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Keport of the Researches of M. Agassiz during his two last 

 sojourns at V Hotel-des-Neuchatelois, upon the Lower Glacier 

 of the Aar, in the years 1841 and 1842. By M. E. Desor. 



(Continued from page 178.) 



1. Experiments on Infiltration. 

 The theory of infiltration admits that the water produced 

 by superficial melting does not altogether escape by the inter- 

 nal cavities or the terminal openings of the glacier ; and that 

 a considerable portion of it penetrates into the interior, is 

 there congealed, and so contributes partially to supply the 

 loss which the glacier undergoes at the surface. This water 

 percolates throughout the whole mass of the glacier, by means 

 of a general net-work of capillary fissures, which fill the larger 

 basins, the hollows of pools, cascades, &c., in the same man- 

 ner as the minute blood-vessels supply the larger trunks in the 

 living body. This net-work of minute fissures is so evident 

 at the surface, that it admits of no doubt or dispute ; but, as 

 formerly remarked, the opinion that the same arrangement 

 pervades the whole mass, has been much contested. Hence 

 it became necessary to devise some method whereby the fact 

 might be ascertained ; and this, it appeared, might be satis- 

 factorily done by the introduction of coloured liquids into the 

 ice : for, if the dye coloured the ice to a certain depth, a proof 

 would be afl^orded that the capillary fissures reached to the 

 same extent. Accordingly, M. Agassiz brought along with 

 him a barrel filled with a highly concentrated infusion of log- 

 wood, kindly prepared by M. Henri Du Pasquier, and also a 

 quantity of chromate of potash, both of which are intense 

 colours, without being expensive. We began by boring at 

 the margin of a canal cut by the running stream near the 

 Hotel-des'Neuchatelois a couple of holes about two feet deep. 

 Into each of these we poured about a quart (litre) of the in- 

 fusion of logwood, and in half-an-hour we perceived that the 

 wall of the ice was discoloured in front of one of the holes, 

 and to the depth of a foot beneath the lowest part of the ex- 

 cavation, and ere long the dye percolated from all the capil- 



