60 ON THE ADULTERATION OF COCHINEAL. 
tervals with water, threw it away as completely exhausted. 
M. Lembine, a dyer of Rouen, was, I believe, the first 
whom the idea struck of ascertaining if this cochineal, 
which the cotton-printers threw away, was entirely deprived 
of its coloring principle. He found that it still contained 
from about 15 to 18 per cent. The dyer now buys this 
residue from the cotton-printer, at the price of from Is. 6d. 
to 2s. 6d. the 2 lbs. ; he dries it, spreads it in thin layers in 
a well-aired place, and preserves it in barrels for use. This 
cochineal having begun to undergo decomposition during 
its desiccation, always has a smell of putrified animal mat- 
ter; it is black, quite without form, often agglomerated into 
more or less large masses. 
Down of Cochineal. — We sometimes find a gray light 
substance in commerce, mixed with a great quantity of 
small black granules hard to the touch ; this substance is 
known by the name of down, or cochineal siftings. MM. 
Fee, Boutron Charlard, Bussy and Guibourt, who have 
written on this insect, do not speak of this product. It 
contains about 20 per cent, of coloring matter. 
These two products have lost much of the preference which 
dyers used to give them on account of the low price at which 
they were to be bought ; because in order to obtain as beauti- 
ful a tint and as dark a one with them as that obtained with 
pure cochineal, three or four times as much matter is necessa- 
ry, to which must always be added a small quantity of unex- 
hausted cochineal ; secondly, because this matter fills up the 
vats, and is very hard to detach from the tissue. 
I owe to the kindness of the merchants of this town thirty 
specimens of cochineal, on which I have made experiments. 
In the houses which carry on a wholesale trade in this com- 
modity, I have constantly found the same kinds of cochineal : 
the pure gray cochineal, No. 1, or gray cochineal of the Cana- 
ries, the blackish gray or zacatillee cochineal, No. 2, and the 
black or zacatillee cochineal, No. 3. This last is adulterated ; 
merchants buy it as such. According to the information I 
