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thefe qualities ? Or has hydrogenous gas any fhare in it ? Warmth, 

 ading in concurrence with moifture, has unqueftionably vital in- 

 fluence on the vegetable fyftem ; but, even in our open winters, 

 cold days frequently occur, the folar heat is naturally weak, and 

 moon-light does not appear to poffefs any influence deferving 

 notice in this cafe. And as to the part which the foil has in the 

 procefs, it may be obferved, that the verdure is not confined to 

 warm and rich grounds, but extends proportionably to every foil 

 where herbage exifts. But it may be further remarked, that in 

 fome of the colder weather of our verdant winters, the nights, 

 particularly in their beginning, are often fenfibly warmer than the 

 days. Now, to touch on the borders of hypothefis, we fliall afk, 

 Is the fuperior temperature of thofe nights owing to the efcape of 

 caloric, during the tranfition of water from its mixture with air 

 into a more aggregate ftate ? Taking this queftion in the afiirma- 

 tive, is it not conceivable that, in the pafl"age, fome of the water 

 might be decompofed, and its hydrogene, coalefcing with the free 

 caloric, become hydrogenous gas ? However this may be, one 

 thing appears certain, that the atmofphere is fometimes fo highly 

 charged with inflammable gas, that the eledric fluid, in regaining 

 its equilibrium, fets on fire the gas, and occafions igneous meteors, • 

 even very near the furface of the earth. (See Note i,) 



The 



