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these heights than in the valley, and I have no hesitation in saying 

 that in winter very little snow falls upon the higher summits. The 

 snow-falls in the valley are invariable/ brought by a low creeping 

 fog, which comes up from Sallanches. It seldom overtops the Col 

 de Voza, and the Aiguilles appear bright and sunny in the gaps of 

 the cloud. It is in spring and autumn that these higher peaks are 

 powdered by every storm ; now the dispersing clouds leave them 

 as dark as before they gathered. I fancy this winter is unusually 

 cold ; every one is crying out, and complaining that the potatoes 

 are frozen in deep cellars. I have seen Reaumur's thermometer at 

 — 25° at 5 J in the afternoon, and I think it may reasonably be 

 supposed that it may have fallen to — 30° during the night; wine 

 has frozen on my table before a fire. In the woods the trees crack 

 with the intense frost, and there is from 2J to 3 feet of snow in the 

 valley without drifts ; on the glacier of Blaitiere there is only from 

 1 to 2 feet. 



" In spite of all this cold the glaciers advance steadily. The gla- 

 cier de Blaitiere, terminating above the line of trees, pushes its 

 moraine in front of it, and seems to be on the increase. Now this 

 is a very shallow glacier, and, as I have said, covered with but 

 little snow. Is it possible that infiltrated water can have any action 

 whatever under such circumstances ? 



" I will here state a few results of careful observation, and I hope 

 that, even should they appear strange, you will yet consider them 

 worthy of confidence. I have no theodolite, but I have a pris- 

 matic compass, and will take the bearings of various points from my 

 stations should you deem it advisable. 



" The torrent of Bossons has been quite dry ever since the begin- 

 ning of November, and I have profited by this circumstance to en- 

 deavour to determine the motion of the ice within the vault, nearly 

 in contact with the ground. I believe it is usually supposed that 

 the reason why the termination of a glacier seems stationary in 

 summer, is that there the waste predominates over the supply. It 

 seemed to me, therefore, that in winter, when there is actually 

 no waste — the torrent being perfectly dry, and its subglacial bed 

 even dusti/-— the end of the glacier ought to be thrust forward into 

 the valley by the pressure behind. I accordingly, with some little 

 difficulty, fixed a station on the ridge or back of the glacier, near 

 the lower extremity; the result is, that the ice there is nearly sta- 



