nomenclature of the acids would not have been at all perplexed, as it is
now in the old nomenclature, if the base or radical of each acid had
been known when the acid itself was discovered. Thus, for instance,
phosphorus being a known substance before the discovery of its acid,
this latter was rightly distinguished by a term drawn from the name of
its acidifiable base. But when, on the contrary, an acid happened to be
discovered before its base, or rather, when the acidifiable base from
which it was formed remained unknown, names were adopted for the two,
which have not the smallest connection; and thus, not only the memory
became burthened with useless appellations, but even the minds of
students, nay even of experienced chemists, became filled with false
ideas, which time and reflection alone is capable of eradicating. We may
give an instance of this confusion with respect to the acid sulphur: The
former chemists having procured this acid from the vitriol of iron, gave
it the name of the vitriolic acid from the name of the substance which
produced it; and they were then ignorant that the acid procured from
sulphur by combustion was exactly the same.
The same thing happened with the aeriform acid formerly called _fixed
air_; it not being known that this acid was the result of combining
charcoal with oxygen, a variety of denominations have been given to it,
not one of which conveys just ideas of its nature or origin. We have
found it extremely easy to correct and modify the ancient language with
respect to these acids proceeding from known bases, having converted the
name of _vitriolic acid_ into that of _sulphuric_, and the name of
_fixed air_ into that of _carbonic acid_; but it is impossible to follow
this plan with the acids whose bases are still unknown; with these we
have been obliged to use a contrary plan, and, instead of forming the
name of the acid from that of its base, have been forced to denominate
the unknown base from the name of the known acid, as happens in the case
of the acid which is procured from sea salt.
To disengage this acid from the alkaline base with which it is combined,
we have only to pour sulphuric acid upon sea-salt, immediately a brisk
effervescence takes place, white vapours arise, of a very penetrating
odour, and, by only gently heating the mixture, all the acid is driven
off. As, in the common temperature and pressure of our atmosphere, this
acid is naturally in the state of gas, we must use particular
precautions for retaining it in proper vessels. For small experiments,
the most simple and most commodious apparatus consists of a small retort
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