ON POTASSIUM, SOBItJM, AND OXIMURIATIC ACID- 



133 



und trust-worthy table of the speciiic gravity of muriatic 

 and oximuriatic arid gasses before the value of the experi- 

 ment can be duly appreciated; and it should be farther 

 ascertained wlmt proportionate condensation of volume is 

 produccv5 upon muriatic acid gas by admittin*^ to it ,\ of 

 its weiglit of water. It is curious to observe, that your cor- 

 respondent was fully persuaded, and proi. ably continues to 

 be, ofthe** incontrovertible argument 'the above experiments 

 afford to Mr. Davy*s opinions in regard to oximuriatic acid, 

 though he did not know at the time he wrote, whether the 

 •pecific gravity of muriatic acid was 1*4, or 1*9, but took it 

 at V7 ; and he now adopts I '258; and of the specific gra- 

 vity of oximuriatic acid he makes no mention whatever; 

 neither ofthe condensation or contraction of volume which 

 a very small portion of water produces on muriatic acid 

 gas; yet it is impossible to ascertain the bearing of the ex- 

 periments, till these three data are all of them pretty accu- 

 rately investigated. If your correspondent wish to institute 

 his calculus anew, I shall give him all the information I can 

 respecting oximuriatic acid: its specific gravity by my own 

 experience is 2*34; by Mr. Davy's, 2*45; by Thenard and 

 Gay-Lussac*s, 2*47; and by Dr. Thomson's, (in a letter to 

 me) 2'71. If the last estimate should be true, he will find, 

 that, adopting Mr. Davy's notions and estimate of muriatic 

 acid, there should arise nearly '-2^ measures of muriatic acid 

 gas from a mixture of 1 of oximuriatic acid and 1 of liidrogen. 



There is one opinion on which we all concur; that it is Specific gra- 



verv desirable the specific gravities ofthe various gasses '^"y "^ 5»sses 



, -^ , , , .;.,."• -. . ,, ^ . •till a desidera- 



should be ascertamed withm narrower limits, r rom what is turn of im- 



stated above, it appears, we have a range from 1*3 to pg portance. 

 for muriatic, and from 2*3 to 2*7 for oximuriatic acid. v 



Would it not be a proper object for the Royal Society to 

 depute a committee of its members to undertake the inves- 

 tigation? As long as it is left to individuals, each one "^ g 

 finds a result differing from that of another; and one autho- ^ 



rity is deemed as good as another ; so that it will, if no such 

 step is taken, be a long time before a general agreement 

 respecting these points is likely to be obtained. 



Manchester, 1 remain. Yours, 



Matfihe nth, 181U JOHN DALTON. 



VIII. 



