a4 On definite Proportions. 
is disengaged, and a precipitate of revived sulphur appears. We 
may therefore safely assume, that of the four stages of oxygeniza- 
tion of sulphur, only one is capable of being separately exhibited. 
Nor can the zitric acid be obtained without water. If we 
attempt it, we get nothing but oxygen gas and nitrous acid. But 
when these gases come into contact with each other over water, 
the affinity between the substances, which had been suspended, 
is restored, and a compound of nitric acid and water is formed. 
Consequently the nitric acid cannot exist alone, but requires the 
presence of a third body containing oxygen. If the nitric acid 
were incapable of being exhibited in a lower degree of oxygeni- 
zation, and if the affinity of oxygen to its radical were very strong, 
it would obviously be perfectly impossible to expel this acid from 
any of its combinations by means of a dry, although a stronger, 
acid, with the assistance of heat; for im this case two strong 
affinities would oppose the one which tends to the formation of 
the dry acid; that is, the attraction of the nitric acid to the base 
of the combination, and that of the oxygen to the radical of the 
acid, which must both be overcome in order that the separation 
may take place. 
But it often happens that the attraction of a radical to oxygen 
is incomparably greater than that of an acid to a base. It is 
therefore very natural, that an acid which cannot be exhibited in 
a separate state, and of which the radical has a very strong at- 
traction for oxygen, should be incapable of being separated from 
its combinations without the intervention of water, or of some 
other oxidated body. : 
This is precisely the case with the muriatic acid, and it pos- 
sesses the properties which have led the acute Mr. Davy to his 
peculiar opinions respecting this acid, in common with the sul- 
phuric, the nitric, and, as we shall see hereafter, with several 
other acids. The experiments, which have been performed, in 
order to the decomposition of the muriatic acid, prove that the 
radical of this acid has a remarkably powerful attraction for oxy- 
gen, if not the greatest of all existing substances. But if we 
attempt to decompose ignited muriate of soda with fused boracic 
acid in ared heat, we oppose the weak attraction between the 
boracie acid and the alkali to the much stronger attraction of the 
muriatic acid for the alkali, and the still more powerful affinity 
of the radical of the acid to oxygen: hence it is very obvious 
that no separation of the muriatic acid from the base can take 
lace. 
‘ When the celebrated Mr. Davy entertained hopes of decom~ 
posing the oxymuriatic acid gas by means of charcoal, which he 
kept ignited in it for an hour, he seemed to suppose that the 
earbon had a greater affinity for oxygen than the radical of the 
murtatic? 
