21.3.11

A Dictionary of Arts (supplement): Carmine. Chromium, oxide of. Cochineal.


(A Dictionary of Arts, Manufactures, and Mines; containing A Clear Exposition of Their Principles and Practice)
Recent improvements in
Arts, Manufactures, and Mines:
Being A supplement to his Dictionary
by Andrew Ure, M. D.,
F.R.S. N.G.S. M.A.S. LOND.; M. ACAD. N.S. PHILAD.; S. PH. SOC.N. GERM. HANOV.; MUHL. ETC., ETC.

Illustrated with one hundred and ninety engravings.

New York: D. Appleton & Company, 200 Broadway.  Philadelphia: George S. Appleton, 148 Chestnut St.
MDCCCXLVII
1847

CARMINE. This valuable pigment is often adulterated with starch. Water of ammonia enables us to detect this fraud by dissolving the pure carmine, and leaving the starchy matter, as well as most other sophisticating substances. Such debased carmine is apt to spoil with damp.

CHROMIUM, OXIDE OF. Mix intimately 45 parts of gunpowder with 240 parts of perfectly dry chromate of potash, and 35 parts of hydrochlorate of ammonia (sal ammoniac), reduce to powder, and pass through a fine sieve; fill a conical glass or other mould with this powder, gently pressed, and invert so as to leave the powder on a porcelain slab of any kind. When set on fire at its apex with a lighted match, it will burn down to the bottom with brilliant corruscations. The black residuum, being elutriated with warm water, affords a fine bright green oxide of chromium.

COCHINEAL. Imported for consumption in 1839, 396,902 lbs.; in 1840, 325,744; duty, 1s. per cwt.

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