8^ Sir H. Davy on a new Substance 
metals with much less energy than chlorine, it occurred to 
me, that it w'ould probably be expelled from its combinations 
by that body ; and this I have found to be the case in all the 
experiments I have made. When the compound of the new 
substance and potassium is heated in contact with chlorine, 
potassane (muriate of potassa) is formed, the violet gas ap- 
pears, but soon combines with chlorine, and they form together 
the peculiar acid compound I have before described ; but to- 
wards the end of the process, as the proportion of chlorine 
diminishes, the violet coloured gas again appears. 
When the compound of the substance with silver was treated 
in the same manner (argentane) muriate of silver was formed, 
and the substance combined with chlorine at the commence- 
ment of the operation, but was disengaged uncombined 
towards the end. 
Similar phenomena occurred when the compounds of the 
substance with mercury and lead were acted on by chlorine. 
The action of acids on the compounds of this substance, are 
what might be expected from its analogies to chlorine. 
When concentrated sulphuric acid is poured upon the com- 
pound of the substance and potassium, some of the substance 
appears ; but a part of it rises in combination with hydrogen 
and w ater, and condenses by cold, and appears of a deep orange 
colour from having dissolved some of the substance. The 
sulphuric acid likewise seems to retain some of the substance, 
for it continues red after being strongly heated, and the acid 
is partly decomposed, for sulphurous acid gas is disengaged. 
It seems probable, that the acid is decomposed to furnish oxy- 
gen to a portion of the potassium which quits in consequence 
the new substance, and that water is likewise decomposed to 
