Z^6 Ohferz'atians on the Freezing of Heater, ^e, 



fi.ll ia cafes of iiiflaniniation of the eyes ? why it occafions 

 colic, griping pains, and other afl'eiilions, when drunk cold ? 

 But, without enlarging further on this fubjeft, I fliall here 

 nxention a remarkable eft'eft of the wife difpcnfations of Na- 

 ture. As fnow water contains oxygen united with little ca- 

 loric, it thereby pofleifes a (Ironger tendency to communicate 

 its oxygen to bodies fufceptible of oxygenation. No fubftance 

 in nature deprives water of its oxygen with more avidity than 

 fertile earth. Snow water mixed with vegetable mould, and 

 expofed to the folar light, improves the mould in a fliort 

 time. Almoft as foon as a lively fiOi placed in a glafs of 

 water containing oxygen makes the fuperfluous oxygen dif- 

 appear,and fills the water with carbonic acid gas in its room, 

 is the oxygen taken up by the earth aflifted by the influence 

 of the light. Pure earths do not exhauft fnow water of its 

 oxygen ; nor do they attraft the oxvgen of the atmofphere, 

 as afl'erted by Von Humboldt. 



I have long been convinced of the contrary, from various 

 experiments. Tt appears, in particular, that carbon is the 

 principle whofe ftrong affinity for oxygen produces fo many 

 important phasnomena, and which nature continually em- 

 ploys in the compofitiou and decompofition of organic bo- 

 dies : it is carbon alfo which in this Cafe deprives water of 

 its oxygen, and confequently frees it from what renders it 

 prejudicial to health, and unfit for the purpofes of life. 



That which is prejudicial to us is improved by the ground, 

 and at the fame time gives power and adlivity to the mould. 



When the inow covers the earth, it tends to keep it warm : 

 the fnow, as a body which cannot conduit caloric in a very 

 fmall degree, prevents, by its interpofition, the cold air from 

 taking the caloric from the earth. But this does not appear 

 to be the only caule of its fertilizing power. The fnow melt- 

 ing and penetrating into the foftened earth commmiicates to 

 it oxygen, promotes by thefe means the germination of feeds: 

 the young plant grows with more vigour, becaufe the carbon 

 of the fertile earth combining with the oxygen is converted 

 into carbonic acid, and thereby acquires more iblubility ; while 

 the water, by its Simulating property, contributes to excite 

 that a6livity which had been rendered dormant in the roots 

 by the cold. 



This fertilizing power of fnow, which was before afcribed 

 to nitrous particles, but the prefence of which was never 

 proved, feems thus, according to the idea of Ingenhoufz, Haf- 

 feufraiz, and other naturalills, to be explaiueB in a more fa- 

 tisf'tAory manner. 



. I lliall now conclude this fliort eflay by expreffing a hope 

 • ' that 



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