282 Dr. Murray on the Chemical Constitution of [Oct. 



chemical compounds is brought forward, different from what had 

 hitherto been proposed, it is incumbent to show that it is con- 

 sistent with the operation of this law ; and if just, this may 

 display relations not before observed, and may obviate objections 

 which have arisen from a different view. It is from these con- 

 siderations that I submit the following observations on the 

 application of the law of definite proportions to the theory which 

 I have proposed of the chemical constitution of the acids, alkalies, 

 and their compounds. It necessarily leads to considerable 

 modifications of these applications ; and the conclusions which 

 these afford, if I am not deceived, afford proofs of the truth of 

 the opinion I have advanced, and lay open some new views. 

 The subject is at the same time so extensive as to have relations 

 to nearly all the details of chemistry. 



In the preceding paper I remarked, that the relations in the 

 proportions of oxygen and hydrogen forming the supposed 

 portion of combined water in the acids, will probably be those 

 of one or both of these elements directly to the radical. It 

 remained to be determined how far this is just. 



Sulphur affords the best example for illustration, as its combi- 

 nations with oxygen and hydrogen are capable of being accurately 

 determined. 



Sulphur and oxygen are held to combine in two definite pro- 

 portions, forming sulphurous and sulphuric acids. In the first, 

 100 parts of sulphur are combined with 100 of oxygen ; in the 

 second, 100 are combined with 150 of oxygen, forming what is 

 called the real acid, with which are further combined 5G*7 of 

 combined water, the entire compound, constituting the acid in 

 the highest state of concentration (1*85 of specific gravity), in 

 which it can be procured in an insulated form. 



This constitution of these compounds appears at first view in 

 opposition to the law of definite proportions in chemical combi- 

 nations ; for, according to that law, the higher proportion of an 

 element in combination with another is a simple multiple of the 

 lower proportion in which it combines with the same body ; and 

 hence, since in the first combination of sulphur with oxygen, 

 100 of the former are combined with 100 of the latter ; in the 

 second, 100 ought to be combined with 200, while the combina- 

 tion is that of 100 to 150. And in the atomic hypothesis, this 

 involves the absurdity of supposing, that while, in the first 

 compound, the combination, in conformity to the common rule, 

 is that of one atom of sulphur with one atom of oxygen ; in the 

 second, it is that of an atom of sulphur with an atom and a half 

 of oxygen. To obviate this, it is supposed that a combination 

 of sulphur with a lower proportion of oxygen exists — an oxide 

 composed of 100 of sulphur with 50 of oxygen. The ratio will 

 then be that of 1, 2, 3, of oxygen in the three compounds to one 

 of sulphur. And in the atomic system, the first will be held to 

 be that of an atom of sulphur with an atom of oxygen ; the 



