272 APPENDIX, NO. V. 



out, and complaining that the potatoes are frozen in deep cellars. I 

 have seen Reaumur's thermometer at 25 at 5|- 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 glacier 

 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 ? 



11 1 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 prismatic 

 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 beginning 

 of November, and I have profited by this circumstance to endeavour 

 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 sub-glacial bed even dusty 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 stationary. This is doubtless a clue to the 

 assertions of some authors, "that the glacier is stationary in winter;" 

 they only looked at the end. What becomes, then, of the ice con- 

 tinually descending from above ? Does it not go to thicken the whole 

 mass, accumulating behind the more rigid portion below, as water 

 behind a dam ? I have no space to add more at present, but will 

 write again if I have your approval of my proceedings. Meanwhile 

 I have fixed (yesterday) an intermediate station, for the purpose of 

 determining where this comparative immobility begins. I have noted 

 my observations, and kept a register of weather, etc. I give one 

 * [See note to next page-1 



