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Honduras black also yields a good carmine, but I prefer the 
Mexican cochineals. 
Take 840 grains of the best cochineal ; grind it well in a por- 
celain, not metal, mortar to a powder of the fineness of ground 
coffee or snuff. Intimately mix with it by grinding 40 grains of 
whitening, t.e. washed chalk or carbonate of lime. Set a 5 quart 
tinned iron saucepan, size No. 8, filled to about an inch of the 
top with rain water, on the fire to boil. This will contain about 
4 to 43 quarts. Before boiling, throw in 8 grains of bicarbonate 
of ammonia (carbonate of ammonia of the shops exposed for a 
few days to the air), and 5 grains of oxalate of ammonia (to 
precipitate any lime that the rain-water may have taken up from 
the roof of the house); when the water boils remove the saucepan 
from the fire, add about half an ounce of cold rain-water to 
throw the “ water off the boil,” then stir in the mixture of cochi- 
neal and whitening. Replace the lid, and leave the saucepan 
for about 8 or 9 minutes near the fire on the fender, so as to keep 
the temperature as nearly constant as possible, and just a little 
under the boiling point. At the end of the 8 or 9 minutes 
sprinkle in slowly, little by little at a time, stirring all the while 
with a clean wooden rod, from 37 to 40 grains of finely powdered 
chemically pure alum. Then transfer the contents of the sauce- 
pan to a conical tin vessel, provided with a handle and lip; a 
milk-can will answer very well. This vessel ought previously 
to have been warmed with scalding water. Cover the can with 
a wooden or pasteboard cover, or the lid of a cigar box, &c., 
mutile the whole up in a cloth to keep in the heat, and leave it 
just outside the fender in front of the fire for about from 15 to 
20 minutes. By this time, to quote from Ure, the “bath will be 
as clear as though it had been filtered,” and of a bright scarlet 
colour. Decant cautiously about 2rds of the contents into a 
clean tinned iron saucepan, add about half an ounce fluid 
measure of a solution of the white of one egg in 16 ounces of 
water (the solution must previously have been strained through 
