|08 ON ATMOSPHERIC PHENOMENA. 



of the air in its aqueous combination; and that which falls 

 with a sinking of the barometer and a rise of the thermo- 

 meter is a ram of decomposition of the air with respect to 

 that combination. 

 The barometer I cannot easily conceive, how people continue to ascribe 

 increased elas- to tne we '» nt °f *h e an ' tnat pressure, which this fluid ex- 

 ficity oftheair, erts on the mercury in the barometer; while we see it almost 

 ■wei^hT" 1 ' * a ^ wa y s increases this pressure, when it loses part of its mat- 

 ter, or gravitating power; and diminish it when the air is 

 at a. maximum of aqueous saturation, or just before rain; 

 and when the bulb manometer, or true aerostatic balance, 

 indicates the ultimate degree of density in the air ; and that 

 all other phenomena," both those that occur in nature, and 

 those that present themselves in experiments with the mer- 

 curial pump, prove to a demonstration, that the air presses 

 chiefly by virtue of its elastic power, which is increased by 

 condensation, and by the addition of caloric, the matter 

 remaining the same in a closed space; and diminished by 

 rarefaction, and the subtraction of caloric, the matter re- 

 maining equally the same, and in the same space; but 

 which is neither increased nor diminished in the open air, 

 but by the association, more or less elastic, more or less so- 

 lid, of water with air. 

 Experiments This proves how little applicable to atmospheric pheno- 



™ confilied aif m ena are the results we obtain under our glasses, in which 



not applicable , . . 



to meteorology, the air is deprived of its free motion, and where this fluid 

 is withdrawn from the effects of rarefaction and condensa- 

 tion produced bj sidereal influences ; which effects, added 

 to the more or less permanent or solid gassification of water, 

 and the transformation of light and of heat into electric 

 fluid, give rise to all meteonc phenomena, and occasion by 

 their frequent variations the great variableness of the state 

 of the atmosphere. 

 Formation of The first portion of water decomposed into gas, while it 

 clouds, changes the composition of the air, and increases the den- 



sity of this fluid at the point where this decomposition takes 

 place, determines the formation of other clouds, which de- 

 pose also electric fluid, and are in part decomposed, and so 

 Ch\r»ed with on. The electric fl id, that does not combine to gassify 

 electricity. t j ie principles of water, charges- these clouds by strata of 



opposite 



