little nitrat of barytes, so long as any precipitation takes place; the
sulphuric acid, from its greater affinity, attracts the barytes, and
forms with it an insoluble neutral salt, which falls to the bottom. It
may be purified in the same manner from muriatic acid, by dropping in a
little nitrat of silver so long as any precipitation of muriat of silver
is produced. When these two precipitations are finished, distill off
about seven-eighths of the acid by a gentle heat, and what comes over is
in the most perfect degree of purity.
The nitric acid is one of the most prone to combination, and is at the
same time very easily decomposed. Almost all the simple substances, with
the exception of gold, silver, and platina, rob it less or more of its
oxygen; some of them even decompose it altogether. It was very anciently
known, and its combinations have been more studied by chemists than
those of any other acid. These combinations were named _nitres_ by
Messrs Macquer and Beaume; but we have changed their names to nitrats
and nitrites, according as they are formed by nitric or by nitrous acid,
and have added the specific name of each particular base, to distinguish
the several combinations from each other.
TABLE _of the Combinations of Sulphuric Acid with the Salifiable Bases,
in the order of affinity._
_Names of the bases._ _Resulting compounds._
_New nomenclature._ _Old nomenclature._
Barytes Sulphat of barytes Heavy spar. Vitriol of heavy earth.
Potash potash {Vitriolated tartar. Sal
{ de duobus. Arcanum
{ duplicatam.
Soda soda Glauber's salt.
Lime lime Selenite, gypsum, calcareous vitriol.
Magnesia magnesia Epsom salt, sedlitz salt, magnesian vitriol.
Ammoniac ammoniac Glauber's secret sal ammoniac.
Argill argill Alum.
Oxyd of zinc zinc {White vitriol, goslar
159