1844.] WRINKLES OF THE ICE GLACIER OF GRINDELWALD. 41 



convex surface, but that it is indented by furrows or wrinkles, 

 which would give a section like fig. 7, in a direction parallel 

 to the length of the glacier A B, fig. 6, the dots here indicating 

 the snow wreaths as before, and the broken lines approximating 

 to the direction of the frontal dip of the veined structure in 

 this part of the glacier. These periodical undulations (to use a 

 technical scientific term) are, beyond question, very important 

 in the theory of glaciers generally, and of the dirt bands in par- 

 ticular. Their existence will, probably, be thought to yield 

 some confirmation of the theory of semifluid motion of the ice, 



Fig. 7. 



even although their precise origin be still obscure. A homely 

 comparison, but a striking one, may be found in the wrinkles of 

 the horns of many animals ; and, though it may appear fanciful, 

 there is perhaps more than a vague analogy between the facts. 

 I hope, at some future time, to offer a better elucidation. 



After some stay at Chamouni, I proceeded, by easy journeys, 

 to Grindelwald, whose beautiful and easily accessible glaciers 

 I had not visited for many years. I there found an exact 

 confirmation of the views which I have published respecting 

 the origin and structure of glaciers. I found the forms, simple 

 and compound, of the ribboned structure, to be such as I have 

 described, including the gradual rise of what I have called the 

 " frontal dip," from a very low angle near the lower end of the 

 glacier up to 75 towards its origin, especially on the Glacier 

 of the Strahleck, above the Zasenberg, where it forms the Mer 

 de Glace of Grindelwald. The other principal affluent of that 

 icy sea, viz. the glacier descending from the Viescher horner, 

 exhibits the same wrinkles exactly as those which I have just 

 described upon the Glacier du Geant, perhaps even better 

 marked. As the lower glacier of Grindelwald furnished an 

 excellent example of all the modifications which I have elsewhere 



