Dr Martens on the Glaciers of Spitzbergen. 163 



The height of the inferior glaciers above the sea depends on 

 two principal causes : the geographical position and elevation 

 of the mountains from whence they proceed. This is proved 

 by the following facts. In Norway, under 61° latitude, the 

 glaciers of Justedal rise to a height of 1850 metres, and de- 

 scend to 485 metres.* The inferior extremities of that of 

 Lodal and Nygaard are at 577 metres and 340 metres above 

 the sea -f In the same country, under latitude 67°, the glaciers 

 of Sala and Almjalos descend from a crest of the Sulitelma, 

 which rises to 1404 metres, and their lowest point is still from 

 778 and 974 metres above the North Sea.J We thus see 

 that the difference of 6° in latitude is more than compensated 

 by the greater elevation of the mountains of Justedal, com- 

 pared with that of Sulitelma. Even under the 70th parallel, 

 the glacier of Jcekulsfiord in Finmark does not descend to the 

 sea. In Iceland, 64° latitude, under the double influence of 

 one of the most rigorous climates in the same latitude and the 

 most elevated mountains, the glaciers reach the margin of the 

 ocean. But in no instance do they advance into it, for a free 

 space is always left, which admits of a passage between the 

 glacier and the waves. 



Distinction between the lower glaciers and the Mers de Glace 

 of Sicitzerland. — We cannot continue our comparison between 

 the glaciers of Spitzbergen and Switzerland without making, 

 at the outset, an important distinction. In Spitzbergen, or 

 at least in the north of that island, the line of perpetual snow 

 is at the margin of the sea ; consequently, the glaciers cannot 

 strictly he compared, except with that portion of the Swiss 

 glaciers which rises above the limit of continual snow. These 

 upper glaciers are very different from those which descend 

 into the inhabited valleys : Saussure, Charpentier, and above 

 all Hugi, have perfectly descrihed and distinguished them. 



* L. Von Bucli : Ueber die Grenzen des ewiger. Schnces in Norden. (Gil- 

 bert's Annalen der Pliysik, t. 41. p. 22. 1812.) 



t Nanmaim : Einige Bemerkungen auf Ausfluegen in die Norwegischen 

 Schneegefilde. - Leonhard'$ Taechenbuch, t. xvii., p. 167 and 18G. 182:i.) 



X Wahlenbexg : Bericht Kbet Meeeungen und Beobachtungcn zur Be- 

 etimmung der Ilohe und Temperatux del Lapplandischen Alpen unter dem 

 f>7 on. Breitegrad, iibersetzt von Haussmann. 1812. 5 1 7 et 29. 



