IQB ON THE NATURE OF OXIMUMATIC ACll>. 



Want of ac- Mr. Murray is of opinion, that tlie want of action ber . 



Han between t^^f^Q charcoal and oxirnuriatic gas fs an; anomaly, in Mr, 



charcoal and „ , , , • , , ; . , , , , , • 



oxirnuriatic l>avy s theory, which does not exist ui the old hypothesis. 



K^* To account for this fact he has recourse to a predisposio'^ 



affinity, and to the supposition, that water" is necessary to 

 the existence of the muriatic and carbonic a(.'ids in a o-aseous 

 state. And he remarks, that, as water was not present 

 when the experiment was made on the ignition of charcoal 

 by Voltaic electricity in oxirnuriatic gas, it followed, that 

 no alteration could be produced, that no oxiiuuriatic gas 

 could be decomposed, or any muriatic or carbonic gas 

 formed. This reasoning would have been less unobjection- 

 able, were it less hypothetical. Mr. Murray doesruot 

 prove, that the muriatic and carbonic passes contain water; 

 he supposes that they do. The only fact advanced in fa- 

 Water sup- vour of this constitution regards carbonic acid gas. It i^ 



posed to be ne- ^,^11 known, that the native carbonate of barytes diflierg 



cessarv to car- . , . . . 



bonic acid gas from the artificial in being indecomposable by heat alone; 



from Its assist- ^j^ J that this difference ceases, when the action of fire is 

 ing the de- 



compoiition assisted by steam or aqueous vapour. Mr. Murray sup- 



of native c^r- p^jges, that steam produces the decomposition by entering 



rytes; into union with the carbonic acid, and forming carbonic 



acid gas. I should conceive, that he would not have 



adopted this supposition, were he acquainted with Mr. 



but this it does Berthollet's observations on barytes. From this gentle- 



the^eaatri'ni^ man's experiments it appears, that the water does not com- 



a fusible hi- bine with the acid, but with the earth, which it converts 



'^*^' into a fusible hidrate, and thus liberates the carbonic acid, 



wliich immediately escapes in the gaseous state*. 



Argument of Thougb Mr. Murray has not endeavoured to demonstrate 



Mr. Murray ^]-jg presence of water in muriatic acid gan, he has at* 

 for the exist , , , , . i i i • i -.tt- 



lence of water tempted to show, that this probably is the case. When 



in n.uridtic jji^. y^'id gas has been exposed to the action of substances 



strongly attracting water, Mr. Murray observes, " it can 



only bir affirmed, that a portion, of water is abstracted frwn 



it, not that the whole of it has been withdrawn. As the 



Water is removed from the acid gas, the aCiuity.-by which 



the remaining quantity is retained must prodigiously ipr 



• 'Memoires d' Arcuneil, torn. li, p, 17. 



crease 



