284 A Week among the Glaciers. 



manner of farmers in setting a post and rail fence) along the 

 smooth faces of the stones which were turned towards the sum- 

 mit of the mountain. I then had three other stones carried on 

 the glacier at the distance of fifty to sixty feet from each other, 

 and placed in a straight line with the three former stones, and 

 left them to mark the change which should take place in their 

 relative positions, on my return. 



A similar experiment I made in the evening on my arrival at 

 the Grand Millets, and on my return to the Grand Mulets the 

 next day at 1 o'clock, P. M., and at the point where I had made 

 the first experiment at 4 o'clock, P. M., which made nineteen 

 hours for the former, and thirty one for the latter. The stones 

 on the glacier had descended during this time, from a line drawn 

 from the upper surface of the stones on the mountain to the up- 

 per surface of the stones on the glacier, between twelve and thir- 

 teen inches for the former, and about twenty one inches for the 

 latter, which is about sixteen inches for the twenty four hours. 



The number of pulsations and respirations per minute, of the 

 whole party, I had taken at Chamonix, previous to leaving, and 

 found that the average was seventy six of the former and sixteen 

 and a half of the latter. At this point, the perpetual snow line, 

 there was a slight acceleration, the respirations being eighteen 

 and the pulsations eighty two per minute, after resting fifteen 

 minutes, and of course previous to eating, as the pulsations are 

 augmented during the process of digestion. 



At 10 o'clock, A.M. we entered upon the glacier; the travel- 

 ling was at first neither difficult nor fatiguing, for we had each a 

 well tried Alpenstock, which was equal to a third foot in case of 

 need, and our shoes, made for the occasion, were well armed with 

 square-headed nails throughout the whole extent of heel and sole. 



The extreme purity of this glacier is remarked by all as greater 

 than that of either of the other glaciers in the valley of Chamo- 

 nix, and its crevasses present most perfectly the bluish green, 

 and from that to the deep blue of the gulf water. The crevasses 

 in this glacier are much deeper, wider, and more extensive, than 

 either of the others in this valley ; and this is owing probably to 

 its great extent, and to its being one of the most precipitous of 

 the Alps. They vary in width from a few feet to many hun- 

 dred, and taking their length, including their windings, from a 

 few rods to one or two miles. Their depth has been estimated 



