of quinine. It is colourless; has a bitter, acrid, and somewhat metallic taste; dissolves in 200 parts (300 parts—Thomson) of cold and 50 to 54 parts of boiling water, in 11⁄2 parts of cold alcohol, and in 25 parts of cold, and 6 parts of boiling ether; it has an alkaline reaction, fuses at about 194° Fahr., is slightly volatile at common temperatures, and freely rises in vapour at 212° Fahr.; at higher temperatures it volatilises with partial decomposition; with the acids it forms salts, of which several are crystallisable.
Tests.—1. Nitric acid forms with it a yellow solution:—2. With cold sulphuric acid it gives a colourless solution, which becomes red only when heated:—3. Aqueous solutions of atropia and its salts are—a, turned red by tincture of iodine—b, gives a citron-yellow precipitate with terchloride of gold—c, a flocculent whitish precipitate with tincture of galls, and—d, a yellowish-white one with bichloride of platinum:—4. Heated with caustic potassa or soda, it suffers decomposition, and ammonia is evolved:—5. A weak solution cautiously applied to the eyelid or conjunctiva, produces dilation of the pupil lasting for several hours.
Pur., &c. Alkaloid prepared from the root of atropa belladonna. Crystals; white, in the form of prisms; soluble in water and rectified spirit. It leaves no ash when burned with free access of air (B. P.).
Phys. eff. It is a very powerful narcotico-acrid poison.[103] Its effects are similar to those of belladonna, but considerably more powerful. “A very minute (imponderable) quantity applied to the eye is sufficient to dilate the pupil.” (Pereira.) The 1⁄12 to 1⁄10 gr. often causes very serious effects in the human subject. The 1⁄6th of a grain accelerates the pulse, affects the brain, causes dryness of the throat, difficulty of deglutition, dilation of the pupil, dimness of sight, giddiness, strangury, numbness of limbs, sense of formication in the arms, rigidity of thighs, depression of pulse, and sometimes feebleness or loss of voice. These symptoms continue for from 12 to 24 hours. In larger doses death ensues.
[103] A “cerebro-spinal poison.”—Taylor.
Ant., &c. These may be similar to those described under Belladonna and Alkaloid.
Uses. Chiefly as an external agent, as a substitute for belladonna, to cause dilation of the pupil; and as a local anæsthetic or anodyne, especially in facial neuralgia. Internally, it has been occasionally given in hooping-cough, chorea, and a few other nervous diseases.—Dose, 1⁄30 gr., gradually increased to 1⁄20, or, occasionally, even 1⁄15 gr. in solution, or made into a pill with liquorice powder and honey, or syrup, or used endermically; for a collyrium, 1 gr. to water 1 oz., a few drops only being applied to the eye at a time, the greatest caution in each case being observed. It is also employed to make the sulphate. In dispensing it a single drop of acetic acid, or dilute sulphuric acid, will be found to facilitate and ensure its perfect solution. See Belladonna and Belladonine.
Atropia, Sul′phate of. Syn. Atro′pia sul′phas, L. Prep. (B. P.) Take of atropia, 120 gr.; distilled water, 4 fl. dr.; diluted sulphuric acid, a sufficiency.
Mix the atropia with the water and add the acid gradually, stirring them together until the alkaloid is dissolved and the solution is neutral. Evaporate it to dryness at a temperature not exceeding 100°.
Characters and Tests.—A colourless powder, soluble in water, forming a solution which is neutral to test-paper, and when applied to the eye dilates the pupil as the solution of atropia does. It leaves no ash when burned with free access of air.