82 
Sir H. Davy o?i a new Substance 
same manner a solution of nitrate of silver. This peculiar 
acid, which consists of the substance united to hydrogen, has 
a very strong attraction for water, and a very small quantity 
of water absorbs a large quantity of the gas, and when com- 
bined with water, it rises with it in vapour, and in its state of 
liquid acid, it rapidly dissolves the substance, and becomes 
tawny. 
The new substance, as M. M. Desormes and Clement have 
shewn, is rapidly soluble in solution of potash ; when it is in 
excess the solution becomes red brown. On evaporating the 
mixture and heating it to redness, a substance is formed, ex- 
actly similar to that produced by the combination of the sub- 
stance v/ith potassium. 
As potassa is a compound of potassium and oxygen, it is 
evident that, to form a compound of potassium and the sub- 
stance from potassa, oxygen must be expelled, and I found 
by experiment, that this was the case ; and in investigating 
minutely the action of fixed alkaline solutions on the substance, 
I ascertained the existence of a class of substances, precisely 
similar to the hyperoxy muriates, consisting of oxygen, the 
substance, and potassium, and formed in a manner exactly 
analogous. 
If the substance is thrown into a moderately strong solution 
of potassa as it dissolves, crystals fall down, and by saturat- 
ing the solution with the substance, considerable quantities are 
obtained. By pouring off the mother liquor and evaporating 
it a little, more of the crystals fall down. 
All these crystals, if precipitated from a solution not too 
much saturated, are of the same kind, they are little soluble 
in water, have a taste analogous to that of the hyperoxymu- 
