CHAPTER XIX. SPIRITS OR ESSENCES. IN the Pharmacopoeia, the term "spiritus" is used to designate an alcoholic solution of volatile substances, chiefly volatile oils; in a few cases, water also is added. Of the twenty-five spirits recognized in the Pharmacopoeia, all but five can be conveniently prepared by the pharmacist, as they are quickly made and require only the ordinary apparatus usually found in the store; as a rule, they are prepared by simple solution of the liquid or gaseous body in alcohol, although sometimes distillation is resorted to. Whenever volatile oils are used in the preparation of spirits, only the very best should be selected, as the value of the finished product depends entirely upon the quality of the oil; particular attention should be paid to those oils likely to have assumed a terebinthinate odor, such as the oils of juniper, lemon, nutmeg, and orange peel. The following is a list of the official spirits, together with their composition: Official name. Spiritus Etheris Spiritus Etheris Compositus (Hoffman's Anodyne). Spiritus Etheris Nitrosi Spiritus Ammonia Spiritus Ammoniæ Aromaticus Composition. Ether 1 volume, Alcohol 3 volumes. Ethereal Oil 1 volume, Ether 13 volumes An alcoholic solution of Ethyl Nitrite, con- An alcoholic solution of Ammonia containing 10 per cent. by weight of the gas. A hydro-alcoholic solution of normal Ammonium Carbonate, containing 70 per cent. by volume of Alcohol, 1 per cent. of Oil of Lemon, and per cent. each of Oil of Nutmeg and Oil of Lavender Flowers Spiritus Amygdala Amaræ (Es- Oil of Bitter Almond 1 volume, Alcohol 80 sence of Bitter Almond). Spiritus Anisi Spiritus Aurantii . Spiritus Aurantii Compositus Spiritus Camphora volumes, and Distilled Water sufficient to make 100 volumes Oil of Anise 1 volume, Deodorized Alcohol 9 volumes. Oil of Orange Peel 1 volume, Deodorized Alcohol 19 volumes Oil of Orange Peel 20 volumes, Oil of Lemon 5 volumes, Oil of Coriander 2 volumes, Oil of Anise volume, Deodorized Alcohol 72} volumes. Camphor 10 Gm., Alcohol sufficient to make Chloroform 6 volumes, Alcohol 94 volumes. Spiritus Frumenti (Whiskey) An alcoholic liquid obtained by the distillation of the mash of fermented grain (usually of mixtures of corn, wheat, and rye), and at least two years old. Oil of Gaultheria 1 volume, Alcohol 19 volumes Spiritus Glonoini (Spirit of Nitro- An alcoholic solution of Glonoin, or Nitrogly Spiritus Gaultheria glycerin). Spiritus Juniperi Spiritus Juniperi Compositus Spiritus Lavandulæ Spiritus Limonis (Essence of cerin, containing 1 per cent. by weight of the substance. Oil of Juniper 1 volume, Alcohol 19 volumes. Oil of Juniper 8 volumes, Oil of Caraway and Oil of Fennel each 1 volume, Alcohol 1400 volumes, Water sufficient to make 2000 vols. Oil of Lavender Flowers 1 volume, Deodorized Alcohol 19 volumes A 5 per cent. alcoholic solution of Oil of Lemon; this spirit also contains in each liter the oil and coloring matter from 50 Gm of freshly grated lemon peel. Spiritus Mentha Piperita (Essence Oil of Peppermint 1 volume, Alcohol 9 vols ; of Peppermint). this spirit is colored green by peppermint herb. Spiritus Menthæ Viridis (Essence Oil of Spearmint 1 volume, Alcohol 9 volumes; of Spearmint). this spirit is colored green by spearmint herb Oil of Myrcia 16 volumes, Oil of Orange Peel 1 volume, Oil of Pimenta 1 volume Alcohol 1220 volumes, Water sufficient to make 2000 volumes. Oil of Nutmeg 1 volume, Alcohol 19 volumes. A solution of Phosphorus in Absolute Alcohol representing 0.0012 Gm. in each Cc. An alcoholic liquid obtained by the distillation of the fermented unmodified juice of fresh grapes, and at least 4 years old. Special Remarks on Some Official Spirits. Spiritus Etheris Compositus. Commercial Hoffmann's anodyne varies greatly in composition, and is probably never identical with the official spirit-in fact, manufacturers do not claim this to be the case; hence the necessity for discrimination between the two preparations when physicians prescribe compound spirit of ether. The commercial varieties of Hoffmann's anodyne are often obtained as by-products in the rectification of ether, and consist of mixtures of heavy and light oil of wine, ether, alcohol, and water, brought up to a certain arbitrary standard, varying with different manufacturers. Spirit Etheris Nitrosi. This preparation is a very unstable solution, at least as far as the proportion of active ingredients is concerned ; even under the most favorable conditions it deteriorates; to retard this change, as far as possible, the spirit should be preserved in small, well-stoppered bottles, in a cool, dark place. Spirit of nitrous ether should be purchased in original packages, and never in bulk drawn from carboys. The chemical reactions involved in the manufacture of this spirit will be explained elsewhere, as also the official method of determining its quality. Spiritus Ammonia. The object of directing the use of alcohol recently distilled and preserved in glass, is to avoid discoloration of the liquid, which is apt to occur if ammonia gas be dissolved in alcohol kept in barrels and containing organic impurities. Spirit of ammonia is of the same strength as official ammonia water, and is intended to be used in cases where the aqueous solution is inadmissible. Spiritus Ammonia Aromaticus. Ammonia water is used in connection with official ammonium carbonate, for the purpose of converting the latter into the normal salt, as this alone is soluble in the alcoholic liquid; in order to complete the change, it is advisable to let the aqueous solution stand for twelve or twenty-four hours, before adding it to the mixture of oils and alcohol. Aromatic spirit of ammonia is of faint color when freshly prepared, but gradually becomes darker. Spiritus Frumenti. Whiskey, as recognized by the Pharmacopoeia, should contain from 50 to 58 per cent. by volume of alcohol, which is readily ascertained by aid of the alcoholometer described on page 57. 100 Cc. of whiskey, when evaporated to dryness, should not yield more than 0.25 Gm. of residue." Spiritus Phosphori. The weighing of phosphorus requires considerable care, owing to its very inflammable nature; it should always be performed in water, and the phosphorus rapidly dried by means of filter-paper, before it is introduced into the absolute alcohol. The use of an upright condenser is necessary when heat is employed, to avoid ignition and loss of alcohol, which would occur in an unstoppered flask; agitation with cold absolute alcohol will also dissolve phosphorus, but it is a tedious process. Phosphorus is far more soluble in fixed oils or chloroform, but since spirit of phosphorus is used chiefly in the preparation of elixir of phosphorus, such solutions would be inadmissible. Phosphorus is rapidly oxidized upon exposure to air, and particularly when in solution, hence the spirit must be preserved in small, securely stoppered vials, in a cool, dark place. Spiritus Vini Gallici. Official brandy should be at least four years old, and contain from 46 to 55 per cent. by volume of alcohol; the older the brandy the finer is its quality. 100 Cc. of brandy, upon evaporation to dryness, should not yield more than 1.5 Gm. of residue. CHAPTER XX. TINCTURES. TINCTURE is the name applied to solutions of non-volatile or only partially volatile substances, in liquids other than simple water or glycerin, and which invariably contain alcohol; solutions of volatile substances in alcohol are always termed spirits or essences. While tinctures are usually assumed to be solutions of vegetable principles, this is not the case in all the official tinctures; two of these, the tinctures of iodine and ferric chloride, are solutions of inorganic substances. Tincture of iodine is also an exception to the rule that tinctures are solutions of non-volatile substances. The men struum or solvent used in the preparation of tinctures may be simply alcohol, various mixtures of alcohol and water, or of alcohol, glycerin, and water, ammoniated alcohol in the form of aromatic spirit of ammonia, and mixtures of alcohol and ether; according as these different menstrua are employed, tinctures are divided into groups designated as alcoholic, hydro-alcoholic, ammoniated, and ethereal tinctures respectively. Ethereal tinctures are not recognized in our Pharmacopoeia, but are employed to some extent in Europe. The Pharmacopoeia recognizes seventy-two tinctures, of which twenty are made with alcohol alone, fifty with a hydro-alcoholic menstruum, and two with ammoniated alcohol; from this it is seen that the tendency is in the direction of weaker alcohol, and many tinctures formerly made with alcohol exclusively, are now found equally efficient and permanent when made with a mixture of alcohol and water. The valuable solvent and preservative properties of alcohol have been explained in a former chapter; these are retained in the various hydro-alcoholic mixtures, in which the proportions of alcohol and water are so adjusted that complete extraction of the valuable constituents of the drug is insured as well as permanence of the solution; the solution of much inert and unstable matter is likewise thus avoided. Tinctures made with weak alcohol are also more readily miscible with aqueous liquids-a point often of great value in dispensing medicines. The addition of glycerin to the menstruum is frequently desirable to facilitate the perfect extraction of astringent and other principles and prevent subsequent changes in the finished tincture, due to atmospheric influences, which cause the gelatinization of the solution or deposit of unsightly precipitates. Tinctures are, as a rule, prepared by percolation, except in the case of a few resins, balsams, gum-resins, and extractive drugs, for which maceration has proven more satisfactory. The process of per colation has been fully described on page 124 et seq., as well as the precautions necessary to insure perfect extraction of drugs. The great advantages to be derived from a proper moistening and preliminary maceration of the drug have been already pointed out in the chapter on Percolation. The value of this mode of solution cannot be overestimated in the preparation of tinctures, and as the amount of available menstruum is ample, complete exhaustion of the drug will have been effected before all the solvent has passed through; the objection urged that menstruum is retained by the mare, can be easily overcome (see page 129), and is but trifling as compared with the gain in time and in the perfect, clear solution at once obtained. Of the seventy-two official tinctures, fifty-six, or over three-fourths of the whole number, are directed to be made by percolation, eleven by maceration, four by direct solution, and one by decoction and subsequent concentration. In the pharmacopoeial titles of tinctures, the names of the drugs furnishing the active ingredients are indicated in all but twelve; of these, six are officially designated as compound tinctures, namely: the compound tinctures of benzoin, cardamom, catechu, cinchona, gentian, and lavender. In the remaining six titles, only the name of the chief ingredient is mentioned; as tincture of aloes, tincture of cinnamon, camphorated tincture of opium, tincture of rhubarb, sweet tincture of rhubarb, and aromatic tincture of rhubarb. Upon exposure to air and light, tinctures, like all vegetable solutions, are apt to undergo change, and should, therefore, be kept in well-closed containers, in shady places; extremes of temperature are equally hurtful on account of the possible change in the menstruum. Fortunately, the deposits formed in tinctures consist, as a rule, only of inert extractive matter, which may be removed by filtration. The following table shows at a glance the composition and strength of the official tinctures, as well as the fineness of powder and the menstruum used in their preparation. |