The multitude of experiments with mercury yielded many products, and
often the same product by a different process which acquired a distinct
name.
Turbith mineral was a secret preparation with Oswald Crollius who gave
it this name, probably, it is supposed, on account of its resemblance
in colour to the Turbethum (Convolvulus) roots which were in his time
much used in medicine. It is a subsulphate, made by treating mercury
with oil of vitriol and precipitating with water.
The precipitation of mercury by sal ammoniac was first described by
Beguin in 1632. For a time it was given as a purgative and in venereal
diseases. A double chloride of mercury and ammonium was also made by
the alchemists and was highly esteemed by them, especially as it was
soluble. It was called Sal Alembroth and also Sal Sapientiæ. The origin
of the first name is unknown, but it has been alleged to be of Chaldean
birth and to signify the key of knowledge.
A green precipitate was obtained by dissolving mercury and copper
in nitric acid, and precipitating by vinegar. This was also used in
syphilis.
Homberg put a little mercury into a bottle and attached it to the wheel
of a mill. The metal was thereby transformed into a black powder (the
protoxide.)
By a careful and very gradual precipitation of a solution of nitrate of
mercury by ammonia Hahnemann obtained what he called soluble mercury.
Soubeiran proved that this precipitate was a mixture in variable
proportions of sub-nitrate and ammonio-proto-nitrate of mercury.