Researches on Existing Glaciers. 267 



from one wall to the other, and can be traced for spaces of 

 hundreds of yards, always preserving a perfect parallelism. 

 They are to be seen descending in this manner into the mass 

 of the glacier, as far as the eye can reach into the crevasses, 

 sometimes to a depth of ten and fifteen metres (yards). Their 

 direction is generally parallel to the axis of the glacier ; but they 

 are not always rectilinear ; for I have seen on the glacier of 

 Aletsch and elsewhere, contortions and dislocations of diffe- 

 rent kinds, and M. Guyot remarked the same thing in the 

 Gries glacier. Although the observations made at the be- 

 ginning of our residence on the glacier of the Aar induced me 

 to believe that this lamellar structure extended to a large por- 

 tion of the mass of the glacier, I was nevertheless desirous to 

 assure myself, in a direct manner, that it did so, and with this 

 view, I descended into one of those hollows or pits in the 

 glacier, where most of the streams which trace a serpentine 

 course on its surface are swallowed up. I was thus enabled 

 to follow the blue and white bands as far as the accumulation 

 of water at the bottom of the hole permitted me to descend, 

 that is to say) to a depth of 120 feet. 



The following is a short account of the descent, which my 

 travelling companions afterwards denominated my descente 

 aux infers : — 



It was towards the termination of our residence on the gla- 

 cier ; we had finished our boring, and were preparing to depart, 

 when, while discussing, according to custom, the phenomena 

 we had observed, one of the party remarked that it would per- 

 haps be easy to descend without danger into some one of the 

 pits of the glacier, and that perhaps some unexpected appear- 

 ances might thus be observed. All were of this opinion, and 

 without delay we commenced looking for a pit suited to the 

 purpose. These pits, as I have remarked in my Etudes sur 

 les Glaciers, are probably old crevasses, which a small stream 

 of water has prevented from being completely closed ; so that 

 instead of being of an elongated form, they are, on the con- 

 trary, for the most part circular, and the rivulet, far from con- 

 tracting them, tends to enlarge them more and more, espe*- 

 cially when it is considerable. We found at some distance 



