ft02 METEOROLOGY. 



geographer shows, that precisely in the situation where the Alghinic 

 mountains are usually set down, a remarkable region of lakes com- 

 mences, which extend into the plains that are traversed by the Ichim 

 the Omsk, and the Obi.* It would appear that these numerous 

 lakes are remainders as it were of an immense sheet of water, which 

 formerly covered the whole of the country, and which had become 

 divided into so many particular lakes by the configuration of the 

 surface. In crossing the steppe of Baraba, in his way from Tobolsk 

 to Baraoul, M. de Humboldt perceived everywhere that the drying 

 up of waters increases rapidly under the influence of tile cultivation 

 of the soil. 



Europe also possesses its lakes ; and we have still to examine 

 them from the particular point of view which engages us. M. de 

 Saussure, in his first inquiries in regard to the temperature of the 

 lakes of Switzerland, examined those which are situated at the foot 

 of the first line of the Jura. The Lake of NeufchS.tel is eight 

 leagues in length, and its greatest breadth does not exceed two 

 leagues. On visiting it, Saussure was struck with the extent which 

 this lake must formerly have possessed ; for, as he says, the ex- 

 tensive level and marshy meadows which terminate it on the south- 

 west, had unquestionably been covered with water at a former 

 period. 



The Lake of Bienne is three leagues long and one broad ; it is 

 separated from the Lake of Neufch^tel by a succession of plains that 

 were probably inundated. 



Lake Morat is also separated from the Lake of Neufch4tel by low 

 and level marshes, which beyond all question were formerly sub- 

 merged. Unquestionably, adds Saussure, the three great lakes of 

 Neufch^tel, Bienne, and Morat, were formerly connected, and formed 

 one great sheet of water.f 



In Switzerland, as in America and Asia, the old lakes, those thai 

 may be spoken of under the title of the primitive lakes, and which 

 occupied the bottoms of the valleys when the country was unculti- 

 vated and wild, have become divided, and now form a variable num- 

 ber of smaller and independent lakes. I shall wind up the present 

 subject by referring to the observations of Saussure upon the Lake 

 of Geneva, which may be looked upon as the starting point of the 

 admirable works of this distinguished philosopher. 



Saussure admits, that at an epoch long anterior to the times of 

 history, the mountains which surround this lake were themselves 

 submerged ; a great catastrophe let off this immense collection of 

 water, and by and by the current possessed no more than the bottom 

 of the valley ; the Lake of Geneva was formed. 



In merely considering the monuments left by man, it is impossible 

 to doubt that within 1200 or 1300 years the waters of the Lake of 

 Geneva have gradually fallen in their level. It is evidently upon 

 the levels which have thus been left that the quarter de Rive, and 

 the lower streets of the city of Geneva have been built. This de 



 Humboldt, Fragmens Asiatiques, t. i. p. 40-50. 

 t Saussure, Voyage dans les Alpes, t. ii. chap. 6. 



