argill.
Oxyd of zinc zinc.
iron iron.
manganese manganese.
cobalt cobalt.
nickel nickel.
lead lead.
tin tin.
copper copper.
bismuth bismuth.
antimony antimony.
arsenic arsenic.
mercury mercury.
silver silver.
gold gold.
platina platina.

_Note._--All the succinats were unknown to the ancient chemists.--A.

SECT. XXXV.--_Observations upon Succinic Acid, and its Combinations._

The succinic acid is drawn from amber by sublimation in a gentle heat,
and rises in a concrete form into the neck of the subliming vessel. The
operation must not be pushed too far, or by too strong a fire, otherwise
the oil of the amber rises alongst with the acid. The salt is dried upon
blotting paper, and purified by repeated solution and crystallization.

This acid is soluble in twenty-four times its weight of cold water, and
in a much smaller quantity of hot water. It possesses the qualities of
an acid in a very small degree, and only affects the blue vegetable
colours very slightly. The affinities of this acid, with the salifiable
bases, are taken from Mr de Morveau, who is the first chemist that has
endeavoured to ascertain them.

SECT. XXXVI.--_Observations upon Benzoic Acid, and its Combinations with
Salifiable Bases[48]._

This acid was known to the ancient chemists under the name of Flowers of
Benjamin, or of Benzoin, and was procured, by sublimation, from the gum
or resin called Benzoin: The means of procuring it, _via humida_, was
discovered by Mr Geoffroy, and perfected by Mr Scheele. Upon benzoin,
reduced to powder, pour strong lime-water, having rather an excess of
lime; keep the mixture continually stirring, and, after half an hour's
digestion, pour off the liquor, and use fresh portions of lime-water in
the same manner, so long as there is any appearance of neutralization.
Join all the decanted liquors, and evaporate, as far as possible,
without occasioning cristallization, and, when the liquor is cold, drop
in muriatic acid till no more precipitate is formed. By the former part
of the process a benzoat