450 
GLACIERS. 
The change of the Arctic snows into n6ve or firn 
might be the suhj ect of interesting examination. Even 
the surface drifts of our winter ice-floes underwent this 
granular transformation rapidly. After tossing about 
as a dry and almost impalpable powder during the 
long Polar winter, the returning sun, with its alterna- 
tions of thaw and congelation, developed a grain-like 
or almost headed structure. I have seen these crys- 
talline pellets as large as a cherry-stone, diminishing 
down to the size of shot or mustard-seed. 
The Polar glacier, as may he seen clearly when it 
has taken the berg form, is commonly coated over 
with this modified snow, and its valleys and minor 
depressions are often filled with it by drift-action. I 
have noted by sections strata of fifteen and twenty 
feet, whose composition was entirely analogous to the 
firn of the Alps. It may have been by observing por- 
tions of the berg like this, that Professor Forbes was 
led to the assertion that the iceberg is composed not 
of true ice, hut of neve. 
That the Polar glaciers obey the same law of move- 
ment as their Alpine brethren, I have seen no reason 
to doubt. The advance of the glacial faces at Jacobs’ 
Harbor, of which Mr. Olrik informed me, is the only 
direct fact which I can add to those already noted on 
this subject. But the very circumstance of their off- 
casts, the bergs, being so numerous, seems to indicate 
a continuously protruding influence. It may be that 
in the more southern settlements of Greenland this 
advance is limited by atmospheric causes ; hut I am 
strongly inclined to believe that in those further north, 
the debacle or berg disgorgement is the most powerful 
countervailing agent. 
It would he presumptuous, with my very meagre 
