130 Mr. Chenevix's Observations and Experiments 
It may be observed, that the 53,5 of the retort did not yield 
the same proportion of acid as the 5 of the tube and receiver. 
The fact is, that all muriates lose a little of their acid at a red 
heat, as I shall presently mention more particularly ; and the 
small loss was, in all probability, owing to a portion of acid 
disengaged by the heat to which the salt was necessarily ex- 
posed during the operation. 
Having thus ascertained the proportion of oxygen in hyper- 
oxygenized muriatic acid, by means of its combination with 
potash, a ready method occurred to arrive at the knowledge of 
that contained in oxygenized muriatic acid. For this purpose, 
I disposed in the following manner, a Woulfe s appaiatus, con- 
sisting of three bottles, and connected with the pneumatic tub. 
In the first bottle, I put a solution of potash* in about six parts 
of water. In the second, a solution of the same ; but so dilute, 
as that no part of the salt, which might be formed, should crys- 
tallize during the operation. About twenty parts of water was 
the proportion there employed. In the third bottle, I put common 
carbonate of potash. Through this apparatus, I sent a current 
of oxygenized muriatic acid, disengaged by sulphuric acid, from 
2 l mixture of muriate of soda and black oxide 01 manganese, in 
the well known manner. Crystals of hyperoxygenized muriate 
of potash were formed in the liquor of the first oottle ; and, as 
long as they remained, I was certain, from previous experiment, 
that no sulphuric or muriatic acid could pass into the second 
bottle. The current was continued, till the liquor of that bottie 
contained an excess of acid. The carbonate of potasn, in the 
third bottle, absorbed the superabundant vapours; and the 
* Whenever potash, soda, barytes, an acid, an alkali, water, or the names of other 
substances are used without an epithet, they are meant to denote them in that state 
which is commonly called pure. 
