C 214 D 
XIII. On the action of acids on the salts usually called hyperoxy- 
muriates, and on the gases produced from them. By Sir 
Humphry Davy, LL.D. F.R.S. 
Read May 4, 1815. 
The effects produced when concentrated hydro-sulphuric 
acid (oil of vitriol) is poured upon hyperoxymuriate of potassa, 
have been often objects of chemical discussion ; the acid and 
the salt, it is well known, become deep orange, and if any 
moisture is present, or if heat is applied to the mixture, a 
detonation occurs. In a paper read before the Royal Society, 
I have ventured to suppose, that these phenomena depend 
upon the developement and sudden decomposition of the 
compound of chlorine and oxygene, which I have named 
euchlorine. 
A statement, which I understand has been made by M. Gay 
Lussac, namely, that a peculiar acid, which he has called 
chloric acid, may be procured from the hyperoxymuriate of 
baryta by sulphuric acid, led me to examine the action of 
acids on the hyperoxymuriates under new circumstances, 
and I have made some observations which appear to me not 
unworthy of being communicated to the Royal Society. 
If 30 or 40 parts of sulphuric acid be poured upon one part 
of dry hyperoxymuriate of potassa in a wine glass, and the 
salt be agitated in the acid, there is a very slight effervescence 
only, the acid becomes of a deep orange tint, and white 
