on the Nature of certain Bodies. 83 
inflammable body, the pure basis of the acid ? or is it not like 
sulphur and phosphorus, compounded ? 
'Without entering into any discussion concerning ultimate 
elementary matter, there are many circumstances which favour 
the idea, that the dark olive substance, is not a simple body ; 
its being non-conducting, its change of colour by being heated 
in hydrogene gas, and its power of combining with the alka- 
lies ; for these properties in general belong to primary com- 
pounds, that are known to contain oxygene. 
I heated the olive coloured substance with potassium, there 
was a combination, but without any luminous appearance, and 
a gray metallic mass was formed ; but from the effect of this 
upon water, I could not affirm that any oxygene had been 
added to the metal, the gas given off had a peculiar smell, and 
took up more oxygene by detonation than pure hydrogene, 
from which it seems probable, that it held some of the com- 
bustible matter in solution. 
It occurred to me, that if the pure inflammable basis were 
capable of being deoxygenated by potassium, it would pro- 
bably possess a stronger affinity for oxygene, than hydrogene, 
and therefore be again brought to its former state by water. 
I made another experiment on the operation of potassium, on 
the olive coloured substance, and exposed the mixture to a 
small quantity of ether, hoping that this might contain only 
water enough to oxygenate the potassium ; but the same re- 
sult occurred as in the last case ; and a combination of potash 
and the olive coloured substance was produced, insoluble in 
ether. 
I covered a small globule of potassium, with four or five 
times its weight of the olive coloured matter, in a platina tube 
M 2 
