204 On the Connexion which exists between 
the oxygen, is avery simple method of determining the 
proportions of al] the metallic salts. With the exception of 
the proportions of the insoluble salts, those of all the rest 
present an uncertainty more or less great; and it would be 
useful to make it disappear, by making the proportions of 
acid in the metallic salts depend on those of the oxygen 
contained in their oxides. It is sufficient, in fact, to know 
the various degrees of oxidation of the metals, to conclude 
from them the relative quantities of acid which they re- 
quire to saturate themselves ; and in order to have the ab- 
solute quantities, it 1s sufficient to know the proportions of 
any salt in each genus. 
T shall take as a first example the muriates, and [I shall 
suppose, on weighing the experiments of several chemists 
with mine, that the muriate of silver contains : 
GIVER ALLE eee ere 
Oxvred se 22'.4% "4 dee Weibel ay ROO 
POAC snot gees «Shs none bas o> Moe 
On the other hand, 
100 of copper taxes 24°57 oxygen fF according to my 
PMC ihe of cso wile we Sa } experiments. 
Lead ........6.-+.° 7°29 ———~—_ Mz. Berthier. 
Mercury at the minimum 4°16 { ——— Messrs. Fourcroy 
Ditto . at the maximum 8°21 | - and Thenard. 
If we admit these data, and the principle that the capa- 
cities of the metals for the acids are proportional to the quan- 
tity of oxygen which they contain, we find the following 
proportions for the muriates which are deprived of water : 
100°00 lead. 
Muniate of lead ... 7°29 oxygen. 
24°68 acid. 
Mr. Kirwan has found for this salt 24°02 of acid. If 
we calculate the proportion of this last according to the 
analysis of the sulphate of lead by M. Berthier, and accord- 
ing to the relation of the capacities of the muriatic acid and 
sulphuric acid deduced from the analysis of the sulphate 
and the muriate of barytes, by the same chemist, we find 
24°55; which agrees very exactly with the number 24°68 
which [ have given. 
100°00 copper. 
Muriate of copper. 4 G4°57 oxygen. 
83°18 acid. 
Instead of this number M. Proust has found 74°74. 
160°00 copper. 
White muriate of copper / 12°98 oxvgen. 
41°59 acid. 
Messrs. 
