Potash Pyro-mucite of potash.
Soda soda.
Barytes barytes.
Lime lime.
Magnesia magnesia.
Ammoniac ammoniac.
Argill argill.
Oxyd of
zinc zinc.
manganese manganese.
iron iron.
lead lead.
tin tin.
cobalt cobalt.
copper copper.
nickel nickel.
arsenic arsenic.
bismuth bismuth.
antimony antimony.
[Note A: All these combinations were unknown to the ancient
chemists.--A.]
SECT. XXXI.--_Observations upon Pyro-mucous Acid, and its Combinations._
This acid is obtained by distillation in a naked fire from sugar, and
all the saccharine bodies; and, as these substances swell greatly in the
fire, it is necessary to leave seven-eighths of the retort empty. It is
of a yellow colour, verging to red, and leaves a mark upon the skin,
which will not remove but alongst with the epidermis. It may be procured
less coloured, by means of a second distillation, and is concentrated by
freezing, as is directed for the citric acid. It is chiefly composed of
water and oil slightly oxygenated, and is convertible into oxalic and
malic acids by farther oxygenation with the nitric acid.
It has been pretended that a large quantity of gas is disengaged during
the distillation of this acid, which is not the case if it be conducted
slowly, by means of moderate heat.
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