AND ON SOME SUBJECTS OF CHEMICAL THEORY. 315 



per analogy is that of the oxymuriatic with the sulphurous 

 acid, and the muriatic with the sulphuric ; and under this point 

 of view there is no anomaly, but strict conformity. And thus 

 also is accounted for, what is at variance with the hypothesis 

 of Gay Lussac, the total want of analogy between chlorine and 

 sulphur, which he classes together, except in the single cir- 

 cumstance of acidity being communicated to both by hydro- 

 gen ; while there exists a close analogy between sulphurous 

 acid and oxymuriatic acid, in their most essential properties, — 

 their gaseous form, their specific gravity, their suffocating 

 odour, their power of destroying vegetable colours, their solu- 

 bility in water ; their remaining combined with it in congela- 

 tion ; their acidity, their combining weights, and their being 

 attracted to the positive pole of the voltaic series ; and any de- 

 viation from this analogy evidently arises from the excess of 

 oxyen in oxymuriatic acid*. 



It is obvious, that it would be in vain to seek for the disco- 

 very of real muriatic acid in its insulated form. It exists no 

 more than real sulphuric or real nitric acid. The oxygen and 

 sulphur, or oxygen and nitrogen in union with a salifiable base 

 in the sulphates and nitrates, may not be in direct combina- 



K r 2 tion, 



* It is curious with regard to the most important of these analogies, that of 

 the equivalent or combining weights, that oxymuriatic acid stands next to sul- 

 phurous acid ; the former in Dr Wollaston's scale being 44, while the latter 

 will be found to be 40. The acidity of oxymuriatic acid is fully established by 

 the most unequivocal acid property, that of combining with alkalis, and forming 

 neutral compounds. The saline nature of these compounds had been shewn by 

 Berthollet; that with lime has been demonstrated by Mr Dalton, who also 

 pointed out the probability from the results, by double decomposition, that the 

 acid combines in a similar manner with other salifiable bases ; and the existence 

 o£ these compounds has been established by Mr Wilson. 



