EUROPE 685 Their mean elevation is about 5000-5600 feet ; but it is only from the southern side that they present a really mountainous appearance ; on the northern they gradually descend by a succession of terraces, and, with few excep tions, the summits have gently rounded contours. The culminating point is Tchar Dagh, which rises to a height of about 9700 feet. Connected with the Balkans by its western extremity is the range of the Despoto Dagh, or Rhodope, which stretches eastward along the north of the yEgean, and in some points reaches a height of 8000 feet. Nearly the whole country to the south in Thessaly and Greece is occupied by irregular groups and lines of moun tains and hills, among which the most important are the Pindus and Olympus. Besides the Alpine system and the secondary systems which are grouped along with it, there are several others rendered quite distinct by their position and structure. The Pyrenees are next to the Alps in elevation. They extend across the isthmus between France and Spain for a distance of 240 miles, and are practically con tinued by the Cantabrian Mountains for 260 miles more. The loftiest summit, Mont Perdu, has an altitude of 11,270 feet. The south side of the Pyrenees proper is the more rugged and precipitous ; but the Cantabrian Mountains present their steepest face to the north. All the minor mountain ranges of Spain are connected with each other and with the Pyrenees. The highest is the Sierra Nevada in the south. The chain of the Dovre-Fjeld, Dofrines, or Scandinavian Alps is about 1000 miles in length, and has a general elevation of from 3000 to 6000 feet. Properly speaking, it is not so much a range of mountains as a plateau, broken up by deep-cut ravines and fiords. The western side is precipitous, and the eastern de scends gradually to the Gulf of Bothnia. The Urals-extend from north to south through 20 of latitude, with a breadth of about 40 miles. They rise slowly from the plain on both sides, and at the place where they are crossed by the road from Moscow to Siberia the ascent and descent is hardly noticeable. A considerable proportion of the range lies between 3000 and 4000 feet above the sea ; a few peaks attain an altitude of 5000 ; and one, Toll-pors, is not much under 5500. 1 If the European mountains are arranged according to their greatest elevations, they rank as follows : (1) the Swiss Alps, with their highest peaks 15,000 feet or upwards; (2) the Sierra Nevada, the Pyrenees, and Etna, about 11,000 feet ; (3) the Apennines, the Corsican Mountains, the Car pathians, the Balkans, and the Despoto Dagh, from 8000 to 9000 ; (4) the Guadarrama, the Scandinavian Alps, the Dinaric Alps, the Greek Mountains, and the Cevennes, between 6000 and 8000 ; (5) the mountains of Auvergne, the Jura, the Riesengebirge, the mountains of Sardinia, Majorca, Minorca, and the Crimea, the Black Forest, the Vosges, and the Scottish Highlands, from 4000 to 6000. The table given on page 686 furnishes a comparative view of the principal European streams taken in the order of their length. In various parts of Europe, more particularly in cal careous regions, there are subterranean or partially subter ranean rivers. Of these the most remarkable are the Sorgue of Vaucluse, the Touvre of Angouleme, the Timavo of Istria, and the Poik or Planiua. The first has been traced for 10 or 15 miles below ground; and the Tiinavo when it issues from the mountain is already navigable. Along the French coast several subterranean affluents of the Mediterranean have been discovered, and some of them are evidently of considerable size. The Garonne itself, which rises in the glaciers of Mount Maladetta, passes 1 Cf. "Protil den Ural-Uebirges," iu Zeitschr.fur Erdkunde zu Merlin, 1 58. under Mout Poumar for a distance of 4 kilometres. The subterranean course of the streams is frequently indicated by peculiar vents or pits caused by the subsidence of the soil ; they are popularly known in Greece as catavothra, in Carinthia as dolinas, aud in France by a great number uf local names, such as cmlacs, gr/urys, loit-tout, anselmon*, fcc. 2 Europe has no Niagara, and, indeed, few of its larger rivers present anything approaching to a real cataract. The Rhine takes a plunge of about 50 feet at Schaffhausen ; and there are a series of rapids in the lower course of the Dnieper and the Dniester. In Sweden the Gotha-Elf falls 100 feet at Trollhata; the Hjommel Sayka or Hare s leap of the Lulea is 250 feet high ; and the Riukan Fos or " Smoking Force " at Mjosvand is no less than 800. The famous Staubbach in the neighbourhood of Lauterbrunnen has a descent of 980 feet, but it is a mere brook, and in summer almost dries up ; it takes its name, as is well known, from the dust-like appearance of the spray into which the water is changed by the tremendous descent. Several of the more important rivers are of very irregular flow, and some are subject to really formidable floods. In 1877 there were disastrous inundations of the Danube : 12,000 people w^re rendered homeless in one of the suburbs of Buda Pesth, hundreds of houses were undermined, while villages were submerged, and large quantities of property were swept away. The floods in the Netherlands the same year were severe enough to necessitate Government help for the sufferers. Large areas in Saxony and Silesia were under water; the Elbe, the Vistula, the Nogat, and the Oder, all overflowed their banks or burst their dikes, it was feared that the whole line of railway between Thorn and Posen would be carried away, and in some districts there was considerable loss of life. If all the damage produced in this way since the beginning of the cen tury could be calculated, it would be found to repre sent an enormous sum. The floods of the Loire alone, in 1856, carried off about 8,000,000 worth of pro perty; and those in the south of France in 1875 caused a loss of about 3,000,000. In most Continental countries there have been consequently undertaken extensive en gineering works, partly to prevent inundations, and partly to render the rivers more serviceable for navigation and irrigation. France has been especially active in this matter, several of her most important streams being very difficult to regulate. The Loire, for example, varies at Orleans from 25 cubic metres or 780 feet per second to 10,000 metres or 315,000 feet in the same time ; the Saone, in 1855, varied from 3,825,450 cubic feet per minute to 174,086; and the Rhone at Geneva, in 185S, which was a minimum year, from 740,000 cubic feet to 195,000. 3 The engineering works have been especially successful on the Seine and Yonne, where several new methods have been tested fen- storing the surplus water of one season, and utilizing it during the period of deficient supply. 4 In Italy the Po, the Arno, and the Tiber are notorious for their floods; but the first two are now among the most striking examples of a satisfactory system of embankment. At Cremona, on the Po, which is 171 miles inland and 104 feet above sea-level, the flood of 1840 rose 18 feet, that of 1855 rose 19 feet, and that of 1857 20 feet, above summer low- water. On the last occasion the banks above Cremona were burst, and avast area of country was submerged; but such a disaster is now comparatively rare. For the irrigation of the Lom bard plain no less than 702,838 cubic feet per minute aro drawn off by the canals. See E. Reclus, La Terre, vol. i. 3 See Beardmore s Manual vf Hydrography, 1862. 4 See Blerzy, (i Stoles sur les travaux publics," in Revue des Deux
Mondes, 1875.