in zoology, the name of an insect produced in the excrescences of a species of the oak.

Kermes, among the Arabians, signifies a small worm; and κερμης among the Greeks, whence the Latin word coccum, both which mean a kernel or grain: for which reason, among the later Greeks, instead of the word κερμης, the word σκόλοπας, a worm, is substituted; for these grains are full of small worms, the juice of which affords the scarlet colour and dye. Hence the worm is taken for the grain itself.

The kermes appears at first wrapped up in a membranaceous bladder, of the size of a pea, smooth and shining, of a brownish red colour, and covered with a very fine ash-coloured powder. This bag teems with a number of reddish eggs or insects, which, being rubbed with the fingers, pour out a crimson liquor. It is only met with in warm countries in the months of May and June. In the month of April this insect becomes of the size and shape of a pea; and its eggs some time after burst from the womb, and, soon turning into worms, run about the branches and leaves of the tree. They are of two sexes, and the females have been hitherto described: but the males are very different from the former; and are a sort of small flies like gnats, with six feet, of which the four forward are short, and the two backward long; divided into four joints, and armed with three crooked nails. There are two feelers on the head, a line and a half long, which are moveable, streaked, and articulated. The tail at the back part of the body is half a line long, and forked. The whole body is covered with two transparent wings, and they leap about in the manner of fleas. The harvest of the kermes is greater or less in proportion to the severity of the winter. The women gather them before sun-rising, tearing them off with their nails, for fear there should be any loss from the hatching of the insects. They sprinkle them with vinegar, and lay them in the sun to dry, where they acquire a red colour.

KERMES Mineral, so called from its colour, which resembles that of vegetable kermes, is one of the most important antimonial preparations, both with regard to its chemical phenomena and to its medicinal uses.

The use of kermes-mineral was not established in medicine before the beginning of this century. Some chemists, indeed, amongst others Glauber and Lemery, had before that time mentioned in their works several preparations of antimony which approach more or less to kermes; but these preparations being little known, were confounded with many others which are entirely neglected, although much praised by their authors.—The fame of kermes was occasioned by friar Simon, apothecary to the Chartreux friars. He received this preparation from a surgeon called La Ligerie, who had procured it from a German apothecary who had been a scholar of the famous Glauber. Friar Simon, from the commendations given to this new remedy by La Ligerie, administered it to a Chartreux friar, who was dangerously ill of a violent periapneumony, by which the friar was suddenly, and as it had been miraculously, cured. From that time the friar-apothecary published the virtue of his remedy. Several other remarkable cures were performed by means of kermes. The public believed in its medicinal qualities, and called it powder of Chartreux; because it was prepared only in the apothecary's shop belonging to these monks. The reputation of kermes extended itself more and more; till at length the duke of Orleans, then regent of France, procured the publication of the process by La Ligerie.

This process consists in boiling, during two hours, pulverized crude antimony in the fourth part of its weight of the liquor of nitre fixed by coals, and twice its weight of pure water; at the end of this time the liquor is to be decanted and filtrated, while boiling, through brown paper. It continues clear while it is boiling hot; but when it cools, it becomes turbid, acquires a red brick colour, and again becomes clear by the deposition of a red sediment, which is the kermes. The boiling may be thrice repeated, and each time the same quantity of water is to be added to the antimony, and a fourth part less of the liquor of fixed nitre. The several sediments from these three boilings are to be added together, washed with clean water till the water acquires no taste; and the kermes is then to be dried. La Ligerie directs, that aquavit shall be once or twice poured upon it and burnt, and the kermes dried again.

We now proceed to explain the nature of kermes, and the phenomena of its preparation.—Crude antimony is composed of regulus of antimony and common sulphur, united naturally with each other, as in almost all metallic minerals. The fixed alkali with which the crude antimony is boiled, although it is diluted with much water, acts upon the sulphur of the antimony, and forms with it liver of sulphur; and as this compound is a solvent of all metallic matters, it dissolves a certain quantity of the regulus of antimony. In this operation then a combination is formed of fixed alkali, of sulphur, and of regulus of antimony. Of these three substances the fixed alkali only is soluble in water, and is the intermediate substance by which the sulphur and regulus are suspended in the water. But we are to observe, that the alkali becomes impregnated by this operation, and by boiling, with a larger quantity of regulus, and especially of sulphur, than can be suspended in cold water; hence the decoction of kermes, which is clear, limpid, and colourless while boiling hot, becomes turbid and deposits a sediment while it cools. This compound, therefore, like certain salts, may be kept dissolved in larger quantity by hot than by cold water, and much of it is therefore deposited by cooling.

Further, while the kermes is precipitating, the whole antimoniated liver of sulphur, which is dissolved by the boiling liquor, may be divided into two parts; one of which, that is the kermes, being overcharged with the regulus, and particularly with the sulphur, contains but a little alkali, which it draws along with it during its deposition. The other part, as it contains much more alkali, remains dissolved even in the cold liquor, by means of this larger quantity of alkali. All these propositions are to be explained and demonstrated by the following observations.

First, when the decoction of kermes is cold, and has formed all its sediment, if, without adding anything to it, it be heated till it boil, it again entirely re-dissolves the kermes; the sediment disappears; the liquor becomes clear, and by cold is again rendered turbid and deposits sediment as before. Thus the kermes may be made to precipitate and to re-dissolve as often as we please.

Secondly, by digesting kermes in aqua-regia, which dissolves its alkali and regulus, the sulphur is separated pure. The acids of aqua-regia form a nitre and a febrifugal salt of Sylvius with the alkali of the kermes; and if a certain quantity of kermes be melted with black flux after having destroyed its sulphur by roasting, a true regulus of antimony may be obtained from it.

These experiments, which were made by Mr Geoffroy, and the detail of which is found in memoirs given to the Academy in the years 1734 and 1735, upon the analysis of kermes, shew evidently the presence of sulphur, of fixed alkali, and of regulus of antimony, in this compound. From Mr Geoffroy's experiments we find, that 72 grains of kermes contain about 16 or 17 grains of regulus, 13 or 14 grains of alkaline salt, and 40 or 41 grains of common sulphur.

Thirdly, by repeating the boiling of the liquor upon the antimony, more and more kermes will be formed each time by cooling, as at first; and this experiment may be repeated a great many times. Mr Geoffroy says, that he repeated it 78 times, without any other addition than that of pure water to supply that which was lost by evaporation; and that each time a considerable quantity of kermes was formed by cooling. This experiment proves, that the alkali transforms the antimony into kermes by overcharging itself with regulus and sulphur, and at each precipitation the kermes does not retain and take with it but a very small quantity of alkali.

Fourthly, if any acid be poured upon the liquor in which the kermes has been formed, and from which it has been entirely separated by cooling, Mr Beaume has observed, that this liquor is again rendered turbid, and that a second sediment is formed of a yellow reddish colour, which is nothing else than golden sulphur of antimony; that is, regulus of antimony and sulphur mixed together, but in very different proportions, and with very different strengths of union, from those in which they are found in the crude antimony.

After this precipitation, in the liquor a neutral salt is left, which is formed by the contained alkali and the precipitating acid. From this experiment we find, that in the liquor from which the kermes has been deposited, a considerable quantity of antimoniated liver of sulphur remains, which differs from kermes by containing a much larger proportion of alkali; so that it can keep dissolved the regulus and sulphur with which it is united, even when the liquor is cold.

In the process for several antimonial preparations, a kermes, or compounds like it, are formed. This always happens when crude antimony is treated by fusion with a quantity of alkaline salt, so that an antimoniated liver of sulphur results from it, overcharged with regulus and sulphur; that is, containing more of these two substances than it can keep dissolved in cold water. If any of these combinations be boiled in water, a matter analogous to kermes is always deposited by cooling. This happens, for instance, to the scoria of the regulus of antimony, and in an operation described by Mr Geoffroy to abridge the process for making kermes by fusion.

To make kermes by fusion, Mr Geoffroy fuses two parts of antimony with one part of alkaline salt; he powders this matter while yet hot, and keeps it during two hours in boiling water; he then filtrates it, and receives the liquor into more boiling water, from which, when it cools, about six gros of kermes is deposited, when an ounce of antimony has been used. This method of making kermes is much more expeditious, but less perfect; for, as the author confesses, the kermes produced is not so fine and soft as that made in the ordinary method.

Mr Lemer the elder mentions also, in his Treatise concerning Antimony, an operation from which his son pretends that kermes may be obtained. This operation consists in digesting, and afterwards boiling, powdered crude antimony in a very pure liquor of fixed nitre. This liquor, if it be in sufficient quantity, is capable of dissolving, quickly and entirely, powdered crude antimony; and we cannot doubt but that, by cooling, a considerable quantity of a substance very analogous to kermes will be produced. Nevertheless, none of these short methods of making kermes is directed by dispensaries, or by the best books for describing the preparations of chemical remedies.

Kermes is used in medicine only; and from it singularly excellent effects may be produced, when administered by able physicians. In kermes are united the exciting and evacuant virtues of the emetic preparations of antimony, with the tonic, dividing, aperitive, and resolving properties of the liver of sulphur; that is to say, that it is capable of answering two principal indications in the treatment of many acute and chronic diseases. Properly managed, it may become an emetic, purgative, a diuretic, a sudorific, or an expectorant, as is required, and it is always attenuating and resolving. When seven or eight grains are taken at once, it chiefly acts upon the prime vie, generally as an emetic and as a purgative. A dose of three or four grains is seldom emetic, and more frequently purgative. When taken in these quantities as an evacuant, a little of it passes also into the vise secundae & tertiae. When it is administered in smaller doses, it passes almost entirely into the lacteal, blood, and lymphatic vessels. In these it occasions such spasms and oscillations