the Decomposition of the Earths, &c. 06 7 
water, the inflammable body is less compounded, than the 
uninflammable substance resulting from its combustion. 
Potassium I find may be produced readily from dry ignited potash in electrical ex- 
periments ; and the result of the combustion of potassium in oxvgene gas is an alkali, 
so dry that it produces violent heat, and ebullition when water Is added to if. 
In M.M. Gay Luss ac’s and Th enard’s experiment on the action of potassium 
on ammonia, the hydrogene disengaged in the first process, and that existing in the 
ammonia disengaged in the second process, exactly equals the whole quantity con- 
tained in the ammonia. But there is no proof of any hydrogene being disengaged 
from the potassium, for the ammonia lost is not generated, nor potash formed, but by 
the addition of a substance, consisting of oxygene and hydrogene ; and as the three 
bodies concerned in this experiment are potassium, ammonia, and water, the result 
ought to be potash, ammonia, and a quantity of hydrogene, equal to that evolved by 
the mere action of water on potassium, which is said to be the case. 
Even if there were no other proofs, the chemical properties of potassium are so 
wholly unlike those that might be expected from a compound of potash and hydro- 
gene, that they are almost sufficient to decide the question. Potassium acts upon water 
with much more energy than potash, and produces much more heat in it ; and yet if a 
compound of hydrogeae, the affinity of potash for water must be diminished by its 
affinity for hydrogene, to say nothing of the quantity of heat, which ought (on the 
common theory of capacity for heat) to be carried off by this light inflammable gas. 
Potassium burns in carbonic acid, and precipitates charcoal from it ; whereas 
hydrogene electrized with carbonic acid, converts it into gaseous oxide of carbon. 
Potash has a very slight attraction for phosphorus ; but potassium has a very 
strong affinity for it, so as to separate it from hydrogene, and according to M.M. 
Gay Lussac and Thenard, with the phenomena of inflammation. Potash 
has no affinity for arsenic, yet from the experiments of these gentlemen, it appears 
that potassium separates arsenic from arseniated hydrogene ; and hydrogene, which is 
supposed by them to exist in both compounds, can have no affinity for hydrogene, 
nor can hydrogene in one form, be supposed capable of separating arsenic from hydro- 
gene in another form. 
Could not the experiment of M. M. Gay Lussac and Thenard be explained, 
except on the supposition of the hydrogene being derived from the potassium, it would 
be a distinct fact in favour of the revival of the theory-of phlogiston. It would not 
prove, however, that potassium is composed of hydrogene and potash, but that it is 
composed of hydrogene and an unknown basis j and that potash is this basis united 
to water. 
