152 GLACIER MOVEMENT. 



as the fronts of those at Spitzbergen generally 

 are, and says, " The lower parts of the field 

 being nearer the tempered mass of the ocean, 

 are not so cold as those which project into the 

 atmosphere ; and consequently the air which 

 ascends becoming chilled in sweeping over the 

 eminences, there deposits its moisture, forming 

 an icy coat. But this continued incrustation, 

 in the lapse of ages, produces a vast accumu- 

 lation, till the shapeless mass is at length pre- 

 cipitated by its own weight." But, rational as 

 this theory seems, and correct to a certain ex- 

 tent, it does not appear sufficient to compensate 

 for the loss which we had daily opportunities 

 of witnessing during our stay at Spitzbergen, 

 and we must, I think, look to the thawing snow 

 mainly for the sustenance of the glacier. 



With regard to the glaciers of Switzerland, 

 the most remarkable phenomenon seems to be the 

 progressive motion of the entire mass toward 

 the plain beneath ; a fact which, extraordinary 

 as it must appear, has been satisfactorily ascer- 

 tained by M. Hugi and M. Agassiz. The former, 

 in 1827, had occasion to construct a hut on the 

 glacier of the Finster Aar ; in 1830 he visited the 

 spot, and found this chamber several hundred feet 

 below its original position. In 1836 it was found 

 two thousand two hundred feet from the foot of 



