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Show OFFICINAL GUAIACUM. 428 499 OFFICINAL GUAIACUM: bythe nitric, and pale blue by the oxymuriatic, but not by the acetic acid or alkalies. The solution in ether exhibits nearly the same properties. Guaiacumis soluble in about 15 parts of solu. tion of potass, and in 38 of ammonia; and the solutions are precipitated by the nitric, muriatic, anddiluted sulphuric acids. Sulphuric acid dissolves it, and nitric acid converts it into oxalic acid. Onbeing burnt, it leaves a large proportion of charcoal. Dr. Wollaston hasdiscovered a curious property of guaiacum. By exposureto air and light, it acquires a green colour. This effect is produced in the greatest degree by the most refrangible rays. In the least refrangible rays it is disoxidized, and the yellow colour is restored. The same effect is produced by hot metal. According to this analysis,it differs fromthe resins in the changes of colour produced onit byair andlight, and the action of the acids, in not forming tannin when treated with nitric acid, and in the large proportion of charcoal it affords when burnt. It is sometimes adulterated with colophony or common resin ; but the fraud is easily detected, by the smell of turpentine whichit emits when thrown on live coals. MEDICAL USE. Taken internally guaiacum commonlyexcites a sense of warmth in the stomach, a dryness of the m outh, with thirst. It increases the heat of the body, and quickens the circula tion. If the patient be : kept warm, it produces diaphoresis ; if exposed freely , 2 to the air, an increased flow of urine. gative. In large doses it is pur- Guaiacum is a useful remedy, 1. In rheumatism and gout. 2. In certain venereal symptoms ; as in foul indolent ulcers, and a thickened state of the ligaments or perio steum, remaining after the bodyis reduced by a mercurial course. Guaiacumwill| also suspend the progress of some of the secondary symptoms ; but it is totally incapable of eradicatin g the disease. 3. In cutaneous diseases, i 4. In ozena, and ser ofulous affec tions of the membranes and ligaments, The wood. is always exhibite d in decoction. Fromthe resinous nature of the active cons tituent of this subst: ance this cannot be a very active preparation, as the menstruum is totally incapable of dissolving, though it m ay suspend a little of the resin, The decoction of an ounce maybe drunk in cupfuls in the course of a day. The resin may be exhibited, 1. In substance, either madeintopills, or suspended in water in the form of an emulsion. In this way from 10 to 30 grains of the resin may be takenin the day. 2. In solution; in alcohol. About half an ounce of the tinc- ture, with three ounces of water, is a sudorific dose for an adult, if he attend to keeping himself warm. 3. Combined with an alkali. PREPARATIONS. Tincture or Guatacum. (Tinctura Guaiaci Officinalis. E.) Take of gum guaiacum, in powder, one pound; alcohol, two pounds and a half: Digest for ten days, and strain through paper. Tincrure or Guatacum. (Tinctura Guaiaci. D.) Take of guaiacum, four ounces ; rectified spirit of wine, two pints : Digest for seven days, andfilter. Whatis called gum guaiacum is in fact a resin, and perfectly soluble in alcohol. This solution is a powerful stimulating sudorific, and may be given in doses of about half an ounce in rheumatic and arthritic cases. It was once supposedto bea specific against the gout. Tincture or Guaracum. (Tinctura Guaiaci. L.) Take of guaiacum, in powder, four ounces; aromatic spirit of ammonia, a pint and a half: Digest for three days, andfilter. Ammoniatep Tincture or Guatacum. Ammoniata. E, D.) (Tinctura Guaiaci Take ofresin of guaiacum, in powder, four ounces; ammoniated alcohol, one pound and half (one pint and a half, D.): Digest for seven days,andfilter through paper. These are very elegant andefficacious tinctures; the ammoniated spirit readily dissolving the resin, and at the same time promoting its medicinal virtue. In rheumatic cases, a tea- oF |