IJH Nezu Theory of the Conjt'iinthn of mixed Gafes ehicuIalecL 



tiioir doArine of ftatics. Till then I mufl; take the negative of 

 the pmpofilionj and conclude that elafiic fluids of the greateft 

 and leaft fpecific gravity imaginable, on the fuppofition [ hold, 

 will alike take the lowelt and the higliell ftations, regardlefs 

 of each other; or, in other words, they will arrange themfelves 

 in the fame order as if thrown into a complete vacuum. The 

 great difficulty refpecting the uniform ditiufion of the gafes 

 being removed, I think on my hypothefis the other phaeno- 

 mcna can require no explanation to anv perfon convcrfant iii 

 pneumatics, I will take one inftance : it may be alked, How 

 floes fulphuret of potafli abllraft oxygenous gas out of any 

 mixture; lime water, carbonic acid gas, &c. &c. ? The an- 

 fwer is obvious ; Exactly in the fame way as if the gas in 

 queftion was the only one in ihc veflcl, and the operation 

 going on in a clofe velfel. 



III. Gafes held together hy chemical Affinity ahjurd. 



On this head it will be proper to premife certain fads: 



ift, When two gafes of different fpecific gravity, fnch as 

 oxyaenous and hydrogenous, are put into the fame veffel and 

 agitated ; then, after Handing fome time, they dill continue 

 uniformly mixed. 



3. They occupy the fame fpace before and after mixture; 

 that is, 07ie meafure of each put together occupy t--xo mea- 

 fures, the temperature and preffure being the fame. Mr, 

 Davy fccms to think this principle not ftriftly true in regard 

 to a mixture of azotic and oxygenous gas ; but the deviation 

 frorii it, if any, is extremely fmall. 



3. The compound is fubjecl to the fame laws of rarefadion 

 and condenfation as the fimples. 



There are but three fuppofitions we can make eficntially 

 cJifferent rcfpccling the mutual action of heterogeneous par- 

 ticles of gas. I ft^When two gafes are mixed, their particle? 

 may reciprocallv repel one another, juft as they a6l on their 

 own kind in an unmixed (late : 2d, They may be neutral, or 

 have neither attraftion nor repulfion for each other : 3d, They 

 may have a chemical affinity or attradmi for eacli other. 

 The advocates for tlie chemical adhefion of gafes will agree 

 with me in cxpU^ding the frji, bccaufc, where nothing but 

 repulfion is manifeU, we can afcribc no effcft to attra6tion : 

 llie fecond, which is the one I adopt, is obvioufly inconfiUcnt 

 v.-ith their hvpoihefis : and as for the third, I can conceive 

 no other explanation than the following: ifl, Two or more 

 lictcroo;eneous particles may unite, and become a new centre 

 tor the caloric to adhere to; but in this cafe the gafes are no 



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