410 On the Tlieori/ of Mixed Gases. 



letter appear to contain all that is necessary to 

 virtdicate the mathematical part of my theory ; 

 consequently it is time to dismiss the subjectj 

 and to take a review of such of his objections 

 Hs are intei>d^d to weaken the force of the 

 coriclusiom, whick I have deduced from re- 

 pirted fact^ and ^my own experience. To 

 begin then with hi's objections to the argu* 

 ments, which • ^fr. Schmidt's experiments 

 supply me with, it will be adviseable to give 

 th-em in the woiids of Mr. Dalton's letter. — 

 ** Another argiimeht against me is derived 

 *^ from Schm id t*s experiments on the expansion 

 *' of dry and moist air: from which you justly 

 "'infer, (with the exception of a small error in 

 " taking Schmidt's number for moist air for 60* 

 *' instead of 59°) that if my theory be right he 

 "-must have made his experiments on air of 

 *' 15 or 16 inches pressure, and some of them 

 ** on air from 8 to 5 inches pressure. Now I 

 " have no hesitation in resting the merits of the 

 *> theory upon this inference ; lif a theory wiii 

 ** in all cases tell how a man has made his ex- 

 ^*-periments, I take it to be a tolerably goadT 

 wfbnc. The volume of Gren's Journal, con- 

 '** taining Schmidt's apparatus, is not in Maib- 

 ** Chester ; but I hope soon to learn th-e fact. 

 " In the meantime I have the authority of 

 ^' Col. Roi, de Sau68Upe> and yout own to<:or- 



