85 
which becomes a violet coloured Gas by Heat, 
furnish hydrogen to another portion of the substance, and that 
the hydrogen and the substance, in their acid form, combine 
W'ith the water of the sulphuric acid, and rise in vapour, sul- 
phate of potassa being at the same time produced. 
When sulphuric acid is poured on the salt consisting of the 
substance, oxygen, and potassium, the substance reappears, 
and there is a slight etfervescence. In this case, part of the 
oxygen is employed to form potassa, and the remainder is 
expelled unaltered. 
When concentrated nitric acid is made to act on the triple 
compound, similar phenomena occur, and the substance reap- 
pears with effervescence. 
When nitric acid is applied to the double compound, there 
is a smell of nitrous gas, and the substance is instantly repro- 
duced. 
With concentrated muriatic acid, the phenomena presented 
by the two different alkaline compounds, the binary and the 
triple, are very interesting. When the acid is brought in con- 
tact with the triple salt, there is no effervescence, but a sub- 
stance, which appears to be a compound of chlorine and the 
new body, is formed and dissolved in the water of the acid, 
and potassane is precipitated. 
When the double compound is used, there is a complete 
solution with a partial decomposition, and by applying a gentle 
Iieat, the excess of muriatic acid is driven off, and the saine 
acid as that procured by the action of the substance on hydro- 
gen remains dissolved in the liquor. When mixtures of the 
two salts arc employed, tlie substance itself appears. 
It appears that in the instance when the triple compound 
is employed, there is not only sufficient oxygen to attract the 
hydrogen from the chlorine which is to couibine with the 
