CHAP. XV. NOT DUE TO FLOATING ICE. 301 



direction, was ascertained by Charpentier, from its com- 

 position, to have been derived from n, one of the highest 

 points on the left side of the Ehone valley, far above 

 Martigny. From this spot it must have gone all round by f, 

 which is the only outlet to the deep valley, so as to have 

 performed a journey of no less than 150 miles ! 



General Transportation of Erratics in Switzerland due to 

 Glaciers and not to floating Ice. 



It is evident that the above-described restriction of certain 

 fragments of peculiar lithological character to that bank of 

 the Rhone where the parent rocks are alone met with, and 

 the linear arrangement of the blocks in corresponding order 

 on the opposite side of the great plain of Switzerland, are 

 facts which harmonize singularly well with the theory of 

 glaciers, while they are wholly irreconcilable with that of 

 floating ice. Against the latter hypothesis, all the arguments 

 which Charpentier originally brought forward in opposition 

 to the first popular doctrine of a grand debacle, or sudden 

 flood, rushing down from the Alps to the Jura, might be 

 revived. Had there ever been such a rush of muddy water, 

 said he, the blocks carried down the basins of the principal 

 Swiss rivers, such as the Ehone, Aar, Eeuss, and Limmat, 

 would all have been mingled confusedly together instead of 

 having each remained in separate and distinct areas as they 

 do and should do according to the glacial hypothesis. 



M. Morlot presented me in 1857 with an unpubhshed map 

 of Switzerland in which he had embodied the results of 

 his own observations, and those of MM. Guyot, Escher, 

 and others, marking out by distinct colors the limits of the 

 ice-transported detritus proper to each of the great river- 

 basins. The arrangement of the 'drift and erratics thus 

 depicted accords perfectly well with Charpentier's views, and 



