Page:Encyclopædia Britannica, Ninth Edition, v. 8.djvu/717

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Since the city of Rome has again become the capital of Italy the attention of the Italians has been specially turned to the Tiber, and several schemes of Herculean magnitude have been discussed. Garibaldi s project was adopted by both houses of the Parliament and sanctioned by the Government in 1875. During the present century the Danube, which is the most international of European rivers, has been greatly improved as a water-way, by the rectification of its course in the neighbourhood of Vienna, by the clearing of the passage of the Iron Gates, and by the maintenance of a proper channel at the delta. It is almost needless to mention the works that have been carried on for the deepening of the seaward section of all the greater rivers, and the removal of the bars at their mouths ; perhaps in this department the most .remarkable results are exhibited by the Clyde. In the accompanying table, for which we are indebted to Glogau, the principal lakes of Europe are arranged according to their size. If we examine their distribution we find they can easily be classified into groups. The Name of Lake. Country. Height above sea. English ft. German sq. miles. English sq. miles. Russia i 413-00 228-59 99-50 51-31 4970 47-30 45-00 42-26 35-40 25-25 21-40 21-39 1990 19-50 1910 18-00 17-30 16-79 10-50 14-90 14-32 11-20 9-60 9-10 8-92 8-90 8-20 722 6-60 650 5-50 5-34 4-96 4-36 417 3-70 3-62 3-20 2 90 8780-66 4855-73 2115-43 1090-88 1050-05 1005-03 956-73 898-47 752-62 53683 454-97 454-70 423-08 414-58 400-07 382-09 367-81 350-96 350-80 316-78 304-45 238-11 204-10 193-47 189-64 189-22 174-33 153-50 140-32 138-19 116-93 113-53 105-45 92-69 88-65 78-66 76-96 68-03 61-65 Sweden 140 96 405 256 Peipus Enire Russia Sivosh 261 282 123 33 Wetter . ... Sweden Malar Ri>.-lo Ozero Russia Pielis 30 1 Platten Hungary 457 390 107 Uleo Ilmen Store Luleo-Wattnen . Stor Afyan 843 Pskoff . Russia Geneva France and Switz- ) 1230 1342 984 1305 92 545 48 227 411 367 Sweden Stor Sjo Boden-See Germany Siljan . Ireland Garda Mjijsnn Neusiedler Italy Norway Hungary Turkey 115 1426 Ncufcl a el Talpukh Switzerland Lago Maggiore Italy Russia 040 918 30 700 Ireland Tt-silv ... i Alpine lakes break up into a southern and northern subdivi sion the former consisting of Lago Maggiore, Lago di Como, Lago d Iseo, and Lago di Garda, all connected by affluents with the system of the Po ; and the latter the lake of Geneva threaded by the Rhone, Lakes Constance, Zurich, Neufchatel, Biel, and other Swiss lakes belonging to the basin of the Rhine, and a few of minor importance belonging to the Danube. As factors in the historical development of the Alpine countries the first rank must be assigned to Geneva, Constance, and Como. Next in interest to the Al pine group comes the Swedish Wener, Wetter, Malar, and Iljelmar, lying between the Baltic Sea and the Skagerrack, and nearly as famous as their Scotch and English rivals for tin- beauty of their scenery. The North Russian lakes, Ladoga, Onega, o., are mainly noticeable as the largest members of what in some respects is the most remarkable system of lakes in the continent the Finno-Russian, which consists of an almost countless number of comparatively small irregular basins formed in the surface of a granitic plateau, "in Finland proper they occupy no less than a twelfth of the total area. It is impossible to take individual 687 account of the multitudinous small lakes that diversify the surface of every country in Europe, with the partial excep tion of Spain ; but their influence on the climate and hydrography of the continent must not be overlooked. All of them help to increase the area of evaporation, and many even of those which are almost nameless act as reservoirs for rivers. Nearly all the rivers of Sweden, for example, have their origin in a lake or tarn ; and the same is the case with many of the streams of the northern Pyrenees. The total area of the lakes given in the table is no less than 28,450 square miles, or about the united area of the Nether lands and Switzerland. A few of the number are very shallow. The Neusiedler See, for example (the Peiso Lacus of the Latins and Fertotava of the Hungarians), completely dried up in 1864, and left its bed covered for the most part with a deposit of ea t. 1 Others not mentioned in the table have been partially or com pletely drained by human labour. The Copais in Bceotia was attacked by Greek engineers as early as the time of Alexander the Great; but the tunnels which they con structed to carry off its waters have been choked up, and the lake is again in a state of nature. Lake Fucino or Lago Celano, in the Abruzzo in Italy, was doomed to destruction by the emperor Claudius; but the works which he con structed proved ineffectual, and it was not till 1862 that a large part of the basin was turned into dry land. The progress of agriculture has greatly diminished the quantity of marsh land in Europe, and there are only one or two really extensive regions which deserve the name. Most important of all are the Minsk marshes in Russia, and on these large encroachments are gradually being made. The draining of the Pomptine marshes in Italy made Pope Pius VII. famous in the 18th century; and at the present moment those of Ferrara are sharing the same fate. Geologists have as yet come to no agreement regarding Goolopi- the origin of the principal mountain ranges, and still less do OT they furnish a consistent and connected history of the shaping of the continent. It will consequently be sufficient to indicate the general distribution of the various forma tions, and the more important basins of deposition for the sedimentary rocks. 2 The typical basin is that which takes its name from Paris : in it the successive stratifications are arranged in an exceptionally symmetrical manner. To the south-east lies the basin of Bordeaux, separated by a plateau of granite and gneiss ; to the north, on the other side of the Channel, the London basin ; and to the north east the basin of the lower Rhine. Further east conies the basin of the lower Weser, divided into two almost in dependent portions by the Harz mountains ; and to the south-east is the Prague basin, which presents only frag mentary remains of its sedimentary deposits. Nearly the half of European Russia belongs to the Moscow basin, which, in the south-east, is conterminous with the probably more modern basin of the Caspian. The whole of the south of the continent, from the Pyrenees to the Caucasus, belongs to the Mediterranean basin, which is one of the greatest in the world, and has its northern limit marked by the Cevcnnes, the Jura, the Thiiringerwald, the Bb hm- erwald, and the Arratyne plateau. The total surface area occupied by the plutonic and metamorphic rocks is far from inconsiderable ; but, with the exception of the great mass of the Scandinavian peninsula, Finland, and Lapland, and the long line of the Urals, the individual portions are of comparatively small extent. In the Spanish peninsula they stretch from Corunna south to the Tagus, appear again in the neighbourhood of Evora, form the western part of the Sierra Guadarrama, and rise in islets above the Silu- 1 See Ascherson, "Die Anstrocknung des Neusiedler Sees," in Z, der Gcs. ftir KrdkunJe zu Berlin, 1805.

  • See map in Petermanu s Mittheilungen, 1873.