126 MI^ED CASKS, 



XV. 



Lelitr to the E^tor from Mr, William Henry, in reply td 

 Mr, Gough. 



Manchejler, September 13, 1804. 

 SIR, 



Previous re- iSloTHING was farther from my intention, when I com- 

 municated to you the " Illuftrations of Mr, Dalton's Theory 

 of Mixed Gafes," than to enter into controverfy refpeding a 

 do6lrine, to the defence of which I may naturally be fuppofed 

 to be much lefs competent than its author. Yet it is certainly 

 required of me, both by the refpe6lful attention due to your 

 correfpondent Mr. Gough, and to others of your readers, 

 either to explain and fupport, or to relinquifli, if erroneous, 

 the opinions refpefting which I have publicly exprefled a coin- 

 cidence with Mr. Dalton. The laft alternative I do not, at 

 prefent, feel difpofed to adopt, becaufe I am far from being 

 convinced by Mr.G.'s reafoning; and in the explanation, which 

 I am about to offer, I Ihall confine myfelf to thofe proofs of 

 the new theory of mixed gafes, which are furniflied by my 

 own experiments; leaving to Mr, Dalton the more important 

 office of eflablifliing its fundamental evidences. 

 The quantity of It is by no means clear to me, whether or not Mr. Gough 

 gas abforbed denies the principle, ** that the relation between gafes and 



being as the • i i i • i »jt. rr^ i • 



preflure, the laft water IS altogether a mechanical one. * To me this appears 

 is taken to be as legitimate an inference, as can poffibly be deduced in phy- 

 * fics; for the quantity of every gas, abforbed by water, follows 



exactly the ratio of the preiTure: And, fince it is a rule in phi- 

 lofophizing, that efre6ls of the fame kind, though differing in 

 degree, are produced by the fariie caufe, it is perfectly fafe to 

 conclude, that every, even the minutefl portion of any gas, 

 in a flate of abforption by water, is retained entirely by incum- 

 bent preflure. There is no occafion, therefore, to call in the 

 aid of the, law of chemical affinity, when a mechanical law 

 fully and fatisfaClorily explains the appearances. And when 

 the effed ceafes, it is equally conformable to juft reafoning to 

 infer, that this happens, in every cafe, folely in confequence 



* Certain acid gafes, the muriatic for inftance, are obvioufly ex- 

 cluded. 



of 



