AND ON SOME SUBJECTS OF CHEMICAL THEORY. 321 



proportion of oxygen and hydrogen, than nitric acid. And 

 some of the acids lately described, of which phosphorus is 

 the base, may arise from variations of proportions of this 

 kind. 



The view which I have now illustrated, I must add, is not to 

 be regarded as mere speculation. The evidence in support of 

 it, is just as conclusive as that from which the opposite opinion 

 is inferred. The obtaining water from a compound is no ne- 

 cessary proof that water pre-existed in it ; and conversely, the 

 causing water to enter into combination in a compound, is no 

 necessary proof that it remains in the state of water in the 

 product. In many cases we draw the reverse conclusions, con- 

 sidering water as being formed where it is obtained, and as de- 

 composed where it is communicated. And in the case of its re- 

 lation to acids, it will be found that there is no strict evidence 

 of its existing as water in combination with what is considered 

 as the real acid ; and of course the conclusion is equally open 

 to be drawn, that it exists in these combinations in the state 

 of its elements, and that when obtained, it is a product of a 

 change of composition. 



It is even more probable, a priori, that the ultimate elements 

 should act on each other where energetic affinities are evident- 

 ly exerted, than the immediate principles, and the relations of 

 these elements will determine the combinations, and the pro- 

 portions. And by admitting this view, we avoid the anomaly 

 which is presented in ascribing to the agency of water effects 

 so different from those to which it usually gives rise. In ge- 

 neral, water operates on bodies simply as a solvent, overcoming 

 cohesion in solids, diluting liquids, or absorbing gases, without 

 otherwise modifying their properties, or communicating to 

 them any important chemical powers. But in the particular 

 cases now referred to, it is supposed to produce the effects of 



Vol. VIII. P. II. Ss the 



