14.1.18

Cochineal.

Scientific American 51, 8.9.1849

This beautiful dye drug, is an insect, the Coccus Cacti of Linæus. When first introduced into Europe, it was thought to be a vegetable seed. It lived upon the cactus, and the greatest quantity of it used to be raised in Mexico. Two kinds of it are gathered, the one wild the other cultivated; the wild is inferior to the cultivated kind. The males of the insect have wings and are seldom found in the cochineal of commerce. The female insect has no wings; she is of a reddish brown color, with a hemispherical wrinkled back. The species of cactus on which the cochineal insect attains to the greatest perfection is named the cactus cochenillifer. It has red and crimson colored fruits. When the Spaniards arrived in Mexico, the yfound the natives well acquainted with the use of cochineal as a coloring drug. In 1759, John Ellis, F. R. S., of London, received from Dr. A. Garden, of Charleston, S. C., some joints of the cactus with the nests of the insects upon it, which were laid before the royal society, and along with the plant and insects, Dr. Garden sent a very minute description of his investigations into the habits and form of the insect. There are two varieties of the true nopal cacti in Mexico, on which the insect is raised, but the wild kind when cultivated and raised upon the special kind (Castilian Nopal), becomes about half as good as the other. The nopals or cacti on which the cochineal insects are raised, are not covered with hard thorns like most of the cacti or prickly pear - the name by which it is generally known, - the thorns at least are quite soft, rendering tem accessible to collect the cochineal.

There is one male for about 3000 females, it is supposed; great care is taken to destroy those that are to be used as a drug, at the time they are about to bring forth their young. The insects are stripped from the plants by laying down cloths and drawing the dull blade of a knife between the under surface of a branch of the nopal and the clusters of the insects on it. They are then killed by steaming them in the cloth, or dipped in scalding water, and then spread out to dry in the sun. To preserve the stock of cochineal insects, they are secured on the plant from wind and rain in the wet seasons, by covering them up with matting; but the wild insects need no such care, and they propagate quicker, giving six crops in one year, while the cultivated superior gives only three. Where the wild and cultivated are raised on one plantation, the two kinds are kept separate, so that the one kind may bot amalgamate with the other. The delicate superior cochineal has attained to its present perfection by long care, through many generations, both by the INdians and Spaniards. It is generally allowed that the color of the cactus has nothing to do with the color of the insect, as it feeds not on the red fruit, but upon the branches. There has always been a very great demand for cochineal, yet from 1790 to 1835, the increase of importations by Europe only amounted to 18,320 lbs. In 1791, 400,000 pounds were imported, and in 1835, 418,320. The cochineal sold in London is often adulterated with what is called the East India cochineal, a worthless insect; but we are not troubled with such adulterations in the United States, although a great deal of very inferior stuff is sold. The best cochineal is a full and plump insect of a crimson brown color, having a whitish cilor in the wrinkles on its back, wich run across the same and are intersected with a central longitudinal furrow.

In Clavigero's History of Mexico it is stated that the ancient inhabitants of Mexico obtained a purple color from cochineal. This was doubted for a long time in Europe, but with a mordaunt of alum and a small portion of iron, it can produce a purple; this, however, is not the common way to produce this color, cochineal is used to dye the most brilliant of all colors, the scarlet on silk and wool. It is used to impart athe ruby blush to the cheek of the vain one, who dreams not, while she flaunts her borrowed beauty, that she is indebted for it to an humble insect. Red can be dyed on silk and woold with ground cochineal, by first impregnating the fabric with a solution of alum. A more brilliant color is produced by a mordaunt of the chloride of tin and cream of tartar. The beautiful pigment, carmine, is made from cochineal, and a very chaste pink is dyed upon cotton, but first impregnating the cotton with a solution of sugar of lead. Owing to the hight price of cochineal another drug named lac is much used as a substitute for it. It is imported from India and is much cheaper, althouh far inferior in point of brilliancy of color. Were it possible, and we think it is, to raise cochineal for one dollar per pound, we would not depend upon India for her lac as a dye drug. The cultivation of cochineal is something which should arrest the attention of our people, especially, since we have recently extended our sway over some territory, which, no doubt, can yield it in perfection. As far back as 1793, the sale of it, exported from the Spanish colonies to Europe, amounted to $3,000,000. It may be said that every pound of it that could be raised, would add $1,25 at least, to the wealth of our country. This subject, then, is certainly worthy of much attention.

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