SOURCE. (1) Make a strong decoction of willow bark. (2) Remove the tannic acid by warming and agitating the decoction with Lead Oxide. (3) Evaporate the solution. Salicin crystallizes out, and is purified by repeated solution, and crystallization. CHARACTERS.-Colorless, silky, shining crystalline needles, rhombic prisms, or a white crystalline powder, odorless, and having a very bitter taste. Solubility. In 21 parts of water, and in 71 parts of Alcohol; insoluble in Ether or Chloroform. IMPURITY. Alkaloids. Dose, 1 gm.; 15 gr. ACIDUM SALICYLICUM. SALICYLIC ACID.-HC,H,O1 = 137.01. A monobasic organic acid [CH(OH)COOH], existing naturally, in combination, in various plants, (see Oleum Gaultheria and Oleum Betula), but generally prepared synthetically from Phenol. SOURCE.-Made by combining Sodium Carbolate with Carbon Dioxide Gas. Thus, dry Carbon Dioxide is passed through Sodium Carbolate heated to 428° F.; 220° C. 2NaCHO + CO2 = Na2C,H,O, (Sodium Salicylate), +CH ̧O (Phenol). This is treated with Hydrochloric Acid. Na2C,H,O3 + 2HCl = 2NaCl + HC,H,O, (Salicylic Acid). CHARACTERS.-Light, fine, white, prismatic needles, or a light, white, crystalline powder; odorless, or having a slight gaultheria-like odor, with a sweetish, afterwards acrid taste, and permanent in the air. Solubility. In 308 parts of water and 14 of boiling water; in 2 parts of Alcohol; very soluble in boiling Alcohol; also soluble in Ether, Absolute Alcohol and Chloroform. Resembling Artificial Salicylic Acid.— Strychnine, but the crystals of Strychnine are larger, colorless, non-irritating, less soluble, and the solution is very bitter. IMPURITIES. Orthocreosotic, metacreosotic, and paracreosotic acids, only in artificial salicylic acid. In the best specimens they are absent. Other impurities: iron, phenol, hydrochloric acid, and coloring matter. INCOMPATIBLES.-Spirit of Nitrous Ether; iron salts; lead acetate; potassium iodide; quinine salts; exalgin; urethane. Dose, 0.500 gm. (500 milligm.); 71⁄2 gr. = SODII SALICYLAS.-Sodium Salicylate. NaC,H,O, 158.89. It should contain not less than 99.5 per cent. of pure Sodium Salicylate [CH,(OH)COONa], and should be kept in well-stoppered bottles, protected from light. SOURCE. Obtained by acting on Sodium Carbonate with Salicylic Acid. 2HC,H ̧О ̧ + Na2CO ̧= 2NaC,H,O3 + H2O + CO2. The solution may be strained through muslin and heated to expel the Carbon Dioxide. CHARACTERS.-White, micro-crystalline powder or scales, or an amorphous, colorless powder, or having not more than a faint pink tinge; odorless and having a sweetish, saline taste, Solubility. In 0.8 part of water, and in 5.5 parts of Alcohol; very soluble in boiling water or Alcohol; also soluble in Glycerin. INCOMPATIBLES.-Hydrobromic acid, for sodium bromide is formed and salicylic acid is precipitated; Spirit of Nitrous Ether, ferric salts, mineral acids, quinine salts in solution, lime water, lead acetate, silver nitrate (in solution), and sodium phosphate (in powder). Dose, 1 gm.; 15 gr. LITHII SALICYLAS.-Lithium Salicylate. LiC,H,O,= 142.99. It should contain not less than 98 per cent. of pure Lithium Salicylate, CH(OH) COOLi. SOURCE. Obtained by heating Salicylic Acid, Lithium Carbonate, and Water, until the effervescence ceases, filtering and evaporating. Li2CO, + 2HC,H2O2 = 2LiC,H¿O, + H2O + CO2. CHARACTERS.-A white, or grayish-white powder, odorless, and having a sweetish taste; deliquescent on exposure to air. Solubility.-Very soluble in Water and in Alcohol. Dose, 1 gm.; 15 gr. AMMONII SALICYLAS.-Ammonium Salicylate. NH,C,H2O1= 153.94. It should contain not less than 98 per cent. of pure Ammonium Salicylate [CH、(OH)COONH1], and should be kept in well-stoppered bottles, protected from heat and light. SOURCE. Obtained by neutralizing Salicylic Acid with Ammonium Carbonate, filtering, evaporating and allowing to crystallize. CHARACTERS.-Colorless, lustrous, monoclinic prisms, or plates, or a white, crystalline powder, odorless, and having at first a slightly saline, bitter taste, with a sweetish taste afterward. Solubility.-In 0.9 part of water and 2.3 parts of Alcohol; freely in boiling water and in 1 part of boiling Alcohol. Dose, 0.250 gm. (250 milligm.); 4 gr. For Bismuthi Subsalicylas see p. 164. STRONTII SALICYLAS.-Strontium Salicylate. Sr(C,H2O3)2 + 2H2O = 394.72. A white, crystalline powder, which should contain not less than 98.5 per cent. of pure Strontium Salicylate. Dose, 1 gm.; 15 gr. ACTION. Antiseptic; irritant; strongly cholagogue; antipyretic; dia phoretic; diuretic (markedly increasing the excretion of uric acid). In exceptional instances skin eruptions are caused, and in some individuals a train of symptoms analogous to those of cinchonism, and designated as salicylism, results from the use of salicylic preparations. USES. Externally, as antiseptic and stimulating applications and for the checking of abnormal perspiration; also in parasitic and other skin diseases. Internally, rheumatic fever (in which these drugs seem to act as specifics); gout; migraine; sciatica; diabetes; cholelithiasis. Salicin, which produces no gastric irritation, is useful in atonic dyspepsia, as a stomachic, and also in gastro-intestinal catarrh and the chronic diarrhoea of children. Synonym.-Salol. PHENYLIS SALICYLAS (Salol, U. S. P., 1890). PHENYL SALICYLATE.—C13H10O3 =212.47. The Salicylic Ester [CH,(OH)COOCH ̧1:2] of Phenyl. SOURCE. By heating Salicylic Acid with Phenol in the presence of Phosphorus Pentachloride; this action dehydrates and withdraws the elements of water, and unites the Phenyl group with the Salicylic Acid radical. CHARACTERS.-A white, crystalline powder, having a faintly aromatic odor, and a slight, but characteristic, taste. Permanent in the air. Solubility. In 2333 parts of water and in 5 parts of Alcohol; very soluble in hot Alcohol, Ether, Chloroform, and fixed or volatile oils. IMPURITIES. Sulphates, chlorides and free acids. INCOMPATIBLES.-Camphor, phenol, chloral, naphthalene, thymol and ferric chloride. Dose, 0.500 gm. (500 milligm.); 71⁄2 gr. ACTION. Antiseptic; germicidal; antipyretic; its too free use may give rise to the symptoms of carbolic acid poisoning. USES. Externally, for wounds, burns, ulcers, etc., and for erysipelas, impetigo and other cutaneous affections; internally as an intestinal antiseptic in acute diarrhoea, dysentery, typhoid fever, cholera and other diseases; epidemic influenza; neuralgias and the bilious form of sick headache. Unofficial Preparations. SALOPHENUM. Salophen.-CH‚(OH)CO2C,H,NHCOCH, 270.40. Synonym. -Acetylparamidophenol Salicylate. SOURCE. From Paranitrophenol Salicylate by a complicated process, and purifying by crystallization from Alcohol. CHARACTERS.-Minute white scales, free from odor or taste. It contains 50.9 per cent. of Salicylic Acid. Solubility.-Almost insoluble in water; freely soluble in Alkalies, Alcohol and Ether. Dose, .30 to 1.00 gm.; 5 to 15 gr. ACTION. It is regarded as possessing the medicinal, without the toxic, qualities of salol. USES. As a substitute for salicylic acid in acute rheumatism and as an intestinal antiseptic. ASPIRINUM. Aspirin. Synonyms.-Acidum Aceto-salicylicum. Acetyl Salicylic Acid. It is derived from the action of Acetic Anhydride upon Salicylic Acid. Colorless crystalline needles of an agreeable, somewhat acid taste, soluble in water, I per cent. Used in rheumatism, gout, etc., and as an analgesic in neuralgia and dysmenorrhoea. It is considered by many preferable to the salicylates. Dose, 1 to 4 gm.; 15 to 60 gr. SALOL CAMPHORATUM. Camphorated Salol. Synonym.-Salol Camphor. A liquid insoluble in water, but miscible with fixed and volatile oils, ether and alcohol, which is prepared by rubbing three parts of Salol with two parts of Camphor, and then gently heating. Used as a local anesthetic. OLEUM BETULÆ (Oleum Betulæ Volatile, U. S. P., 1890). OIL OF BETULA. Synonym.-Oil of Sweet Birch. A volatile oil obtained by distillation from the bark of Betula lenta Linné (Sweet Birch); (Fam. Betulacea). Habitat.-Northern United States. It is identical with Methyl Salicylate (CH,C,H2O2 = 150.92), and nearly identical with Oil of Gaultheria. CHARACTERS. It is optically inactive, but otherwise has essentially the same properties and conforms to the same reactions and tests as Oleum Gaultheriæ. QUERCUS.-White Oak. The dried bark of the Quercus alba Linné (Fam. Cupuliferæ). Habitat.-North America, westward to Minnesota, Kansas, and Mississippi; in woods. CHARACTERS.-In nearly flat pieces, 2 to 10 mm. thick; externally light brown, becoming darker with age, rough-fibrous; fracture uneven, |