Acids, Alkalis, and their Compounds. 93 



no evidence, therefore, of tlie existence of any such compound as 

 that of real sulphuric acid. 



But there is another case which does not admit of the same 

 explanation, and in which the relation of 1 of sulphur to 1| of 

 oxygen seems to be demonstrated. It is that of the actiou of sul- 

 phurous acid on salifiable bases. Here, as there is no abstrac- 

 tion of oxygen in the formation of water, while there is the ad- 

 dition of the oxygen of the base, the proportion in the combina- 

 tion is that of H to 1 of sulphur. This will be apparent from 

 the same example of oxide of lead. 20 of sulphurous acid com- 

 posed of 10 of sulphur and 10 of oxygen combine with 69'6 of 

 oxide of lead, composed of 64*6 of lead and 5 of oxvgen: sup- 

 posing a simultaneous combination to be established, the propor- 

 tions will be 10 of sulphur, 15 of oxvgen, and 64*6 of lead; and 

 supposing the two latter to observe a relation to sulphur, the 

 proportion is thnt of 100 to 150 of ox\gen. 



It might be maintained that no change of composition in the 

 two binary comj)ounds, the sulphurous acid and oxide of lead, 

 takes place, but that they merely unite ; or, at least, that while 

 the sulphur and lead display their peculiar relation to each other, 

 each of them retains its relation to oxygen. But this is incon- 

 sistent with the genera! view which has been given of the state of 

 a neutral compound, and can scarcely be supposed to exist with 

 regard to one case, when the reverse is maintained with regard 

 to others. 



At the same time, the relation of 100 of sulphur to 200 of 

 oxygen is fullv established in common sulphuric acid. Whether 

 it is necessary to admit that of 100 to 50, except on the atomic 

 hypothesis, is not apparent, but it is not improbable. 



The same view may be Applied to the illustration of the acids 

 of which carbon is the radical. 1 have renwirked in the preceding 

 paper, that the vegetable acids are to be regarded, not according 

 to the doctrine of Lavoisier, as composed of a compound radical 

 of carbon and hydrogen acidified by oxvgen, but as compounds of 

 a simple base, carbon, acidified by oxvgen and hydrogen. On 

 this principle the question occurs. What is their precise composi- 

 tion ? The proportions assigned by the analyses hitherto given 

 appear at variance with every principle, and can be brought under 

 no law, nor any analogy whatever; nor has this been attempted. 

 Part of this may arise from the didicultics of the analysis, but 

 more of it perhaps is to be ascribe<i to the composition not hav- 

 ing been considererl under the just point of view ; — in more re- 

 cent investigations, particularly in which oidy accurate experi- 

 mental results can be expected, to the idea having been enter- 

 tained that they contain a portion of combined water in their in- 

 sulated state, which they yield when combined with a base, and 



that 



