Among the important discoveries made by accident, the following in the history of Cochineal may be instanced: "The well-known Cornelius Drebbel, who was born at Alcmaar, and died at London in 1634, having placed in his window an extract of Cochineal, made with boiling water, for the purpose of filling a thermometer, some aqua-regia dropped into it from a phial, broken by accident, which stood above it, and converted the purple dye into a most beautiful dark red. After some conjectures and experiments, he discovered that the tin by which the window frame was divided into squares had been dissolved by the aqua-regia, and was the cause of this change. He communicated his observation to Kuffelar, an ingenious dyer at Leyden. The latter brought the discovery to perfection, and employed it some years alone in his dye-house, which gave rise to the name of Kuffelar's color."[905]
That innocent cosmetic, so much used by the ladies, and commonly known by the French term Rouge, is no other than a preparation of Cochineal.[906]
Kermes-berries, _Coccus ilicis_, and Cochineal, _C. cacti_, Geoffroy says, "are esteemed to be greatly cordial and sudorific, being very full of volatile salt. They are given also to prevent abortion from any strain or hurt."[907]
_Lac_ is the produce of an insect supposed by Amatus Lusitanus to be a kind of ant, and by others a bee, but now ascertained to be a species belonging to the Coccidæ--the _Coccus ficus_ or _C. lacca_. It is collected from various trees in India, where it is found so abundantly, that, were the consumption ten times greater than it is, it could be readily supplied.
Lac is known in Europe by the different appellations of _stick-lac_, when in its natural state, adhering to, and often completely surrounding, for five or six inches, the twigs on which it is produced by the insects contained in its cells; _seed-lac_, when broken into small pieces, garbled, and the greater part of the coloring matter extracted by water; when it appears in a granulated form; _lump-lac_, when melted and made into cakes; and _shell-lac_, when strained and formed into transparent laminæ.
Lac, in its different forms, is made use of in the manufacture of varnishes, japanned ware, sealing-wax, beads, rings, arm-bracelets, necklaces, water-proof hats, etc., etc. Mixed with fine sand it forms grindstones; and added to lamp or ivory black, being first dissolved in water with the addition of a little borax, it composes an ink not easily acted upon by dampness or water. It has been applied also to a still more important purpose, originally suggested by Dr. Roxburgh about the year 1790--that of a substitute for Cochineal in dyeing scarlet.[908] From this suggestion, under the direction of Dr. Bancroft, large quantities of a substance termed _lac-lake_, consisting of the coloring matter of stick-lac precipitated from an alkaline lixivium by alum, were manufactured at Calcutta and sent to England, where at first the consumption was so great, that, according to the statement of Dr. Bancroft, in 1806, and the two following years, the sales of it at the India House equaled in point of coloring matter half a million of pounds' weight of Cochineal. Soon after this, a new preparation of lac color, under the name of _lac-dye_, was substituted for the lac-lake, and with such advantage, that in a few months £14,000 were saved by the East India Company in the purchase of scarlet cloths dyed with this color and Cochineal conjointly, and without any inferiority in the color obtained.[909]