1846.] THE CONVERSION OF THE NEVE INTO ICE. 199 



(2.) ON THE CONVERSION OF THE NEVE INTO ICE. 



I shall now add a few observations tending to throw light on 

 two of the most obscure glacial phenomena, first, the conversion 

 of the snow of the Neve into pure ice, and, secondly, on the 

 apparent ejection of stones from the surface of the glacier. 



On the first point, I made some interesting observations 

 on the higher part of the Glacier du Geant, where the still 

 snowy ice, marked with the horizontal annual strata, is shoved 

 violently down the steep, which occasions the scene of desolate 

 confusion between the Aiguille Noire and the rock called Le 

 Petit Rognon. The structure of the interior of the embryo 

 glacier is here perfectly disclosed by the prodigious vertical 

 rents which make the scene a true giant's staircase ; the ice- 

 falls succeeding one another at regulated intervals, which appear 

 to correspond to the renewal of each summer's activity in these 

 realms of almost perpetual frost, when a swifter motion occasions 

 a more rapid and wholesale projection of the mass over the 

 steep, thus forming curvilinear terraces like vast stairs, which 

 appear afterwards, by consolidation, to form the remarkable 

 protuberant wrinkles on the surface of the Glacier du Geant 

 described in my Fifth Letter. But the point which at present 

 concerns us is this, that, according to the best observations 

 which I could make, the stratified appearance of the Neve dis- 

 appeared at a depth inconsiderable compared to the vast vertical 

 sections there exposed, and the interior of the mass was granular, 

 and without structure or bands of any kind. 



I drew the very same conclusion from an attentive survey 

 of the Glacier de Talefre, which is peculiarly calculated to throw 



* It is not unimportant for travellers to be aware that in seasons like 1846, 

 of unusual warmth and activity amongst the glaciers, the dislocation and pre- 

 cipitous subsidence of the tabular masses of the Neve is occasionally so complete 

 as absolutely to debar a passage, at least without the help of a ladder. This 

 was the case when I ascended the Glacier du Geant on the 14th August last, a 

 snow bridge by which some travellers had effected a passage a fortnight before 

 having wasted away. Had travellers at that time crossed the Col du Geant 

 from Courmayeur to Chamouni, they might have found their descent, if not 

 impracticable, at least most perilous, and to return from such a distance would 

 have been an almost equally distressing alternative. On this account it is most 

 advisable to make this passage from the side of Chamouni. 



