x.] ALPINE TRAVELS, 1846. 321 



presenting hardly any bands, cither vertical or horizontal ; 

 and tliis is true even so low down as my line of stations 

 across the glacier, not far above the icefall. From this 

 I gather : 



1 1. That the vertical structure comes too near the neve 

 proper, to admit of its phenomena being explained by 

 a shifting of the strata of the neve, through an angle 

 of 90. 



-2. That, when the vertical veined structure is not 

 loped, the horizontal layers have vanished, and are 

 not yet replaced by another structure. 



' 3. That the conversion of neve into ice, is simulta- 

 neous and identical with the formation of blue bands. 



1 4. That these bands are formed where the difference 

 of motion is at its maximum, that is, near the walls of 

 the glacier ; but being once formed, they still continue to 

 show themselves under the medial moraine, and this may 

 be traced in the centre of the icefall of the Taldfre. 



' 5. Its generally imperfect development accords with 

 the slowness of the absolute motion. 



' Whilst on this subject I may mention that the 

 appearance of the crevasses between the Montanvert and 

 Tivlaporte confirm exactly my observations of previous 

 years at this season. The falling together of the glacier, 

 the undulating forms of the angles of the crevasses, and 

 the choking of crevasses by falling together, all betoken 

 plasticity in the plainest manner. In particular, I had an 

 opportunity of watching individual crevasses opposite the 

 MontaiiYcrrr, and what I saw incontestably showed that 

 th< crevasses were then widening without tearing at 

 bottom, whilst the surface was losing at once by ablation 

 and subsidence of the masses forming the walls/ 



After M f.-w days occupied in various experiments, 

 'cs, accompanied by Pa 1m at, passed round by the Col 

 du Ikmhomme to the other side of the chain for the pur- 

 pose of re-examining the glaciers of Brenva and Miage, 

 in o .. li< ther tin- freshly dl8CQV< red pheii..ii' 



of tli* M uted by them al><>. 



Y 



