COCHINEAL is extremely rich in the finest red colouring matter, and has been long em ployed in scarlet dyeing, and in the manufac ture of carmine. It consists of a colouring matter, a peculiar animal matter, a fatty substance, and several salts. The chief use of cochineal is the dyeing of scarlet, The fine colour which it yields is converted to this tint by means of chloride or muriate of tin.
The insect which constitutes cochineal feeds chiefly upon Cactus cochenillifera and C. opms tia. The female insect only is collected. Several varieties are distinguished in com merce, and have different degrees of value attached to them, dependent chiefly upon the different methods employed to kill and dry the insects. When dried, they resemble small grains, scarcely so large as a pepper-corn, ovate, convex above, plane below, transversely furrowed, externally blackish brown, but as if dusted with a white powder, light, friable, the internal substance consisting of extremely small grains, obscurely purple, but when re duced to powder of a rich purple. They are inodorous, but with a bitter sweet acrid taste. They impart to water or alcohol by digestion an intensely red colour.
Cochineal has hitherto been employed mostly as a colouring material, either of tinc tures, or of other things, the nature of which it is wished to disguise; but it is also used to a small extent in medicine.
Previous to the revolt of the Spanish Ame rican provinces, almost all the trade in cochi neal with the different markets of Europe was carried on through Spain, and chiefly through Cadiz ; but since that event the markets of consumption are supplied with cochineal either direct from the places of pro duction, or from neighbouring stations, to which the article has found its way in the natural course of commerce. Representing a considerable value in a small bulk, cochineal is frequently used, with great convenience to merchants, as a medium for making remit tances, and hence the comparatively circuitous route by which the greater part of it reaches the places of ultimate consumption. The quantity of cochineal imported into Great Britain in 1848 was 18,380 cwt; of which Hon duras yielded 9139 cwt., and Mexico 605-t cwt.