﻿486 M. A. Heim on Glaciers. 



developed granules of the neve. This development, consisting 

 in enlargement and (according to M. Grad) superadded "crys- 

 talline orientation" of the granules of the neve, it is to which 

 all the phenomena of the movement of the glacier are to be re- 

 ferred. Thus Hugi and M. Grad. The latter remarks, " Pro- 

 fessor Tyndall derives all the phenomena of the motion from 

 pressure; but this is erroneous;" of this erroneousness, how- 

 ever, he gives no proof, and as little on behalf of his own view. 

 Resting on the observation that the glacier-grain is larger 

 towards the lower part of the glacier than further up, and that 

 in the direction of the lower part of the glacier the structure of 

 its ice more and more approaches the crystalline condition of 

 water-ice, while the axes of the crystalline grains arrange them- 

 selves all parallel and perpendicular, he simply says it is so. 



Still more diverse are the results of the researches intended to 

 answer the question whether the network of capillary fissures 

 runs through the whole body of the glacier. Agassiz found the 

 capillary fissures even in the most compact glacier-ice. Schla- 

 gintweit infiltrated them with solutions of chromate of potassium 

 to the depth of 60 and 80 metres beneath the surface of the 

 glacier. MM. Bertin, Grad, and Dupre obtained results agree- 

 ing with the above. On the contrary, Hugi absolutely denies 

 the penetrability of the inner ice of the glacier ; and according 

 to Mr. Huxley's experiments, in sound unweathered glacier-ice 

 no capillary fissures exist. All have experimented very con- 

 scientiously ; but the results are diametrically opposite. Whence 

 comes this ? 



If the capillary fissures exist throughout the glacier-ice, but, 

 as must be the case in " sound blue " ice, are filled with water, 

 infiltration experiments cannot lead to any result ; for there is 

 nothing to cause the water to give place to the coloured liquid, 

 unless we have to do with a layer of ice beneath which the liquid 

 can freely run away, and on which there is the pressure from 

 above of a considerable column of the coloured liquid. It is still 

 more difficult to conceive that the infiltration through capillary 

 fissures, which the other observers assert that they have seen, 

 was a mere delusion ; for it is agreed that they also operated on 

 " sound " glacier-ice. In the parts of the glacier where great 

 pressure prevails, and so everywhere in the " structure mill" of 

 Professor Tyndall, the water in the capillary fissures, supposing 

 these to go through the whole glacier, is partly pressed out. In 

 these parts it will be impossible for the infiltration-liquids to 

 penetrate ; this will more easily be possible where the ice is sub- 

 jected to less pressure — for example, above declivities where 

 transverse fissures make their appearance, and in bends of the 

 valley, on the convex side of the body of the glacier. The dif-? 



