DYNAMICAL GEOLOGY. 



of the Alps, and not before the upheaval, as Agassiz had 

 assumed. The particular distribution of the transported 

 blocks upon the slopes of the valleys, often in long lines, 

 affords, in Charpentier's opinion, clear proof that river-valleys 

 had already been eroded in the mountain-system before the 

 glaciers made their descent to the plain. Neither does he 

 agree with Agassiz that the Ice Age was the result of a 

 universal fall of temperature over the earth associated with 

 astronomical causes, but regards the climatic variations in the 

 Alps, and the advance and greater dimensions of the glaciers, 

 as local phenomena. 



Although Agassiz and Charpentier differed in their general 

 conclusions, both followed the true inductive method, and the 

 leading principles which they established by their study of the 

 Swiss glaciers have held their place in geological literature. 

 The moraines and appearances produced by them had been 

 treated by Agassiz with the fullest detail and the most brilliant 

 results. But between 1840 and 1845 tne glaciers themselves 

 were made the chief subject of his investigation. 



Provided with physical instruments and a boring apparatus, 

 he went in 1840 to the Grimsel Hospice; on the median 

 moraines of the Lower Aar Glacier he erected a primitive hut, 

 the "Hotel des Neuchatelois," which he occupied together 

 with his companions, E. Desor, C. Vogt, F. von Pourtales, 

 C. Nicolet, and H. de Coulon. Agassiz and Pourtales under- 

 took the meteorological observations and the investigations on 

 the inner structure and movement of the glaciers. Vogt 

 studied the microscopical fauna of the red snow, Nicolet the 

 flora of the neighbourhood, Desor and Coulon the glacier 

 appearances and the moraines. In the following years, Escher 

 von der Linth, the Scotsman J. D. Forbes, the artist Burck- 

 hardt, and others, took part for a time in the work on the Aar 

 glacier, and in the ascents of the Jungfrau, which were made 

 under the care of the guide Leuthold. 



The researches made from the hut were the first systematic 

 observations on the movement of ice in the different parts of a 

 glacier under the various diurnal and seasonal conditions, 

 and on the temperature of the ice at different seasons, while 

 the first facts regarding the thickness and internal structure of 

 the ice were secured by means of borings. 



While Agassiz and his band of enthusiastic workers were 

 busy in the high levels, the lower valleys at the north and 



