Besearches on Existing Gldciers, 265^ 



cascades and even jets similar to that of a fountain, as was 

 well seen last year in the glacier of the Rhone ; but most fre- 

 quently their opening is very small, and is hardly a line in 

 diameter ; they then give rise to small stalactites, of which I 

 shall afterwards speak. 



3. By capillary fissures, which divide the whole mass into 

 a quantity of angular fragments of various sizes. We may 

 assure ourselves of this by pouring, as I have done, coloured 

 liquids into cavities hollowed out at the surface of the glacier. 



4. Lastly, it seems to me probable that the vertical bands of 

 blue compact ice, alternating with bands of white porous ice, 

 and which I shall discuss immediately, maintain a continual 

 infiltration of^vater in the mass of the glacier wherever this 

 structure is observable. 



The demonstration of the presence of water in the entire 

 mass of the glacier, at all depths, is the most important of all 

 the facts obtained during my residence last year on the glacier 

 of the Aar ; and I am so much the more interested in bring- 

 ing this clearly out, because it is upon the absence of water 

 at great depths, that many authors, and especially Mr Hop- 

 kins, in his essay entitled Theoretical Investigations of the 

 Motion of Glaciers, found, in a great measure, their reasoning 

 against the glacial theory. Without pretending that all the 

 difliculties can be removed by the discovery of this single fact, 

 it will at least be conceded that it has enabled us to advance 

 a step farther towards the solution of the problem. 



I now come to a no less important fact, that of the lamellar 

 structure of glaciers. This remarkable phenomenon, which Pro- 

 fessor Forbes has described extremely well in the Edinburgh 

 New Philosophical Journal,* but of which he has erroneously 

 claimed the discovery, and has assigned to it a generality 

 that the facts he has himself observed did not at all justify, 

 was for the first time observed in 1838 by Professor Guyotof 

 Neuchatel, on the glacier of the Gries, at a height of 7500 feet; 

 and that naturalist made it the subject of a highly inte- 

 resting communication to the Geological Society of France, 



* For Januiu7 1842, vol. xxxii. p. 84, 



VOL. XXXIII. NO. LXYI. OCTOBER 1842. B 



