Chapter M: M. Pelletier and Caventou have discovered in this substance, a (2)

QUALITIES. _Form_, irregular masses resembling lumps of sugar, being an aggregation of acicular four-sided prisms terminated by dihedral summits, which are slightly efflorescent; by careful crystallization, it may be obtained in quadrangular prisms. _Taste_, sweet and astringent. CHEMICAL COMPOSITION. Although it has been termed a _Super_-acetate, it appears to be a neutral salt, and that its power of reddening valuable blues is attributable to a partial decomposition; for when dissolved in water containing the least portion of carbonic acid, a white carbonate of lead is precipitated, and a corresponding portion of acetic acid is necessarily disengaged. The College have therefore now designated it as an _acetate_. According to the experiments of Berzelius, this salt, in its anhydrous state, consists of one proportional of acetic acid, and one proportional of oxide of lead; so that the proportion of the metallic base is one-third of that in the _sub_-acetate. SOLUBILITY. It is dissolved in 25 parts of water, hot or cold; it is also soluble in alcohol. When common water is employed the solution is quite turbid, unless a small proportion of acetic acid be previously added. INCOMPATIBLE SUBSTANCES. _The alkalies, alkaline earths and their carbonates_; _most of the acids_; _alum_; _borax_; the _sulphates, and muriates_; _soaps_; _all sulphurets_; _ammoniated, and tartarized iron_; _tartarized antimony_; _undistilled water_. The solution of _acetate of ammonia_ decomposes that of this salt, in consequence of the carbonic acid which is generally diffused through it. It has lately been discovered that _Gallic acid_ and _Tannin_ are capable of combining with lead in solution, and of forming a perfectly insoluble substance, which falls to the bottom of the vessel; hence all vegetable astringents must be considered as incompatible with this medicine. On this account, liquors which have been kept in oak casks,[603] for a certain time, must be freed from lead. This explains a fact, with respect to the effect of new rum in the West Indies, of some importance. This spirit, when newly distilled, is found to contain traces of lead, derived from the leaden rims of the coppers, and the leaden worm, used for its condensation; but, by being kept about twelve months in oaken casks, it loses its deleterious properties, and no longer exhibits any traces of this metal.[604] Certain bodies appear likewise to be incompatible with the compounds of lead, not from the _chemical_ changes they induce, but from the contrary effects they produce upon the body; thus mercury appears to invalidate their powers and to counteract their effects, as we may have observed in treating saturnine cholic. I suspect also that antimony operates in the same manner; M. Merat relates the case of an apothecary who was cured of a desperate saturnine cholic, after having taken, in the course of eight days, eighty grains of tartarized antimony. MED. USES. I feel no hesitation in pronouncing this salt of lead to be one of the most valuable resources of physic; from the results of numerous cases, I state with confidence that it is more efficient in stopping pulmonary and uterine hemorrhage, than any other known remedy—“_nil simile, nec secundum_,”—and that its application is equally safe and manageable; but it must not be combined with substances capable of decomposing it, nor must it be simultaneously administered with the medicines which are frequently prescribed in conjunction with it, as an _Infusion of Roses_, _Sulphate of Magnesia_, &c. Alum has also been in some cases added to it, with the intention of increasing its astringency. It is evident that under such circumstances an insoluble and inert _Sulphate of Lead_ will be produced. The experiments of Orfila confirm the truth of these views, and shew that such substances act as counter-poisons for the salts of lead. According to my experience, those vegetable acids which decompose the acetate of lead, and form insoluble salts with its base, are not _medically_ incompatible, when administered simultaneously with it, although no scientific physician would prescribe such a mixture; this fact is shewn by the circumstance of potations, containing malic and tartaric[605] acids, not having been found to invalidate the efficacy of this salt. Whether the stomach in the first instance prevents the decomposition, and its necessary results, or allows the operation of the usual affinities, and then subsequently decomposes the insoluble compound which results from them, by the abstraction and _digestion_ of its vegetable constituent, are questions for future inquiry, when the laws of gastric chemistry shall be better understood, and more justly appreciated. I have also seen much benefit accrue from this medicine in protracted diarrhœa, when it has checked the bowels more effectually even than opium. M. Gaspard has communicated to the public, through the medium of _Majendie’s Journal de Physiologie_, (3 numéro Juillet, 1821,) a paper upon the operation of _Acetate of Lead_, entitled “_Experiences Physiologiques et Medicales sur L’Acetate de Plomb_,” in which he asserts that this metallic salt cannot be administered without risk in any dose, unless indeed it be given in vehicles which decompose it, and which, he adds, appears generally to have happened in the prescriptions of those who have given it extensively. He observes, that “it produces a slow and peculiar inflammation of the bowels, as well as of the lungs; and that it, moreover, occasions _Cholica Pictonum_.” No one, I apprehend, will deny the poisonous quality of acetate of lead, any more than that of arsenic; and yet both may, by proper management, be rendered therapeutical agents of value and safety. FORMS OF EXHIBITION. In that of pill, guarded by opium; it will be prudent to recommend an abstinence from all potation, except that of cold water, or draughts, composed of diluted acetic acid, for at least an hour after the ingestion of the pill.[606] DOSE, gr. ½ to gr. j. _Form. 57._ OFFICINAL PREP. _Cerat. Plumb. acetat_. L.[607]

PODOPHYLLUM PELTATUM.

_May Apple._ _Radix._

[This plant is found in almost every part of the United States in low and moist situations. It flowers in May and June, and the root is the only part used in medicine. By analysis this is found to contain resin, bitter extractive, fœcula, and a slight proportion of a gummy substance. The root of the May Apple is an excellent active cathartic, operating in a manner very similar to the common Julap. It is given in powder, in doses of about grs. xx. The proper period for collecting the root for medicinal purposes is the autumn, when the leaves of the plant have turned yellow. It should be carefully dried and then pulverized.]

POTASSA CUM CALCE. L.E.

KALI CAUSTICUM CUM CALCE. D.

The addition of lime to potass renders it less deliquescent, and more manageable, as an escharotic.

POTASSA FUSA. L.

POTASSA. E. KALI CAUSTICUM. D.

_Lapis infernalis_. P.L. 1720.

QUALITIES. _Form_, a white brittle substance, extremely caustic and deliquescent, and possessing in an eminent degree all the properties denominated _alkaline_. SOLUBILITY. f℥j of water dissolves ʒvij; it is also soluble in alcohol. CHEMICAL COMPOSITION. This preparation, independent of its impurities, is the _hydrated protoxide of potassium_, although in the state in which it is cast into sticks it generally contains a little _Peroxide_,[608] and therefore evolves oxygen when dissolved in water. MED. USES. It is a most powerful caustic (_causticum commune acerrimum_), and is frequently employed to establish an ulcer; or, instead of incision, to open a tumour. It has the advantage of other caustics, from the circumstance of our being able to neutralize its powers by touching it with vinegar, and thus to arrest its progress in an instant; it is however more liable to produce a large eschar than nitrate of silver, in consequence of the chemical action of the alkali upon the skin. Within the last few years, surgeons have greatly preferred the use of this caustic to that of _nitrate of silver_, in cases of organic stricture of the urethra, as acting more powerfully, and yet occasioning less irritation than the latter substance; it is also said that the part which it destroys is sooner detached and more easily eliminated. Its disposition, however, to extend its sphere of action has occasioned such a destruction of the membrane as to allow the urine to pass into the cellular substance, by which very serious effects have been produced. For this reason there are cases in which the _nitrate of silver_ is still to be preferred. As an internal remedy it is only employed in solution. See _Liquor Potassæ_.[609]

POTASSÆ ACETAS. L. ACETAS POTASSÆ. E.

ACETAS KALI. D. _Kali Acetatum._ P.L. 1787.—_Sal diureticus._ P.L. 1745.—_Terra foliata Tartari._—_Sal Sennerti._—_Magisterium Purgans Tartari._—_Sal Essentiale vini._ _Oleum Tartari Sennerti._—_Sal digestivus Sylvii, &c._

QUALITIES. _Form_, masses of a foliated, laminar texture, extremely deliquescent; _Odour_, slight and peculiar; _Taste_, sharp and pungent. SOLUBILITY. f℥j of distilled water at 60° dissolves 404 grains, or 100 parts of it are soluble in 105 parts of water; the solution soon undergoes spontaneous decomposition; it is soluble in four times its weight of alcohol.—CHEMICAL COMPOSITION. It consists of one proportional of each of its components, or 48 potass and 50 acetic acid. INCOMPATIBLE SUBSTANCES. It is decomposed by _tamarinds_ and _most sub-acid fruits_; by almost every acid, as well as every variety of neutral salt, whether _alkaline_, _acid_, or _metallic_. MED. USES. In small doses, diuretic; in larger ones, mildly cathartic. Dose, ℈j to ʒj to produce the former, ʒij to ʒiij to excite the latter of these effects. FORMS OF EXHIBITION. On account of its deliquescent property it is not admissible in powders or pills, but should be always exhibited in solution. (_Form. 108, 110, 111._) In the former editions of this work, I introduced under the present article, those views regarding the operation of saline bodies upon the kidneys, and their decomposition by the digestive organs, which I considered as capable of throwing some light upon the medicinal operation of these bodies. Having, however, in the present edition of my work devoted a chapter to the consideration of Diuretics, I have necessarily removed all my general observations upon this subject to that part of the work; I therefore entreat the reader to refer to the first part, page 93. Alibert, in speaking of the diuretic virtues of this salt, says that it is so well suited to the sensibility of the Absorbents that its administration is frequently followed by very salutary effects. (_Elémens de Thérapeutique_, _vol._ i. _p. 327_.)

ADULTERATIONS. _Tartrate of potass_ is discovered by adding a solution of tartaric acid, which will occasion with it a copious precipitate; the _sulphates_, by their forming with acetate of lead, or muriate of baryta, precipitates insoluble in acetic or muriatic acid. The brown tinge which it frequently exhibits depends upon the same cause as that which usually imparts colour to the _Liquor. Ammon. Acet._ This salt is also sometimes contaminated with _lead_, which arises from its having been prepared by decomposing the _acetate of lead_ by means of _carbonate of potass_.

POTASSÆ CARBONAS. L.E.

_Carbonate of Potass._

QUALITIES. _Form_, crystals which are four-sided prisms with dihedral summits, permanent in the air; _Taste_, slightly alkaline without acrimony. CHEMICAL COMPOSITION. It is a _bi-carbonate_, consisting of two proportionals of carbonic acid and one proportional of potass; and in its crystalline form, it also contains water equal to one proportional. SOLUBILITY. It is soluble in 4 parts of cold, and in ⅚ths of its weight of boiling water, in which it is partially decomposed, carbonic acid being emitted during the solution; it is quite insoluble in alcohol. MED. USES. In cases where an alkali is indicated, this preparation offers an agreeable and efficient remedy; and experience has shewn that its additional proportion of carbonic acid does not in the least invalidate its alkaline agency. In disordered states of the digestive functions, alkalies frequently act with surprising effect; in calculous affections their value has been already noticed (see _Liquor Potassæ_), and the stomach appears to bear the protracted exhibition of the carbonate of potass or soda, with more temper than it does that of any other alkaline combination; and on account of the increased quantity of carbonic acid which this salt contains, it is preferable for effervescing draughts. (See _Acid. Citric._ and _Form. 123, 168_.) INCOMPATIBLE SUBSTANCES. _Acids_ and _acidulous salts_; _borax_; _muriate of ammonia_; _acetate of ammonia_; _alum_; _sulphate of magnesia_; _lime water_; _nitrate of silver_; _ammoniated copper_; _muriate of iron_; _sub-muriate and oxy-muriate of mercury_; _acetate of lead_; _tartarized antimony_; _tartarized iron_; _the sulphates of zinc_, _copper_, _iron_, &c. DOSE, grs. x to ʒss.

POTASSÆ NITRAS. L.E. NITRUM. D.

_Nitre_ or _Salt Petre_.

QUALITIES. _Form_, crystals which are six-sided prisms usually terminated by dihedral summits. _Taste_, bitter and sharp with a sensation of cold. CHEMICAL COMPOSITION. It consists of one proportional of nitric acid, and one proportional of potass. SOLUBILITY. It dissolves in seven parts of water at 60°, and in its own weight at 212°. Its solubility is considerably increased by adding muriate of soda to the water; its solution is attended with a great reduction of temperature; it is quite insoluble in alcohol. INCOMPATIBLE SUBSTANCES. _Alum_; _sulphate of magnesia_; _sulphuric acid_; _the sulphates of zinc, copper, and iron_; according to the usual laws of affinity, it should be also decomposed by _sulphate of soda_; this however only takes place at the temperature of 32°, and then but partially. MED. USES. Refrigerant, in which case the draught should be swallowed immediately after the solution of the salt is complete, for if it be allowed to stand for some time, its effect with regard to cooling is not nearly so evident (see _Form. 138, 144_); as a diuretic, its powers are too inconsiderable to be employed, except in combination (_Form. 102, 109, 115, 170_); a solution of ʒj to f℥vj of rose water forms a good detergent gargle, and a small portion allowed to dissolve slowly in the mouth, will frequently remove an incipient inflammation of the tonsils: for its _modus operandi_ as a diuretic, see _Potassæ Acetas_. DOSE, grs. x to xv, as a diuretic or refrigerant; grs. xxv to xl are aperient, and in large doses it excites vomiting, bloody stools, convulsions, and even death. The best antidotes are opium and aromatics. IMPURITIES. As it occurs from the hand of nature it is far from pure, and even by art it is freed with difficulty from sea salt; the presence and quantity of which in any specimen, may be learnt by adding nitrate of silver to its solution as long as any precipitate is produced.

POTASSÆ SUB-CARBONAS. L.E.

SUB-CARBONAS KALI. E.

_Kali Præparatum_, P.L. 1787. _Sal Absinthii._

_Sal Tartari._ 1745.

Before the nature of this salt was well understood, it received various appellations according to the different methods by which it was procured, and it was supposed to possess as many different virtues, as _Salt of Wormwood_, _Salt of Tartar_, _Salt of Bean Stalks_, &c.

QUALITIES. _Form_, coarse white grains, so deliquescent, that by exposure to air they form a dense solution, (_Oleum Tartari per deliquium_, P.L. 1720.) _Taste_, alkaline and urinous.[610] CHEMICAL COMPOSITION. This salt, although far from being pure, is sufficiently so for every pharmaceutical purpose. It consists of one proportional of acid and one proportional of potass, with variable quantities of _sulphate of potass_, _muriate of potass_, _siliceous earth_, _alumina_, together with the _oxides of iron_, and _manganese_. SOLUBILITY. It is dissolved by twice its weight of water; the residue, if any, may be considered as impurity; it is insoluble in alcohol; with oils it combines, and forms soaps. INCOMPATIBLE SUBSTANCES. They are enumerated under _Potassæ Carbonas_. MED. USES. Antacid, and diuretic, (_Form. 101, 107, 129_), but it is far less pleasant than the carbonate; it is principally used for making saline draughts, see _Acid. Citric._ and _Form. 107_. DOSE, grs. x to ʒss. OFFICINAL PREP. _Potassæ Acetas_, L.E.D. (=I=) _Liquor Potassæ_ L.E.D. (=K=) _Potassæ Sulphuretum_ (=I=) L.E.D. _Potassæ Tart._ L.E.D. (=I=) _Liquor Arsenicalis_ (=I.L.=) ADULTERATIONS. Its degree of purity may be estimated by the quantity of nitric acid, of a given density, requisite for the saturation of a given weight. The purest _sub-carbonate_ is that obtained by incinerating _cream of tartar_, since most of the impurities are decomposed by the heat during the process, (_Sub-carbonas Potassæ Purissimus._ E.); it however generally contains lime.

POTASSÆ SULPHAS. L.E. SULPHAS KALI. D.

_Kali Vitriolatum_, P.L. 1787.

_Tartarum Vitriolatum, 1745, and 1720._

_Sal de duobus_, &c.

QUALITIES. _Form_, crystals which are right rectangular (but not square) prisms, modified on the edges and angles; or double six-sided pyramids with short intervening prisms, which are macles, or hemitrope crystals; they are slightly efflorescent, and when heated they decrepitate. SOLUBILITY. f℥j of water dissolves only grs. 24: the salt is insoluble in alcohol. INCOMPATIBLE SUBSTANCES. It is partially decomposed by the nitric and muriatic acids, in which case, a portion of the base being saturated, a corresponding portion of _bi-sulphate_ results; this fact illustrates a chemical law of some importance, viz. _that a substance less weakly attracted by another than a third, will sometimes precipitate this third from its combination with the second, in cases wherein a_ super, _or_ sub-_salt is readily formed_.[611] The history of tartrate of potass will furnish farther illustrations. See _page 183_. Sulphate of potass, when in solution, is entirely decomposed by _lime_ and _its compounds_; by _oxy-muriate of mercury_; _nitrate of silver_; and by _acetate_ and _sub-acetate of lead_. MED. USES. On account of its insolubility, it does not possess much activity as a purgative, but is said to be powerfully deobstruent; it should be exhibited in the form of powder, and in conjunction with rhubarb, or some other purgative medicine. DOSE, grs. x to ℥ss. _Form. 94._ From its hardness and insolubility, it is a most eligible substance for triturating and dividing powders. OFFICINAL PREP. _Pulv. Ipecac. co._ L.E.D. (=M=) Under the name _Sulphas Potassæ cum Sulphure_, the Edinburgh college retains the preparation formerly known by the name _Sal Polycrest_ (_Salt of many virtues_); and as it is produced by deflagrating nitre with sulphur, the product, besides sulphate of potass, contains _bi-sulphate_ and _sulphuret of potass_. It possesses no superiority over the common sulphate.

POTASSÆ SUPER-SULPHAS. L.

_Sal Enixum_ of Commerce.

QUALITIES. _Crystals_, long hexangular prisms; _Taste_, sour and slightly bitter. CHEMICAL COMPOSITION. It is a bi-sulphate, consisting of two proportionals of acid, and one proportional of base. SOLUBILITY. It is soluble in twice its weight of water, as well as in alcohol. MED. USES. It affords a convenient mode of exhibiting sulphuric acid combined with a saline purgative, in a solid form; as it is more soluble, so is it more active than the sulphate. DOSE, grs. x to ʒij. It forms a grateful adjunct to rhubarb. See _Form. 85._

POTASSÆ SULPHURETUM. L.E.

SULPHURETUM KALI. D.

_Kali Sulphuretum_, P.L. 1787. _Hepar Sulphuris._

QUALITIES. _Form_, a hard brittle mass; _Colour_, liver brown, hence the old name of _hepar_; _Taste_, acrid and bitter; _Odour_, none when dry, but if moistened, it yields the stench of sulphuretted hydrogen. CHEMICAL COMPOSITION. I consider this substance as a mixture of Sulphate of Potass, with variable quantities of Sulphuret and Bi-Sulphuret of Potassium.[612] INCOMPATIBLE SUBSTANCES. It is instantly decomposed by water, the oxygen of which forms Potass with the Potassium; while its hydrogen, combining with the sulphur, produces Sulphuretted hydrogen, part of which escapes, and another part forms, with the excess of Sulphur, Bi-Sulphuretted hydrogen; this latter body uniting with the base, produces what has been termed an _Hydroguretted Sulphuret_, but which might be more properly called an _Hydro-bi-Sulphuret_; upon adding an acid to the solution, a quantity of Sulphur is thrown down, Sulphuretted hydrogen is evolved, and a salt of Potass remains in solution. Metallic salts also decompose it, the metal falling down as a Sulphuret, or Hydro-sulphuret. MEDICINAL USES. It presents us with a form in which sulphur is soluble in water; it is diaphoretic, and has been found advantageous in cutaneous affections, (_Form. 118_,) and in arthritic and rheumatic complaints; while, from its known chemical action on metallic salts, it has been proposed as an antidote to such poisons. Its solution has been lately recommended as a lotion for the itch of infants, and in some cases it has been known to succeed after the sulphur ointment had failed.[613]

POTASSÆ SUPER-TARTRAS. L.E.

TARTARUM CRYSTALLI. E.

_Super-Tartrate of Potass._ _Crystals of Tartar._

QUALITIES. _Form_, small irregular brittle crystals, which when reduced to powder are termed _cream of tartar_. _Taste_, harsh and acid. CHEMICAL COMPOSITION. It is a _bi-tartrate_, consisting of two proportionals of acid and one proportional of potass. _Solubility._ It requires 120 parts of water at 60°, and 30 parts at 212°, for its solution; it is slightly soluble in alcohol. The watery solution of this salt was first observed by Berthollet to undergo a spontaneous decomposition by keeping, during which a mucous matter is deposited, and there remains a solution of carbonate of potass coloured with a little oil. It has long been regarded a pharmaceutical desideratum to increase the solubility of _cream of tartar_; Vogel discovered that it might be accomplished by combining it with boracic acid, and accordingly a formula has been introduced into the Codex Medicamentarius of Paris, for preparing a “_Tartras Acidulus Potassæ Solubilis, admixto Acido Boracico_.” The following is the process. Let thirty parts of boracic acid, and twenty parts of distilled water be heated together in a silver dish; as soon as this has been effected, add, in divided portions, 120 parts of super-tartrate of potass, taking care to shake the mixture continually; the whole will soon liquefy, (“_mire liquescent_,”) and by continuing the heat, a pulverulent mass will result. As it is extremely deliquescent it must be carefully preserved from the contact of the air; it dissolves in its own weight of water at 55°, and in half its weight at 212°. It is probable that the result is a new salt, in which the boracic and tartaric acids exist in combination,[614] but grant even that the chemical identity of the super-tartrate is preserved inviolate in the compound, I would ask what medical advantage can possibly attend the discovery? The peculiar value of cream of tartar depends doubtless upon its comparative insolubility, as I have already stated at page 173; modify this, and you will instantly change the medicinal effects of the salt; for like the neutral tartrate it will act upon the bowels, and therefore cease to undergo those changes _in transitu_ which are essential to its characteristic operation. Alum also has been observed by Berthollet to have in some measure the same effect in increasing the solubility of cream of tartar. INCOMPATIBLE SUBSTANCES. _Alkalies_ and _alkaline earths_; the _mineral acids_, &c. MED. USES. In doses of ʒiv to ʒvj, it acts as a hydragogue cathartic, producing a considerable discharge of serous fluid into the intestines; when however it is often repeated, it is liable to occasion debility of the digestive organs, and consequent emaciation: in smaller doses it acts as a diuretic. (_Form. 112._) ʒj in oj of boiling water, flavoured with lemon peel and sugar, forms when cool an agreeable beverage well known by the name of _Imperial_. A _Cream of Tartar Whey_ may be made, by adding to a pint of milk (when it begins to boil) ʒij of _Cream of Tartar_; the pan must then be removed from the fire, the whole suffered to cool, and the _whey_ separated from the curd by straining; this whey, diluted with warm water, furnishes an excellent drink in Dropsy. As it decomposes the carbonate of potass, the union of these salts will afford a very pleasant purgative draught. (_Form. 82._) OFFICINAL PREPARATIONS. _Pulv. Jalap. comp._ E. (=BM=) _Pulv. Scammon_. E. _Pulv. Sennæ comp._ L. _Ferrum Tartarizatum_, L. (=I=) _Antimonium Tartarizatum_ L.E. D. (_I_) _Soda Tartarizata_, L.E.D. (=I=) ADULTERATIONS. Super-sulphate of potass (_Sal Enixum_,) is the substance with which tartar is usually adulterated; it may be detected by its superior solubility, and by the solution affording with muriate of baryta a precipitate insoluble in muriatic acid.[615]

POTASSÆ TARTRAS. L. TARTRAS POTASSÆ.

Olim, Tartarum Solubile. E. TARTRAS KALI. D.

_Kali Tartarizatum._ P.L. 1787.

_Tartarum Solubile_. P.L. 1745.

QUALITIES. _Form_; this salt, although ordered to be crystallized, is generally kept in its granular form. _Taste_, bitter and cool. CHEMICAL COMPOSITION. It consists of one proportional of acid, and one proportional of base. SOLUBILITY. When in its crystalline form it is soluble in its own weight of water, but in its ordinary granular form, 4 parts are required for its solution; hence, compared with the insoluble super-tartrate, it has justly acquired the name of _soluble_ tartar; when long kept in solution, its acid is decomposed, and its alkali remains in a state of a _sub-carbonate_. It is also readily soluble in alcohol. INCOMPATIBLE SUBSTANCES. _Magnesia_, _baryta_, and _lime_; _acetate_ and _sub-acetate of lead_, and _nitrate of silver_ decompose it. All acids, even the _carbonic_,[616] and _acidulous salts_, _tamarinds_, and other _sub-acid vegetables_, by neutralizing a proportion of the base, convert it into the state of super-tartrate; this fact offers another illustration of the chemical law of affinity, explained under the head of _sulphate of potass_. The practitioner should bear this in his recollection, for I have frequently seen a dose of _soluble tartar_ directed in the acidulated _infusion of roses_; the result was of course very different from that which the author of the prescription intended to produce. MED. USES. It is a mild and efficient purgative, and forms a very valuable adjunct to resinous purgatives or to senna, the griping properties of which it corrects by accelerating their operation. _Form. 70._ DOSE, ʒj to ℥j, in solution.

PULVERES. L.E.D. _Powders._

For the administration and advantages of this form of preparation, see page 190. The following Officinal Formulæ offer some valuable combinations.

PULVIS ALOES COMPOSITUS. L. Pulvis Aloes cum Guaiaco. D. It consists of aloes _three parts_, guaiacum _two_ (=G=), and compound powder of cinnamon _one part_ (=O=). It combines sudorific and purgative effects. _Dose_, grs. x to ℈j. See _Form. 80_.

PULVIS ALOES CUM CANELLA. D. and P.L. 1807. Aloes _four parts_, white canella (=E=) _one part_. It is known in the shops by the name of _Hiera Picra_. The compound is more adapted for the form of pills than that of powder. It is very generally used by the lower classes, infused in gin. _Dose_, grs. x to ℈j.

PULVIS ANTIMONIALIS. L.D. Oxidum Antimonii cum phosphate Calcis. E. This preparation was introduced into the Pharmacopœia, as the succedaneum of the celebrated _fever powder of Dr. James_, the composition of which was ascertained by Dr. George Pearson. (_Phil. Trans._ lxxxi. 317.) It consists of 43 parts of the phosphate of lime, mixed, or perhaps chemically combined, with 57 parts of oxide of antimony, of which a portion is vitrified; and it is probable, that the difference of the two remedies depends principally upon the quantity of oxide which is vitrified: the specification of the original medicine is worded with all the ambiguity of an ancient oracle, and cannot be prepared by the process as it is described.[617] Experience has established the fact, that _James’s Powder_ is less active than its imitation; it affects the bowels and stomach very slightly, and passes off more readily by perspiration; in general however the difference is so inconsiderable, that we need not regret the want of the original receipt.[618] As it is quite insoluble in water, it should be given in powder, or made into pills. It is diaphoretic, alterative, emetic, or purgative, according to the extent of the dose and the state of the patient; in combination it offers several valuable resources to the intelligent practitioner. (See _Form. 119, 121, 125, 129, 134_.) But it may be fairly questioned whether this remedy has not been far too highly appreciated. Dr. James was certainly very successful in its use, but it must not be forgotten that he usually combined it with some mercurial, and always followed it up with large doses of bark.

PULVIS CINNAMOMI COMPOSITUS. L. Cinnamon bark _four_, cardamom seeds (=B=) _three_, ginger root (=B=) _two_, long pepper (=B=) _one part_. It is principally used to give warmth to other preparations, e. g. _Pulv. Aloes. comp_. L.D.

PULVIS CONTRAYERVÆ COMPOSITUS. L. Contrayerva, _five_, prepared shells, _eighteen parts_ (=M=). Dose, grs. x. to xl. It is said to be stimulant and diaphoretic.

PULVIS CORNU USTI CUM OPIO. L. Opium _one part_, burnt hartshorn _eight_, powdered cochineal _one part_. Ten grains contain one of opium.

PULVIS CRETÆ COMPOSITUS. Prepared chalk twelve parts, tormentil root (=G=), acacia gum (=M=), of each _six_, cinnamon bark _eight_ (=E=), long pepper (=E=) _one part_. It is antacid, astringent, and carminative. _Dose_, grs. v to ℈j.

PULVIS CRETÆ COMPOSITUS CUM OPIO. L. Compound powder of chalk _thirty-nine parts_, opium _one part_. _Form. 151._

Pulvis Ipecacuanhæ Compositus. L.E.D. Ipecacuan _one part_, opium (=H=) _one part_, sulphate of potass (=M=) _eight parts_. This combination has been long established in practice, as a valuable sudorific, under the name of _Dover’s Powder_. It affords one of the best examples of the power which one medicine possesses of so changing the action of another, as to produce a remedy of new properties; in this combination the opium is so modified, that it may be given with perfect safety and advantage in inflammatory affections accompanied with increased vascular action: it would seem that whilst the opium increases the force of the circulation, the ipecacuan relaxes the exhalant vessels, and causes a copious diaphoresis: the sulphate of potass is also an important ingredient, for experience has fully proved that ipecacuan and opium, in the same proportions, have not so powerful an effect without it; its action must be purely mechanical, dividing and mixing the active particles more intimately, and it appears that the success of the remedy depends very much upon its being finely powdered. _Dose_, grs. v. to ℈j, diffused in gruel, or in the form of a bolus. (See _Form. 120, 121, 122_.) The saline constituent in the original _Dover’s Powder_, was the result of the deflagration of nitre, and was therefore deliquescent; its dose was as much as from 40 to 70 grains. In the _Codex_ of Paris, this compound is directed to be prepared by melting together _four parts_ of sulphate of potass, with an equal proportion of nitrate of potass; to which when nearly cold is to be added, and well mixed by triture, _one part_ of pulverized extract of opium; the powders of ipecacuan and liquorice root, of each _one part_, are to be added last. It is evident that the proportions of opium and ipecacuan in this combination, are less than those in ours, and yet it is said to be more powerfully diaphoretic on account of the nitre. An arrangement, which is indebted for its medicinal virtue to a similar mode of operation, is presented in _Form. 130_.

PULVIS SCAMMONIÆ COMPOSITUS. L. Scammony and hard extract of jalap, of each _four parts_, ginger root (=E=) _one part_. The Edinburgh preparation of the same name differs very materially in composition, its ingredients being scammony and cream of tartar in _equal parts_.

PULVIS TRAGACANTHÆ COMPOSITUS. L. Powdered Tragacanth, acacia gum, and starch, of each _one part_; refined sugar, _two parts_. From what has been already stated under the head of mucilage of tragacanth, it appears to be a superfluous, if not an injudicious demulcent; and since starch is insoluble in cold water, the object for introducing it is not very obvious. _Form. 120._

Powders should be preserved in opaque green bottles, as they are materially affected by the action of light and air. Many of the compound ones should be considered as extemporaneous, and ought to be prepared only when they are required. The practitioner is also cautioned against purchasing any medicine in its powdered form, for so universal is the system of adulteration, that regular formulæ are observed in the wholesale houses for sophisticating powders, and Mr. Gray, in his “_Supplement to the Pharmacopœias_,” has given several specimens, under the title of “_Pulveres Reducti_.”

PYRETHRI RADIX. L.E.D.

(Anthemis Pyrethrum. _Radix._)

_Pellitory Root._

QUALITIES. The dried root is inodorous, but upon being chewed, it soon produces a pungent and peculiar sensation. SOLUBILITY. Alcohol, æther, and boiling water extract its virtues. CHEMICAL COMPOSITION. _M. Gautier_ has lately shewn that the peculiar pungency of the root depends on a fixed oil, which resides in vesicles in the bark. MED. USES. As a sialagogue, especially in cases of tooth-ache, and in paralysis of the tongue and muscles of the throat. (_Form. 143._) It also constitutes the basis of a very valuable gargle, in use at St. Bartholomew’s Hospital, for relaxation of the uvula and soft palate, as well as in certain cases of deafness depending upon an enlarged state of the tonsils. It is made by boiling ℥ss of the bruised root in oj of distilled water, until the fluid is reduced to one half; to which, when strained and cold, fʒij of _Liquor Ammoniæ_ are to be added.

PYROLA UMBELLATA.[619] _Ground Holly._

Although this plant has not yet found its way into the materia medica of the Pharmacopœia, its credited virtues entitle it to some notice in the present work. It was first brought into repute in this country by Dr. Somerville (_Med: Chirug: Trans: Vol. 5_). It is bitter, and consists of Resin, gum-resin, tannin, and bitter extractive. Alcohol and proof spirit are its best menstrua, but the watery infusion appears to contain all the virtues of the plant. MED. USES. It is said to be diuretic, tonic, and deobstruent; there is, however, no evidence to shew that it acts, specifically, on any other than the urinary organs. Dr. Ives, in the American edition of the present work, says, that as a diuretic medicine it has unquestionable merit, and that it will frequently mitigate symptoms of gravel, and strangury proceeding from other causes; he does not, however, agree with Dr. Barton, in considering it _Antilithic_. He has also given it, alternately with the _Uva Ursi_, in hæmaturia; the effects of severe and long continued gonorrhœal inflammation, with the most obvious benefit, and he considers it very analogous in its operation to the _Uva Ursi_. In some instances it has appeared to afford great relief in chronic cutaneous diseases. Further observation is necessary to define the mode and extent of its medicinal operation, but there is no hazard in saying that it is a medicine possessing considerable activity. Dr. Barton observes that this plant, like Uva Ursi, occasionally imparts a black tinge to the urine. DOSE ʒi to ʒij of the tincture; f℥ij to f℥iv of the infusion, prepared by pouring a pint of boiling water upon ℥j of the stalks and leaves.

QUASSIA. L.E.D. (Quassia Excelsa. _Lignum._)

_Quassia._

This wood owes all its properties to a peculiar bitter principle, which has been examined by Dr. Thomson and named _Quassin_; it is solid, slightly transparent, and of a yellowish-brown colour. (_See Infusum Quassiæ_.) It is said to owe its name to a West Indian negro, called Quassi, who first used it in fevers.

QUERCUS CORTEX. L.E.D.

(Quercus Pedunculata. _Cortex._)

_Oak Bark._

QUALITIES. _Odour_, none; _taste_, rough and astringent. CHEMICAL COMPOSITION. We are indebted to Sir H. Davy for a knowledge of this subject; he found that an ounce of the inner cortical part of young oak bark afforded by lixivation 111 grains of solid matter, of which 77 were _tannin_; and the cellular integument, or middle-coloured part, only yielded 43 grains of solid matter, of which 19 were _tannin_; and the epidermis furnished scarcely any quantity of _tannin_ or extractive; hence the bark should be selected from the smaller branches of the oak where the epidermis is still thin. Experience has, moreover, shewn that the quantity of _tannin_ varies considerably, not only according to the age and size of the trees, but according to the season at which they are _barked_; thus, the bark cut in spring contains, according to _Beguin_,[620] four times more of the astringent principle, than that which is obtained in winter. MED. USES. All its properties depend upon the presence of _tannin_, it is therefore only valuable as a powerful astringent; it is accordingly employed to check inordinate discharges, see _Decoctum Quercus_. Oak bark is sometimes administered in the form of powder, combined with ginger and other aromatics, and bitters, for the cure of intermittents, and it has frequently succeeded, but see page 167. Dose, ℈j to ʒss. In the form of poultice this powder is said to have proved highly useful to gangrenous sores. Its inhalation has also been supposed to prove beneficial in consumption; a striking case is related by Dr. Eberle of a man who had laboured under the usual symptoms of confirmed Phthisis, and who, at the time he went to grind in a bark-mill, was extremely weak and emaciated; in a short time, however, the cough, night sweats, and other hectic symptoms, began to abate sensibly, and in less than three months he was perfectly restored to health.

RHEI RADIX. L.E.D. _Rhubarb._[621]

Two varieties of this root are known in the shops, viz. _Turkey_ or _Russian_, and _East Indian_ or _Chinese_.

1. TURKEY or RUSSIAN. (_Rheum Palmatum._)

QUALITIES. _Form_, small round pieces, rather compact and heavy, perforated in the middle; _Colour_, lively yellow with streaks of white; it is easily pulverized, affording a powder of a bright buff-yellow colour. CHEMICAL COMPOSITION. Gum, resin, extractive, tannin, gallic acid, and a peculiar colouring matter, with traces of alumina and silex; the white or flesh-coloured streaks pervading its substance, consist of sulphate and oxalate of lime: according to the experiments of Mr. John Henderson, there is besides a peculiar vegetable acid, to which he has given the name of _Rheumic_ acid, but M. de Lassaignes has satisfactorily proved that this is no other than the oxalic acid: the purgative powers of the root appear to be intimately connected with its extractive and resinous elements, but the subject is still involved in considerable obscurity. SOLUBILITY. Water at 212° takes up 24 parts in 60, see _Infusum Rhei:_ by decoction, its purgative qualities are lost, and it becomes more bitter and astringent; alcohol extracts 2·7 from 10 parts, (see _Tinct. Rhei_.) MED. USES. In this substance, Nature presents us with a singular and most important combination of medicinal powers, that of an astringent, with a cathartic property; the former of which never opposes or interferes with the energy of the latter, since it only takes effect when the substance is administered in small doses, or if given in larger ones, not until it has ceased to operate as a cathartic; this latter circumstance renders it particularly eligible in cases of diarrhœa, as it evacuates the offending matter before it operates as an astringent upon the bowels. It seems to act more immediately upon the stomach and small intestines, and therefore in relaxed and debilitated states of these organs, it will prove an easy and valuable resource; it may, for such an object, be exhibited in conjunction with alkalies, bitters, and other tonics. Its cathartic property is most efficient when given in substance. It was formerly supposed that by toasting rhubarb we increased its astringency, but this process merely diminishes its purgative force, so that a larger dose may be taken. The colouring matter of rhubarb may be detected in the urine of persons to whom it has been exhibited; it does not however appear to possess any specific powers as a diuretic. DOSE, grs. vj to x as a tonic; ℈j to ʒss as a purgative; the operation of which is considerably quickened by the addition of neutral salts; the super-sulphate of potass forms also a very useful adjunct, and its acidulous taste completely covers that of the rhubarb. _Form. 83, 85._ Its powder, when sprinkled upon ulcers, is found to promote their healthy granulation. OFF. PREP. _Infus: Rhei_. L.E. _Vinum Rhei Palmati_. E. _Tinct. Rhei_. L.E.D. _Tinct. Rhei. comp_. L. _Tinct. Rhei cum Alöe_. E. _Tinct. Rhei cum Gentian_. E. _Pil. Rhei comp_. E.

2. EAST INDIAN, OR CHINESE. (_Rheum Undulatum?_)[622]

QUALITIES. _Form_, long pieces, sometimes flat, as if they had been compressed; they are heavier, harder, and more compact than those of the preceding species, and are seldom perforated with holes; _Odour_, stronger; _Taste_, more nauseous; white streaks less numerous, and they afford a powder of a redder shade than those of _Turkey_ rhubarb. CHEMICAL COMPOSITION. It differs from the _Turkey_ in containing less tannin and resin, and according to the experiments of Mr. A. T. Thomson, less oxalate of lime, in the ratio of 18 to 26. It contains however more extractive and gallic acid. SOLUBILITY. Water takes up one half of its weight, but the infusion, although more turbid, is not so deep coloured as that of Russian rhubarb; alcohol extracts 4 parts in 10. It habitudes with acids, alkalies, and neutral salts, differ likewise from those of the Russian variety, as Mr. A. T. Thomson has exhibited in a very satisfactory manner. (_London Dispensatory, Edit. 3, p. 474._) ADULTERATIONS. The inferior kinds of _Russian_, _East Indian_, and even _English_ rhubarb, are artfully dressed up and sold under the name of Turkey rhubarb. I am well informed that a number of persons in this town, known in the trade by the name of _Russifiers_, gain a regular livelihood by the art of dressing this article, by boring, rasping, and then colouring the inferior kinds; for which they charge at the rate of eighteen-pence per pound. The general indications of good rhubarb are, its whitish or clear yellow colour, and its possessing the other characteristic properties as above mentioned; it ought also to possess in an eminent degree the peculiar odour, for when this is dissipated, the powers of the medicine are nearly destroyed. In the form of powder, rhubarb is always more or less mixed with foreign matter; the detection of which can be alone effected by a trial of its efficacy.

RICINI[623] OLEUM. L.E.D. (_Ricinus Communis._)

_Castor[624] Oil._

QUALITIES. _Form_, a viscid and colourless, or pale straw-coloured oil; it is nearly inodorous, but on being swallowed, excites a slight sensation of acrimony in the throat. It has all the chemical habitudes of the other expressed oils, except those which relate to its solubility in alcoholic and ethereal menstrua. MED. USES. It is mildly cathartic, and is particularly eligible in cases where stimulating purgatives would prove hurtful, but in obstinate constipation, where copious evacuations are required, this oil cannot be trusted, it will insinuate itself through the intestinal canal, bringing with it a small portion of the more fluid contents, but leaving behind it the collection of indurated fæces. FORMS OF EXHIBITION. The most efficacious mode of administering it is by floating it upon tincture of senna, or peppermint water, or some other similar vehicle; it is also sometimes given with success in coffee or mutton broth, or suspended in water by the intervention of mucilage, yelk of egg (_Form. 75_,) or by honey, which at the same time contributes to its laxative operation: alkalies, although they form an emulsion with it, convert it into a saponaceous compound, and impair its cathartic force. DOSE, f℥ss to f℥iss. ADULTERATIONS. It is usually adulterated with olive oil or poppy oil, and when to a considerable extent, scammony is added to quicken its operation. There is however a peculiarity in castor oil which serves to distinguish it from every other fixed oil, viz. its great solubility in rectified spirit; for instance, f℥iv of alcohol of ·820 will mix uniformly with any proportion of castor oil, whereas it will not dissolve more than fʒj of _Linseed Oil_; and a still less proportion of the expressed oils of almonds and of olives; when the spirit is diluted, its action on all these oils is equally diminished, so that _common spirit of wine_ has but little power even over castor oil; but here chemistry again interposes its aid, for by the addition of camphor, in the proportion of one part to eight of spirit, spirit of ·840 is enabled to dissolve castor oil, whilst it has no influence upon the other fixed oils; castor oil is also soluble in any proportion, in sulphuric æther of the specific gravity ·7563, while four fluid-ounces of the same liquid will only dissolve a fluid-ounce and a quarter of the expressed oil of _Almonds_; a fluid-ounce and a half of that of _Olives_; and two fluid-ounces and a half of _Linseed oil_. Vogel introduced a composition as a substitute for this oil, which some practitioners have greatly extolled; it consisted of nine grains of the extract of Jalap, and three grains of Venetian soap, triturated in a mortar with an ounce and a half of Olive oil.

SABINÆ FOLIA. L. (Juniperus Sabina.)

_Savine Leaves._

QUALITIES. _Odour_, heavy and disagreeable; _Taste_, bitter, hot, and acrimonious. CHEM. COMP. Essential oil, which may be obtained by distillation with water; fixed oil, bitter extractive, and resin. SOLUBILITY. Both water and alcohol extract its active principles. MED. USES. It possesses highly stimulating properties, and has been used as a diaphoretic, anthelmintic, and emmenagogue. Rave, a German writer of great respectability, speaks of its use in chronic rheumatism in the highest terms; Alibert commends its anthelmintic powers, but its reputation has principally rested upon its generally acknowledged influence over the uterus. The testimony of Dr. Home of Edinburgh is strong in favour of its emmenagogue powers, but the adverse opinion of Dr. Cullen brought it into disrepute. It occasions a manifest flow of blood to the uterus, but this is probably sympathetically produced by its direct action on the large intestines; for if given in large doses it occasions great heat in the primæ viæ, hæmorrhage, and inflammation of the bowels. It is therefore inadmissible in all cases which are attended with fever, or much vascular action. When amenorrhœa depends upon a relaxed state of the general system, or on an inactive and torpid condition of the uterine system, it may often be employed with advantage. Wedekind, a German writer, extols it in the treatment of that atonic or relaxed state of the uterus, attended with an unnatural secretion and soft swelling of the uterus, which is sometimes met with in women who have suffered much from repeated childbearing, and which is so generally attended with a train of hysteric disturbances. Dr. Eberle says that he has occasionally employed it in cases of Amenorrhœa, in females of a relaxed habit of body; and although sometimes without success, he has had sufficient evidence of its powers to establish its claim to attention. In several cases, similar to those above stated, I have employed the Savin with much success, but I have found it very liable to disturb the stomach, and to produce head-ache. FORMS OF EXHIBITION. Some practitioners have recommended that of powder, but it is almost impossible to pulverize it without previously drying it at a temperature which will dissipate the essential oil, upon which its activity depends. The tincture affords a more convenient form, and a compound tincture formerly occupied a place in the Pharmacopœia, but has been abandoned. A decoction of an ounce of the leaves to a pint of water, with the addition of syrup, has been also recommended; an infusion, however, would be preferable. DOSE, of the powdered leaves from grs. v to x; of the tincture fʒj; of the decoction f℥ss to f℥j. As an external local stimulant, or escharotic, the dried leaves in powder are applied to warts, flabby ulcers, and carious bones; and the expressed juice diluted, or an infusion of the leaves, as a lotion to gangrenous sores, scabies, and _tinea capitis_; or mixed with lard and wax as an issue ointment. The German writers speak very highly of its effects as a poultice to old and obstinate sores. OFFICINAL PREP. _Oleum Volatile Juniperi Sabinæ_. E.D. (the dose of which is from one to three minims.) _Extractum Sabinæ_. D. (a very inert preparation.) _Ceratum Sabinæ_. L.

The experiments of Orfila have shewn that Savine exerts a local action, but that its effects depend principally on its absorption; through which medium it acts on the nervous system, the rectum, and the stomach. It still enjoys amongst the vulgar the reputation of being capable of producing absorption.

SACCHARUM. L.E.D. _Sugar._[625]

Sugar, as a pharmaceutical agent, is employed for accelerating the pulverization of various resinous substances, and when exhibited with the most acrid of them, it prevents their adhesion to the coats of the intestines, by which they might irritate and inflame them; it is also extensively used on account of its power in preserving animal[626] and vegetable substances. (See _Conservæ_.) Milk boiled with fine sugar will keep for a great length of time, and might be very conveniently employed during a long voyage. Dr. Darwin also observes that fresh meat cut into thin slices, either raw or boiled, might be preserved in coarse sugar or treacle, and would furnish a very salutary and nourishing diet to our sailors. Sugar exerts also some chemical affinities which are highly interesting to the pharmaceutic chemist. Vogel has published a paper to shew, that when sugar is boiled with various metallic oxides, and with different metalline salts, it has the property of decomposing them; sometimes reducing the oxide to the state of a metal, and at others depriving the oxide only of one of the proportionals of oxygen; thus _sulphate of copper_ and _nitrate of mercury_ are precipitated in a metallic form, whilst _peroxide of mercury_ and _acetate of copper_ are converted into protoxides; _corrosive_ sublimate is changed into _calomel_, but _calomel_ is not susceptible of any further decomposition. All those metallic salts which have the power of decomposing water are not affected by sugar, as those of _iron_, _zinc_, _tin_, and _manganese_. It appears, moreover, that sugar has the property of rendering some of the Earths soluble in water. Sugar in water, at the temperature of 50°, is capable of dissolving one half of its weight of lime; the solution thus produced is of a beautiful white-wine colour, and has the smell of fresh-slacked quick-lime. It is precipitated from the solution by the _carbonic_, _citric_, _tartaric_, _sulphuric_, and _oxalic_ acids; and it is decomposed, by double affinity, by _caustic_ and _carbonated potass_ and _soda_, and by the _citrate_, _tartrate_, and _oxalate of potass_, &c. The union of sugar with the alkalies has been long known, and in the decomposition of the solution of lime in sugar by the salts above mentioned, the acid unites with the lime, and the alkaline base forms a compound with the sugar.

SAPO. L.E.D. _Soap._

I. Durus. (_Hispanicus._) _Hard_, or Spanish Soap.

CHEMICAL COMPOSITION. Oil 60·94, soda 8·56, water 30·50; the water is partially dissipated by being kept, and the soap therefore becomes lighter. Muriate of Soda is also an essential ingredient[627] of _hard_ soap. SOLUBILITY. Water dissolves about one-third of its weight of genuine soap, and forms a milky solution; alcohol also dissolves it, and affords a solution nearly transparent, although somewhat gelatinous.[628] INCOMPATIBLE SUBSTANCES. 1. All acids and acidulous salts, which combine with the alkali, and develope the oil. 2. Earthy salts, e. g. _Alum_; _muriate_ and _sulphate of lime_; _sulphate of magnesia_. 3. Metallic salts. _Nitrate of silver_; _ammoniated copper_; _tincture of muriated iron_; _ammoniated iron_; _acetate_, _sub-muriate_, and _oxy-muriate of mercury_; _sub-acetate of lead_;[629] _tartarized iron_; _tartarized antimony_; _sulphate of zinc_, _copper and iron_. 4. All astringent vegetables. 5. Hard water. MEDICINAL USES. In large doses it is purgative; in smaller ones, it is decomposed _in transitu_, and its alkali is carried to the kidneys; in this way it may act as a lithonthriptic; or it may produce its effects by correcting any acidity which may prevail in the _primæ viæ_, for the weakest acid is capable of decomposing soap, and of uniting with its alkaline base; a solution of soap in lime water was long regarded as one of the strongest solvents of urinary calculi that could be administered with safety, but the result of such a mixture is an insoluble soap of lime, and a solution of soda; in habitual constipation, and in biliary obstructions, it is frequently prescribed in conjunction with rhubarb, or some bitter; in which cases it can only act as a laxative, or as a chemical agent, in increasing the solubility of the substance with which it is united. It has been also given in solution as an antidote to metallic poisons, and it is often successfully injected as a clyster, in unrelenting and habitual costiveness; as an external application, it is used in the form of liniment, (see _Linimenta_.) Its pharmaceutical value, in forming pill-masses, has already been considered (_page 196_), and the following _formulæ_ afford examples of such an application, viz. 14, 80, 105, 118, 165. OFFICINAL PREPARATIONS. _Pil. Saponis cum Opio_. L. (=L=). _Pil. Scillæ comp_. _L._ (=M=). _Pil. Aloet_. E. (=L=). _Pil. Aloes et Assafœtidæ_. E. (=I=). _Pil. Aloes cum Zinzib_. D. (=L=). _Pil. Colocynth. comp_. D. (=L=). _Emplast. Saponis_. L.E. _Ceratum Saponis_. L. _Liniment. Saponis. comp_. L. _Liniment. Saponis cum Opio_. L. ADULTERATIONS. Pulverized Lime, Gypsum, or Pipe clay, are sometimes added; but the fraud is easily detected by solution in alcohol, when the earthy matters fall down.