310 



the chalk and the commencement of the tertiary groups ; and the cor- 

 responding change in organic types is, in this instance, still more 

 striking than in the former. 



3. The third system embraces a great number of parallel inequa- 

 lities, bearing about north-north-east and west-south-west, and in- 

 cludes the whole Western Alps, from the neighbourhood of Marseilles 

 to the volcanic ridges near the foot of the Lake of Constance. And 

 by an hypothetical, but I think probable extension, it also takes in the 

 whole of the great Scandinavian chain. 



I cannot enter on the elaborate and satisfactory details by which 

 it is proved — that all these great parallel inequalities in the region of 

 the Western Alps had their origin after the tertiary molasse, a deposit 

 partaking of all the elevations and contortions of the older strata — 

 that the elevatory movements were sudden and violent, and com- 

 menced at a time when tribes of mammalia (the remains of which 

 in England are hardly ever found except in the superficial gravel) 

 flourished in many parts of Europe — and that these movements were 

 immediately succeeded by great horizontal deposits of old diluvial 

 gravel at the base of the Western Alps, and probably also by that 

 vast offshot of Scandinavian rocks which lie scattered over the 

 northern plains of Germany. 



4. The fourth system embraces many great parallel ridges having 

 a range about east-north-east and west-south-west, and includes 

 several considerable chains in Provence, and nearly the whole chain 

 of the Eastern Alps — from the great flexure in the region of Mont 

 Blanc to the Alps of the states of Austria. 



It would be impossible to follow the author through details occupy- 

 ing a large portion of his volume. I may however state, that he proves 

 the formations of the Eastern and Western Alps not to pass into each 

 other by any flexure of the strata coinciding with the bend of the 

 whole chain; but to meet at an angle marked by a great double system 

 of breaks and fissures, one passing in the direction of the eastern, 

 and the other of the western portions of the chain. He further proves, 

 that the system of fissures in the line of the Eastern Alps is more 

 recent than the other system — that in the prolongation of this line 

 towards the west, the old diluvial gravel has undergone movements 

 of elevation — and that these movements have been propagated to the 

 lacustrine and volcanic regions of Auvergne. 



On a review of the whole evidence, I think he has demonstrated, 

 that there are two distinct deposits of diluvial gravel near a portion 

 of the Western Alps — that the colossal mass of Mont Blanc, and at 

 least a considerable portion of the Eastern Alps, were elevated after 

 the deposit of the older diluvium — and that the newer diluvium (in- 

 cluding all those enormous crystalline erratic blocks so admirably 

 described by Saussure ) rolled off from the regions of the higher Alps 

 during this last period of their elevation. 



There are six other supposed periods of elevation briefly considered 

 in the researches of M. Elie de Beaumont, each marked by distinct 

 geographical features : but I will not now detain you with their enu- 

 meration. If the generalizations to which I have pointed be true, 

 and, as far as I comprehend them, they seem to be based on an im- 



