^46> ATTRACTION OF WATER BY AIR. 



A<mofpheiical circumftances ; confequenlly (he denfity of ihe former exceeds 

 dirafnnple gas. ^i^^j ^f ^i^g h[{er. fuppufing their elaftic forces to be equal. 

 On this account founds will move, in all cafes, with lef:^ ce- 

 lerity in oxigen than they do in azote. If tb.en our atmofphere 

 confified of two independent raaflfes of thefe fluids, mutually 

 pervading each other, every momentary report would have 

 been double to fenfe, at a fufticient diflance from the feat of 

 found; becaufe fuch a report would arrive at the ear more ex- 

 peditioufly through the medium of the azote, than it would 

 through that of the oxigen. But founds of the (liorteft duration 

 are not repeated at the grealefl, diftances; confyquenlly the 

 air is homogeneous, becaufe it is the vehicle of found. 



If the preceding arguments be juft, the homogeneity of at- 

 inofpherical air cannot be controverted ; becaufe the conclu- 

 iions v^hich refult from the contrary hypotiiefis are repugnant 

 to common experience. We conie in the next place to the 

 fpecific nature of this gas; but this is a difficult enquiry in the 

 prefent unfettled (late of chemiftry, when the phenomena of 

 galvanifm are daily bringing new truths to light, and threaten 

 to fubvert the prevailing theory. Conje6lures, however, vvill 

 r.aturally fpring up in the midft of uncertainty ; and as a di- 

 verfity of fentiaient has its ufe in times of fcientific anarchy, 

 I will venture to propofe the following hypothetical queflions 

 relative to the conRitution of common air. Is not this fluid p 

 chemical compound, having the gas called azote for its bafisj 

 to which the pofilive energy of the galvanic pile is united, to- 

 gether with water, but in a manner which difiinguiflies this 

 coinpound from the gafeous oxide of azote? May not a gas^ 

 thus conllituted, oxidate other fubftances through the interpo- 

 iition of the water, which it holds in folution by the hygro- 

 metrical attradlion ? Though the aqueous part of the atmof- 

 phere cannot of itfelf decompound common air; may not it 

 perform the office of an intermediate agent, when affified by 

 the body to be oxidated, and in tiiis manner deprive the azote 

 of the galvanic energy, more or lefs perfeftly, according to 

 circumflancc's ? Will not the aqueous vapour unite with the 

 matter feparated from the air, and produce oxigen gas, which 

 will enter into compofition with the third lubftance, and com- 

 plete the bufinefs of oxidation ? The hints fuggefted in the 

 preceding queries, would have been by no means admiffible 

 ♦ in a time of more perfed uniforn;iity in the fenUments of phi- 



lofophers; 



