in which quinine would be inadmissible. A medical correspondent informs us that he has used it with signal success in hay asthma. Another advantage it has over quinine is, it is much lower in price. Quinetum, according to Dr de Vrij’s process, as well as a sulphate and hydrochlorate, are prepared by Mr Whiffen, of Battersea.
QUINICINE. An alkaloid obtained in 1853 by Pasteur, by exposing quinine or quinidine, under favorable circumstances, to a temperature varying from 248° to 266° Fahr., for several hours. It is very probable that this alkaloid is either identical, or in very close connection, with the amorphous alkaloid soluble in ether which occurs in all barks, and particularly in the young barks of the plantations in India.
QUINIDINE. C20H24O2N2.2Aq. Syn. Quinidia, Conchinine, &c. An alkaloid contained in many species of cinchona, together with quinine and cinchonine, and therefore often found in the mother liquors of quinine manufactures. It is identical with the β quinine of Van Heyningen, and was discovered, in 1833, by Henry and Delondre. As the cinchonidine discovered by Winckler, in 1848, has been unhappily denominated quinidine by this chemist, there is still a confusion about these alkaloids, and, therefore, the quinidine of commerce was very often a mixture of both, till Pasteur made, in 1853, a classical investigation of this matter. He maintained the name of quinidine for the alkaloid discovered by Henry and Delondre, because it is isomeric with quinine, and gives the same green colour when treated with chlorine followed by ammonia, and gave the name of cinchonidine to the alkaloid discovered by Winckler, because it is isomeric with cinchonine. He determined also the action of the solutions of these alkaloids on the plane of polarisation, and found that the quinidine turned this plane to the right, its molecular rotation in alcoholic solution being [a] = 250·75° →, whilst he found that the cinchonidine turned this plane to the left, its molecular rotation in alcoholic solution being [a] = 144·61° ←.
Prop. &c. Many of the salts of quinidine are very similar to those of quinine, but the normal salt with hydriodic acid is not only very different from that of quinine, but also from those of all the other cinchona-alkaloids. The normal hydriodate of quinidine is so very sparingly soluble in water that 1 part requires, at 60° Fahr., not less than 1200 parts of water to be dissolved. Therefore the presence of sulphate of quinidine in the sulphate of quinine, which often occurs, either from that article being carelessly made or from wilful adulteration, can be easily detected by adding a few minims of solution of iodide of potassium to the saturated solution of sulphate of quinine in water of 60° Fahr., whereby, if quinidine is present, its hydriodate will be separated either
in the shape of a sandy precipitate or, if only traces are present, in the shape of striæ on the sides of the glass where this has been rubbed by a glass rod.
For an account of its medicinal properties, the reader should consult the recent report from India upon the experiments made there by order of Government with all the four cinchona-alkaloids, which experiments are very favorable to the therapeutical action of quinidine compared with that of quinine.
QUININE. C10H12ON. Syn. Quina, Quinia. Till recently it was found in the greatest quantity in good Calisaya bark, particularly in that from Bolivia, but since it has been found in great quantity in some other barks, especially in the bark of Cinchona officinalis, for instance, in the bark of that species grown in Ceylon. Red bark contains not only quinine and cinchonine, but also cinchonidine.
Prep. 1. By precipitating a solution of sulphate of quinine with a slight excess of ammonia, potassa, or soda, and washing and drying the precipitate. By solution in alcohol, sp. gr. ·815, and spontaneous evaporation, it may be procured in crystals. Crystals may also be obtained from “its solution in hot water with a little ammonia.” (Liebig.)
2. (Direct.) By adding hydrate of lime, in slight excess, to a strong decoction of the ground bark made with water acidulated with sulphuric acid, washing the precipitate which ensues, and boiling it in alcohol; the solution, filtered while hot, deposits the alkaloid on cooling.
Prop., &c. Quinine, when prepared by precipitation, is an amorphous white powder, but when this precipitate is left in the liquor it assumes, after some time, the appearance of aggregated crystalline needles; when slowly crystallised from its solution, these needles are remarkably fine, and of a pearly or silky lustre. It is freely soluble in rectified spirit and in ether, and of all the cinchona-alkaloids it is the most soluble in ammonia. It is upon this fact that Kerner’s method for testing the purity of sulphate of quinine is founded. Its normal salts, if dissolved in water, have a slightly alkaline reaction upon red litmus paper. It is only sparingly soluble in water, even when boiling; both the fixed and volatile oils dissolve it with the aid of heat, more especially when it has been rendered anhydrous, or is presented to them under the form of an ethereal solution. It fuses by a gentle heat, without decomposition; forms crystallisable salts, which are only slightly soluble in water, unless it be acidulated, and, like the pure alkaloid, are extremely bitter, and possess much of the characteristic flavour of cinchona bark. It is precipitated by the alkalies and their carbonates, by tannic acid, and by most astringent substances.