M. Charpentier oil the Glaciers of the Canton Vallais. 215 



stances, even extended beyond it ? How can we reconcile such 

 an hypothesis with the numerous facts which prove that, in for- 

 mer times, the temperature of our districts was much higher than 

 it is at present ? How can we believe in the former existence of 

 such prodigious glaciers in a tract of country which at one time 

 produced palms, as is proved by the occurrence of casts of a 

 chama^ops in the rocks of Lausanne and Vevay ? 



I acknowledge that these and many other objections present- 

 ed themselves, when, about five years ago, M. Venetz commu- 

 nicated this hypothesis to me for the first time. I remained 

 incredulous, until at length the facts which were zealously 

 sought for and examined to enable me to combat this opinion 

 led me to a very different result from the one I had anticipated, 

 and, above all, shewed me that the former existence of enormous 

 glaciers may harmonize perfectly with the facts which prove 

 that our climate was at an early period considerably warmer. 

 Before I endeavour to reconcile facts which are apparently so 

 incompatible, I shall first shew that all the phenomena exhi- 

 bited by deposits of these blocks and all the accompanying cir- 

 cumstances can be quite satisfactorily explained by the pro- 

 gressive movement of erratic blocks by glaciers. 



Wherever stones are deposited by glaciers, they are collect- 

 ed together and heaped up without order, and without any 

 separation according to size and weight. The largest blocks 

 are mixed with gravel and grains of sand, and all are trans- 

 ported to an equal distance. Thus the alluvial masses formed 

 by glaciers present exactly that want of separation of the indi- 

 vidual stones according to size and weight which we observe in 

 deposits of erratic blocks, and there is thus nothing remarkable 

 in finding on the Jura blocks of the same size as those occurring 

 at the foot of the Alps and in the valleys. 



The flowing off of the water is sometimes prevented by 

 glaciers and moraines, so that at their sides small lakes are 

 formed, in which stones, sand, and mud are deposited by the 

 streams. It is therefore not surprising to find associated with 

 the alpine blocks small layers of such materials, which appa^ 

 rently have been deposited and stratified by means of the water. 



Although most of the stones transported by the glaciers are 

 rounded, or at least have the angles and edges more or less 



