass, sinks to form the depression of the Ofen Pass, soon bends north and rises once more in the Piz Sesvenna (10,568 ft.).
The break in the continuity of the Alpine chain marked by the deep valley, the Vintschgau, of the upper Adige (Etsch) is one of the most remarkable features in the orography of the Alps. The little Reschen lake which forms the chief source of the Adige is only 13 ft. below the Reschen Scheideck Pass (4902 ft.), and by it is but 5 m. from the Inn valley. Eastward of this pass, the main chain runs north-east to the Brenner Pass along the snowy crest of the Oetzthal and Stubai Alps, the loftiest point on it being the Weisskugel (12,291 ft., Oetzthal), for the highest summits both of the Oetzthal and of the Stubai districts, the Wildspitze (12,382 ft.) and the Zuckerhütl (11,520 ft.) stand a little to the north.
The Brenner (4495 ft.) is almost the lowest of all the great carriage-road passes across the main chain, and has always been the chief means of communication between Germany and Italy. For some way beyond it the watershed runs eastwards over the highest crest of the Zillerthal Alps, which attains 11,559 ft. in the Hochfeiler. But, a little farther, at the Dreiherrenspitze (11,500 ft.) we have to choose between following the watershed southwards, or keeping due east along the highest crest of the Greater Tauern Alps. (a) The latter course is adopted by many geographers and has much in its favour. The eastward direction is maintained and the watershed (though not the chief Alpine watershed) continues through the Greater Tauern Alps, culminating in the Gross Venediger (12,008 ft.), for the Gross Glockner (12,461 ft.) rises to the south. Our chain bends north-east near the Radstädter Tauern Pass, and preserves that direction through the Lesser Tauern Alps to the Semmering Pass. (b) On the other hand, if from the Dreiherrenspitze we cleave to the true main watershed of the Alpine chain, we find that it dips south, passes over the Hochgall (11,287 ft.), the culminating point of the Rieserferner group, and then sinks to the Toblach Pass, but at a point a little east of the great Dolomite peak of the Drei Zinnen it bends east again, and rises in the Monte Coglians (9128 ft., the monarch of the Carnic Alps). Soon after our watershed makes a last bend to the south-east and culminates in the Terglou (9400 ft.), the highest point of the Julic Alps, though the Grintovc (8429 ft., the culminating point of the Karawankas Alps) stands more to the east. Finally our watershed turns south and ends near the great limestone plateau of the Birnbaumerwald, between Laibach and Görz.
As might be expected, the main chain boasts of more glaciers and eternal snow than the independent or external ranges. Yet it is a curious fact that the three longest glaciers in the Alps (the Great Aletsch, 1612 m., and the Unteraar and the Fiescher, each 10 m.) are all in the Bernese Oberland. In the main chain the two longest are both 914 m., the Mer de Glace at Chamonix and the Gorner at Zermatt. In the Eastern Alps the longest glacier is the Pasterze (rather over 614 m.), which is not near the true main watershed, though it clings to the slope of the Greater Tauern range, east of the Dreiherrenspitze. But the next two longest glaciers in the Eastern Alps (the Hintereis, 614 m., and the Gepatsch, 6 m.) are both in the Oetzthal Alps, and so close to the true main watershed.
The so-called alpine lakes are the sheets of water found at the foot of the Alps, on either slope, just where the rivers that form them issue into the plains. There are, however, alpine lakes higher up (e.g. the lake of Thun, and those in the Upper Engadine, in the heart of the mountains, though these are naturally smaller in extent, while the true lakes of the High Alps are represented by the glacier lakes of the Marjelensee (near the Great Aletsch glacier) and those on the northern slope of the Col de Fenetre, between Aosta and the Val de Bagnes. The most singular, and probably the loftiest, lake in the Alps is the ever-frozen tarn that forms the summit of the Roccia Viva (11,976 ft.) in the Eastern Graians.
Among the great alpine rivers we may distinguish two classes: those which spring directly from glaciers and those which rise in lakes, these being fed by eternal snows or glaciers. In the former class are the Isère, the Rhone, the Aar, the Ticino, the Tosa, the Hinter (or main) Rhine and the Linth; while in the latter class we have the Durance, the Po, the Reuss, the Vorder and middle branches of the Rhine, the Inn, the Adda, the Oglio and the Adige. The Piave and the Drave seem to be outside either class.
5. Principal Passes.—Though the Alps form a barrier they have never formed an impassable barrier, since, from the earliest days onwards, they have been traversed first, perhaps, for purposes of war or commerce, and later by pilgrims, students and tourists. The spots at which they were crossed are called passes (this word is sometimes though rarely applied to gorges only), and are the points at which the great chain sinks to form depressions, up to which deep-cut valleys lead from the plains. Hence the oldest name for such passes is Mont (still retained in cases of the Mont Cenis and the Monte Moro), for it was many ages before this term was especially applied to the peaks of the Alps, which with a few very rare exceptions (e.g. the Monte Viso was known to the Romans as Vesulus) were long simply disregarded. The native inhabitants of the Alps were naturally the first to use the alpine passes. But to the outer world these passes first became known when the Romans traversed them in order to conquer the world beyond. In the one case we have no direct knowledge (though the Romans probably selected the passes pointed out to them by the natives as the easiest), while in the other we hear almost exclusively of the passes across the main chain or the principal passes of the Alps. For obvious reasons the Romans, having once found an easy direct pass across the main chain, did not trouble to seek for harder and more devious routes. Hence the passes that can be shown to have been certainly known to them are comparatively few in number: they are, in topographical order from west to east, the Col de l’Argentière, the Mont Genèvre, the two St Bernards, the Splügen, the Septimer, the Brenner, the Radstädter Tauern, the Sölkscharte, the Plöcken and the Pontebba (or Saifnitz). Of these the Mont Genèvre and the Brenner were the most frequented, while it will be noticed that in the Central Alps only
