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selves : 3. That frozen water does not evaporate at all, 

 if it be kept from the agitation of the air : 4. That the 

 diminution observed in ice exposed to the open air, is 

 not from any evaporation, but is the effect of a fine 

 rasping by the wind, rubbing against it and carrying off 

 its finer particles. And what is thus detached from, ice 

 is only a very fine dust, not more different from ice 

 than the durt of free-stone, cut from the stoue 

 itself. 



This dust carried by the wind produces intense cold. 

 Nor is it always invisible. The air near Hudson's Bay 

 is often filled with particles of ice, fine as hairs, and 

 sharp as needles ; which, if they strike against the bauds 

 or face, pierce the skin and occasion painful blisters. 



The natural state of this globe seems to be in an in- 

 termediate degree between heat and cold. And this 

 natural warmth of the earth is what secures many springs 

 from being frozen : the frost in England seldom pene- 

 trating tiie earth, more than fourteen inches below the 

 surface. Even in Sweden bubbling springs do not freeze 

 at all, while the standing waters freeze three ells deep* 



In the lakes of Sweden the ice often cracks, with a 

 rupture nine or ten feet deep, and many leagues long, 

 and with a noise like cannon. Hereby the fishes get air, 

 so that few of them are destroyed. In Moscow the 

 earth is often cleft by the frost, a foot broad and many 

 yards long. In the mountains of Switzerland there are 

 vast masses of ice, which have lain there for many cen- 

 turies. At certain times these crack, and by those 

 cracks one may guess at the immense thickness of them ; 

 some of the cracks being three or four hundred ells 

 deep, though none of them have ever gone through the 

 whole thickness of the Ice. 



We need not then be surprised at the effects of severe 

 frost on trees and other vegetables. How these are 

 hurt in hard winters is easily understood, if we consider 

 that water, when frozen, takes up more space than it did 

 before: that all trees, especially those that shed their 

 leaves, drink in a large quantity of moisture in summer,. 



