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concentrated filtrate dried in a water bath, a quantity of a crys- 
talline mass of p. carminic acid is obtained. The p. carminic 
collects like a dense brownish purple glaze on the evaporating 
dish of the water-bath, and on being scraped off with a sharp 
knife, assumes the form of a crystalline powder, full of shining 
scaly crystals. It is very soluble, and the colour of the solution 
a purplish red, or yellowish red, if all the sulphuretted hydrogen 
has not been absorbed and any part of it left to be transformed 
into sulphurous and then sulphuric acid. 
If to the solution of p. carminic acid a little ammonia be 
added, the liquor assumes a rich lake or wine colour very diffe- 
rent from the deep crimson of the solution of ¢. carminic acid in 
ammonia. 
(12) Ifto the solution of common carmine in ammonia diffused 
through sufficient water, freshly precipitated gelatinous alumina 
be added, a beautiful crimson lake of the colour of a crimson rose 
or boiled red beet-root is obtained; but if to the solution of p. 
carminic acid in ammonia, or to the carmine liquor neutralised 
after all the carmine has been got out of it, gelatinous alumina 
be added, a lake-coloured lake, paler, purpler, and weaker and 
altogether of another tint, is the result. 
(13) If the liquor in ($) from which the c. carminie acid 
was precipitated by acetic acid be neutralised, and then acetate 
of lead be added, a copious precipitate of the p. carminate of lead 
follows. 
(14) The p. carminate of lead is decomposed by phosphoric 
acid, and p. carminic acid results, but from the few experiments 
that I made, I inferred that not the whole of the p. carminate 
was thus acted on, only a part, and a reddish precipitate of a 
mixture probably of phosphate of lead and a double phosphate 
and p. carminate of lead remained. 
(15) Sulphuric acid seemed entirely to decompose the 
c. carminate of lead, and the c. carminic acid it contained as 
well, a variable quantity of p. carminic being formed at the same 
