212 Prof. Favre on the Origin of 



valleys, before, during, and after the glacial epoch, than in the 

 valley of the Lake of Geneva. 



The valleys of Savoy and the Valais bear a clear relation to 

 the structure of the mountains. They present a remarkable 

 regularity. They are nearly all at right angles to or parallel 

 with the general direction of the Alps. Amongst the former 

 cases is noticed the valley of the Rhone from Martigny to the 

 lake ; that of the Dranse, which has its outlet near Thonon ; 

 that of the Arve, from Sallanche to Geneva ; the valley of Lake 

 Annecy; that of the Isere between Moutier and Albertville, 

 and between Tigne and Bourg St. Maurice, the valley of 

 Chapier, that of Courmayeur, &c. Amongst those which are 

 parallel with the chain of the Alps, are the valley of the Rhone 

 above Martigny, the valley of Chamouny, of the Allee-blanehe 

 and Entreves, the valley of Uliers, the valley of Megeve, and 

 that of the Isere below Albertville, and between Bourg St. 

 Maurice and Montiers. 



Amongst these may we not reckon the depression in the Lake 

 of Geneva between that town and Rolle, and which is parallel 

 to the great anticlinal axis of the Mollasse ? This axis extends 

 from Saleve to Lausanne, passing by Boisy, and is continued 

 onwards to Bavaria *. As to the eastern parts of the lake, the 

 direction of which is from west to east, slightly south-east, and 

 which is considerecLwith reason as being partly placed in a depres- 

 sion {cluse), it bears a relation to the curved form of the mountains 

 which lie on its southern bankf. To prove this, it is necessary 

 to enter into minute details with regard to the direction of the 

 various parts of the chain, which would be out of place here ; 

 but I may quote an old and classical authority that nobody will 

 call in question, and this quotation will show that the lake 

 presents nearly the form of the mountains. " The ordinary 

 direction of these ranges and of these valleys," says De Saussure J, 

 when speaking of the region lying on the right bank of the 

 Arve (between the Arve and the Rhone), "is nearly that of the 

 entire chain, which in our country extends from the north-east 

 to the south-west. But this general direction varies in some 

 places and undergoes local inflexions. One sees from the 

 summit of the Mole that the chains of mountains, which in its 



* Bull. Soc. Geol. de France, 1864, vol. xix. p. 928. Arctrives, 1862, 

 vol. xiv. p. 217- 



f It is not on the south bank only of the Lake of Geneva that the 

 chains of mountains assume a circular or semicircular outline. This form 

 is still more developed in the mountains of the left bank of the Arve than 

 in those of the opposite bank. See, in reference to this subject, a note 

 which I have published in the ' Reports of the British Association for the 

 Advancement of Science,-* 1860 (Trans, of Sect., p. 78). 



% Voyages, § 280. 



