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Arctic Explorations. 241 



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ties. In tlie month of Maj, the thermometer, in the mean time, 

 never having risen in the interval to within many degrees of the 

 freezing point, I saw the same ice-table coniplctelj bent down, its 

 centre depressed five feet, until arrested in its descent by a new 

 support.'' These facts are referred to as proving a yielding na- 



ture m ice. 



AaZ/'-compacted. The 



bergs are described as not of the nature of the nev^ or consoli- 

 dated snow, as Prof Forbes suggests, but as true ice, ^' having 

 the fracture lustre, and other external characters of a nearlj ho- 

 mogeneous growth, although they may be opaque and vesicular." 

 He remarks that the berg is the foot of the glacier that quietly 

 detaches itself while it lies stretching itself out in the sea, and 

 not an avalanche that has fallen from the land. 



On the disappearance of the ice-fields, we cite the following 

 statements as bearing^ on the Question o;"* 



ice in Lake Champlain : 



disapp 



"It was interesting to observe the compensations by which Nature got 

 rid of this vast accumulation. The simple effects of solar heat, wliether 

 from the atmosphere above or the heated currents below, do not satisfac- 

 torily explain the dissolution of this ice. Changes in its mechanical 

 structure evidently took place, preparing the way for the subsequent ac- 

 tions of thaw. My attention was first called to this fact by hearing, 

 through my friend, Lieutenant Brown, that the observatory of Sir Jumes 

 Ross at Leopold Island w^as moist and saggy, while the outside ice re- 



mained dry and firm. In the month of May, while our m^'an tempera- 

 ture was still below the freezing point, I noticed, during my walks over 

 the ice, that certain surface floes, which had been during the winter 



1 hard and fresh, ])egan to yield under me as I walked, and gave a deci- 



r dedly brackish taste to the palate. The ice, 



tenacity and resistance. Our coal, which had been thrown out loosely 



too, in many cases lost its 



on it, so depressed the little area around it, as to be surrounded by water; 

 and some of the larger hummocks, whuse colossal blocks had attracted 

 my attention during the winter, were now wet and marshy to approach. 

 Upon excavating blocks of ice with the saw and pickaxe, it was found, in 

 many cases, to have lost its well-condensed character. It was divided by- 

 vertical lines into prisms, which stood prominently out, and ran continu- 

 ously from the watery to the atmospheric surface, with an arrangement 



almost basaltic* 



" Struck by this circumstance, T was led to test the ice of different lo- 

 calities by both the Marcet's bottle and the nitrate of silver, and discov- 

 ered that the floes, which had formed in midwinter at temperatures below 

 -30, were still fresh and pure, while the floes of slower growth, or of the 

 early and late portions of the season, were distinctly saline. Indeed, ice 

 which only two months before I had eaten with pleasure, was now so salt 

 that the very snow which covered it was no longer drinkable. 



* " I am happy to find since my return, that this basaltic arrangement of the ice 

 nas been noticed by Sir John Richardson." 



SECOjyo SERIES, VOL. XXIV, NO. 71. — SEPT., 1857. 



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