160 



GERMANY. 



its boundaries are ill defined, and it forms no unit in the configuration of Europe, 

 as does Spain, England, France, Scandinavia, or Prussia. The limestone Alps of 

 Bavaria are a continuation of those of Yorarlberg and Appenzell. The geological 

 formations which fill up the great miocène sea of Switzerland can be traced into 

 Southern Bavaria, where they are in great part concealed below the débris 

 deposited 1 y glaciers. The Jura extends through Swabia and Southern Germany 

 as far as the western corner of Bohemia. The Black Forest, with its granite, red 

 sandstone, and triassic rocks, corresponds with the Vosges on the other bank of 

 the Rhine, and the platform upon which it rises extends northward as far as the 

 plain of Hanover. The rocks on both sides of the Rhine, below Mayence, are of 

 the same aire. The Devonian formation of the Ardennes stretches to the north-east 



Fig. 94. — The Lsothermal Lines of Germany. 

 Accordine to Putzger. 



into Nassau and Westphalia, and is bounded in the north by carboniferous forma- 

 tions, in the centre of which the plain around Cologne opens out like a vast bay. In 

 Belgium, as in Gr'ermany, the most advanced hills are capped with chalk, or rocks 

 belonging to more recent formations. Finally, there is the vast northern plain, 

 covering an area of 150,000 square miles, which merges, on the one hand, in the 

 plain of Holland, and, on the other, in that of Poland and Russia. Geologically 

 Germany thus consists of two distinct portions, the south being joined to Switzer- 

 land, France, and Belgium, whilst the north is a westerly extension of the great 

 Sarmatian plain. 



Volcanic hills are numerous in Central Germany, to the north of the Moselle 

 and the Main, the craters of some of them being filled with small lakes. They 

 are the standing witnesses of a time A\hen fiery lava burst forth from volcanoes 



