combinations of Oxy muriatic Gas and Oxygene , &c. 27 
T wo grains of white oxide of arsenic absorbed 0.8 of oxy- 
muriatic gas.* 
I doubt not that the same phenomena will be found to occur 
In other instances, in which the metal has comparatively a 
slight attraction only for oxymuriatic gas, and when it is sus- 
ceptible of different degrees of oxydation, and in which the 
peroxide is used. 
The only instance in which I tried to decompose a common 
metallic oxide, by muriatic acid, was in that of the fawn 
coloured oxide of tin ; water rapidly separated, and Libavius’s 
liquor was formed. 
From the proportions which may be gained in considering 
the volumes of oxymuriatic gas absorbed by the different me- 
tals, in their relations to the quantity of oxygene which would 
be required to convert them into oxides, it would appear, that 
in the experiments to which I have referred, either one, two, 
or three proportions of oxymuriatic gas combine with one of 
metal, and consequently, from the composition of the muriates, 
it will be easy to obtain the numbers representing the pro- 
portions in which these metals may be conceived to enter into 
other compounds.'!' 
* A singular instance of the tendency of the oxide of arsenic to become arsenical 
acid, occurs in its action on fused hydrat of potash, the water in the hydrat is rapidly 
decomposed, and arseniuretted hydrogene evolved, and arseniate of potash formed. 
f From the experiments detailed in the note in the opposite page, it would appear 
that the number representing the proportion in which mercury combines must be 
about 200. That of silver, as would appear from the results, page 25, about ioo. 
The numbers of other metals may be learnt from the data in the same page, but from 
what has been stated, these data cannot be considered as very correct. 
