quarter of a grain, gradually increased to four or ive grains.

Liquor cupri ammoniat. London.-Solution of ammoniated copper.

Take of ammoniated copper a drachm, distilled water a pint. Dissolve the ammoniated copper in the water, and let the solution be filtered through paper.

The quantity of water used by the London college is stated to be too much, it being a curious fact that the salt is more soluble in a smaller quantity of water, owing to the larger quantity decomposing the subsulphate of copper and leaving an insoluble oxide of copper, which is precipitated.'

Medical properties.-Principally used as a detergent to foul ulcers.

Solutio sulphatis cupri composita. Edinburgh. -Compound solution of sulphate of copper.

Take of sulphate of copper, sulphate of alumina, each three ounces; water two pounds; sulphuric acid one ounce and a half. Let the sulphates be boiled in the water in order to dissolve them, and then add the acid to the liquor Efiltered through paper.

Qualities. The color of ferrum ammoniacum is of an orange yellow it has an odor of saffron and rather a styptic taste. It is soluble and deliquescent.

Medical properties.-Tonic and emmenagogue. From being somewhat aperient it is occasionally admissible in cases where other forms of the metal would disagree. We have found it very useful when the combination is required of a deobstruent and tonic. Dose from grs. iij. to f

or more.

Subcarbonas ferri præparatus. Edinburgh.Prepared subcarbonate of iron.

Let purified filings of iron be frequently moistened with water till they fall into rust, which rust is to be rubbed into powder.

Qualities.-Color of a reddish brown; taste styptic; very little smell.

Medical properties--Rust of iron has lately been used for tic douleureux. As a tonic and emmenagogue, and vermifuge, in ordinary cases, the dose is from grs. v. to grs. xv.

Ferri subcarbonas. London.-Subcarbonate of iron.

Take of subcarbonate of iron, muriatic acid, muriate of ammonia, each a pound. Pour the muriatic acid upon the subcarbonate of iron, and set it aside until bubbles cease to arise. Let the solution be filtered through paper and boiled to dryness. Mix intimately the residuum with the muriate of ammonia; then directly sublime by the application of a strong heat: lastly reduce the sublimed matter to powder.

Murias ammonia et ferri. Edinburgh.-Muriate of ammonia and of iron.

Take of red oxide of iron washed and again dried, muriate of ammonia, each equal parts by weight. Mix them well together, and let them be sublimed by a quick fire. Reduce the sublimation to powder, and preserve it in a well stopped phial.

In the process ordered by the London college we are told that a mixture of muriate of ammonia and permuriate of iron is produced: the whole of the subcarbonate of iron employed is not dissolved in the acid.

of soda be dissolved separately in four pints of water; then mix the solutions together, and set the mixture aside in order that the powder may subside; then decant off the supernatant fluid; wash the subcarbonate of iron in hot water, and let it be dried, wrapped up in bibulous paper, with a gentle heat.

Carbonas ferri præcipitatus. Edinburgh.-Precipitated carbonate of iron.

Take of sulphate of iron four ounces, subcarbonate of soda five ounces, water ten pounds. Let the sulphate be dissolved in the water; then add the subcarbonate previously dissolved in the water, and mix them together. Wash the carbonate of iron which is precipitated with tepid water, and afterwards dry it.

Here a double decomposition is effected the sulphuric acid of the sulphate of iron unites with the soda, aud the carbonic acid is attracted by the iron.

Qualities.-Taste but slightly styptic. Color brown. No smell. Insoluble in water. Decomposible by heat.

Medical properties.-Nearly the same as the last. When given fortic douleureux the dose is sometimes a drachm frequently repeated.

Ferri sulphas. London.-Sulphate of iron. Take of iron, sulphuric acid, each eight ounces, water four pints. Mix the acid with the water in a glass vessel, and to these add the iron; then, when the effervescence is over, let the solution be filtered through paper; and, after due evaporation, set it apart for crystals to form. Having poured off the liquor, let the crystals be dried on bibulous paper.

Sulphas ferri. Edinburgh.-Sulphate of iron. Take of iron and sulphuric acid of each by weight eight ounces, water four pints. Mix the sulphuric acid with the water in a glass vessel, and put the iron to them. When the effervescence is over, filter the solution through paper, and after due evaporation set it apart that crysta's may

form. The liquor being poured off, dry the crystals on bibulous paper.

In these processes a sulphate of oxide of iron is formed, the oxygen of part of the water combining with the metal, and its hydrogen being sent off in a gaseous form. The oxide thus produced unites with the sulphuric acid, and a sulphate is formed, which is dissolved in that part of the water which has not undergone decomposition. Qualities.-Color green, taste styptic, very little odor. Soluble in water and fusible by heat. Decomposed by the following substances, 'the earths, the alkalies and their carbonates; lime water, borate of soda, phosphate of soda, muriate of barytes, nitrate of silver, acetate of lead, and every salt the base of which forms an insoluble compound with sulphuric acid and soaps. It is also decomposed by all infusions of vegetable astringents.'

Medical properties.-Tonic, deobstruent, anthelmintic, and emmenagogue. A very useful preparation. Dose from gr. i. to gr. v. Sulphas ferri exsiccatus. Edinburgh.-Dried sulphate of iron.

The Dublin college properly order this oxide to be washed in order to separate a portion which still remains of the red sulphate.

Ferrum tartarizatum. London.-Tartarised iron.

Take of iron a pound, supertartrate of potassa in powder two pounds, water five pints, or a sufficient quantity. Let the iron and the supertartrate be rubbed together, and subject the mixture in an open glass vessel with a pint of water to the action of the air for twenty days, daily stirring them and preserving a moisture in the mass by additions of distilled water. Then boil it in four pints of distilled water during fifteen minutes, and filter the solution. Evaporate in a water-bath until the tartarised iron be quite dry. Let it be reduced to powder, and preserved in a stopped bottle.

Tartras potasse et ferri. Edinburgh.-Tartrate of potassa and of iron.

Take of purified filings of iron one part, supertartrate of potassa in powder two parts, water one part. Rub them together and expose them to the air in a shallow earthen vessel for fifteen days, stirring the mass daily with a spatula, and keeping it moist by frequent additions of water. Then let the whole be boiled for a short time in four times its weight of water, and pour off the solution from the other faces. Evaporate the solution to dryness in a water-bath; and, having rubbed the mass into powder, let it be kept in a well stopped bottle.

It is suggested by Dr. Thomson that the proportion of supertartrate of potassa employed in these preparations may not be sufficient for the

quantity of metal; the intention is first to oxide the iron by a partial decomposition of the wate employed, and then to combine this oxide the superabundant acid of the supertartrate of potassa.

Qualities. The color of this preparation is f a brownish green; it is without smell, and l but a slightly styptic taste. The strong acid. lime water, hydrosulphuret of potassa, and i fusions of astringent vegetables decompose i and are therefore incompatible in formule wit it.'

Medical properties.-This form of iro been supposed particularly applicable in dreng. | as combining a diuretic with a tonic quality Dose Ofs to 3.

Liquor ferri alkalini. London.-Solution alkaline iron.

Take of iron two drachms and a half, ne acid two fluid ounces, distilled water six fai ounces, solution of subcarbonate of potassa fluid ounces. Mix the acid and the water tege ther, pour the mixture over the iron; and when the effervescence shall have ceased pour of the acid and solution. Add this gradually and a intervals to the solution of subcarbonate of tassa frequently agitating until it become of a brownish red color and no further effervescence be excited. Finally, set it aside for six hour and pour off the liquor.

In this preparation the diluted acid first on dises the iron, and, when the subcarbonate of potassa, is added, carbonic acid is extracted and a red precipitate formed, which is ultimately dis solved by the excess of potassa.

Qualities.--Taste slightly styptic and alkaline, exciting a sensation of coldness in the mouth Water precipitates the alkaline iron, leaving a clear fluid supernatant, which yields, upon e poration, crystals of nitrate of potassa.

Medical properties.-The same with the other preparations of iron; but scarcely at all eployed on account of the uncertainty of its com position and strength.

London.-Time

Tinctura ferri ammoniati. ture of ammoniated iron. Take of ammoniated iron four ounces, proof spirit a pint. Digest and filter. Tinctura ferri muriatis. London.-Tincture of muriate of iron.

Take of carbonate of iron half a pound, m riatic acid a pint, rectified spirit three pints. Let the acid be poured over the carbonate of iron in a glass vessel, and let the mixture be occasionally shaken for three days. Set it apart that the fæces, if there be any, may subside; then pour off the solution and add to it the spirit.

Edinburgh. Take of black oxide of iron pu rified and reduced to powder three ounces, m riatic acid about ten ounces, or sufficient to dis solve the powder. Digest with a gentle heat, and, the powder being dissolved, let so much alcohol be added as will make the whole liquor amount to two pounds and a half.

The London preparation is of a more uniform strength than the Edinburgh formula.

Qualities. This tincture has a very styptic taste, and is of a yellowish brown color. It contains the iron in the state of a chlorate, and

when it is distilled a black oxide of iron remains in the retort. With the alkalies and their carbonates it gives a red precipitate, strikes a black color with infusions of astringent vegetables, and forms with mucilage of acacia gum an orange colored jelly. Hence these substances cannot enter into compositions with this tincture.'

Medical properties.-A useful preparation of iron. It has been given in large doses under some circumstances of suppression of urine. Dose generally from mxv. to f. 31.

Vinum ferri. London.-Wine of iron. Take of iron one drachm, supertartrate of potassa in powder six drachms, distilled water two pints or so much as will be necessary, proof spirit twenty fluid ounces. Rub the iron and the supertartrate of potassa together, and expose them in an open glass vessel with one fluid ounce of water to the air for six weeks, stirring daily with a spatula, and frequently adding so much distilled water as may be necessary to keep a moisture in the mass. Then dry it with a gentle heat, rub it to powder, and mix it with thirty fluid ounces of distilled water. Let the solution be filtered and then add the spirit.

Qualities. This is a solution of tartrate of iron and potassa, with an excess of supertartrate of potassa,' the iron being being oxidised and dissolved in the acid of the supertartrate. Medical properties.-A pleasant preparation of iron. Dose from f. 3j. to f. 31. PREPARATA EX HYDRARGYRO.-Preparations

of mercury.

Hydrargyrum cum creta. London.-Mercury with chalk.

Take of purified mercury (by weight) three ounces; prepared chalk five ounces. Let them be rubbed together until the globules entirely disappear.

In this preparation something seems to be effected between oxidisement and merely mechanical division of the mercury.

Medical properties.-A most excellent alterative, especially in complaints of children that are marked by lymphatic weakness and mesenteric obstruction. Dose for an adult from grs. vi. to 9j.

Hydrargyri nitrico oxydum. London.-Nitric oxide of mercury.

Take of purified mercury (by weight) three pounds, nitric acid by weight a pound and a half, distilled water two pints. Mix them in a glass vessel and boil until the mercury be dissolved, and a white mass remain after the water is evaporated. Rub this into powder, and put it into another very shallow vessel; then expose it to a gentle heat, and let the fire be gradually raised until red vapors no longer be emitted. Oxydum hydrargyri rubrum per acidum nitricum. Edinburgh.--Red oxide of mercury by

nitric acid.

Take of purified mercury three parts, diluted nitrous acid four parts. Dissolve the mercury, and evaporate the solution over a gentle fire to a white dry mass, which, being reduced to powder, is to be put into a glass cucurbit, and covered with a thick plate of glass. Then adapt a capital to the vessel, and having placed it in a sand-bath let the contained matter be roasted with a fire

gradually raised until small red scales be formed.

Qualities. When properly prepared this is a peroxide mixed with some nitrate of mercury.' It appears in the form of bright red scales which are corrosive and acrid; they are insoluble in water but totally soluble in nitric acid, and decomposible by a red heat. It is sometimes adulterated with red oxide of lead, which may be detected by dissolving one part of the oxide in four of acetic acid; if lead be present the solution has a sweetish taste; and, when sulphureted water is dropped into it, a dirty dark precipitate is thrown down. When pure it is perfectly volatilised when thrown on a red hot iron.'

Medical properties.-This, the red precipitate of common language, is only used as an external application in cases of chronic, inflammatory, and old sores.

Acetas hydrargyri. Edinburgh.-Acetate of mercury.

Take of purified mercury three ounces, diluted nitrous acid four ounces and a half, or a little more than is necessary to dissolve the mercury, acetate of potassa three ounces, boiling water eight pounds. Mix the mercury with the acid; and towards the cessation of the effervescence digest, if necessary, until the mercury be completely disolved. Then dissolve the acetate of potassa in the boiling water, and immediately to this solution, still hot, add the former, and mix them together by agitation. Set the mixture aside to crystallise; then wash the crystals placed in a funnel with cold distilled water, and finally dry them with a very gentle heat.

In preparing the acetate of mercury it is necessary that all the vessels which are used, and the funnel, be of glass.

In this preparation a nitrate of mercury is first procured by the action of the nitrous acid upon the metal, which nitrate is decomposed by the potassa of the acetate uniting with the acid of the salt; in this way a nitrate of potassa is procured which remains dissolved; and the acetic acid of the acetate combines with oxidated metal, and thus forms the acetate of mercury.

Qualities. This salt should appear in small flat crystals of a silvery whiteness: it is acrid to the taste; soluble in hot water, but not in alcohol, and decomposed by alkalies and heat.

Medical properties.-It is a form of mercury not much used; in the proportion of grs. ii. to f. 3ij. of rose water, some have recommended it as a wash in certain cutaneous disorders. Dose gr. i. twice a day.

Hydrargyri oxydum cinereum. London.-Gray oxide of mercury.

Take of submuriate of mercury an ounce, lime-water a gallon. Boil the submuriate of mercury in the lime-water, stirring it assiduously until the gray oxide of mercury subside. Let it be washed with distilled water, and then dried. Oxidum hydrargyri cinereum. Edinburgh.— Gray oxide of mercury.

Take of submuriate of mercury half an ounce, lime-water five pounds. Boil the submuriate in the solution for a quarter of an hour in a slightly covered vessel. Pour off the supernatant fluid, and let the oxide be washed with distilled water and dried.

The lime water decomposes the submuriate, and the gray precipitate is a protoxide. If calomel be considered a proto-chloride of mercury, we must admit (says Dr. Thomson) that the water of the lime-water is decomposed, and its hydrogen, uniting with the chlorine, forms muriatic acid, which converts the lime into a muriate, while its oxygen changes the mercury into the protoxide.

Qualities.- Color gray. Insipid, without smell, and insoluble in water.

Medical properties.-Some have considered this preparation as an exceedingly useful form of mercury, partly on account of the uniformity of its strength. Dose from gr. i. to grs. iij.

Hydrargyri oxydum rubrum. London.-Red oxide of mercury.

Take of purified mercury (by weight) a pound. Put the mercury into a tall glass vessel with a narrow mouth and broad at the bottom. Subject this vessel open to a heat of 600° until the mercury be converted into red scales, which are then to be rubbed into a fine powder.

The heat in this process volatilises the mercury, and the metal in this state attracts oxygen from the air and is thus converted into a red oxide.

Qualities. This preparation produces sparkling deep red scales, which are small and exceedingly brilliant, without odor, but of a sharp caustic taste.

Medical properties.-Formerly it was considered an excellent form of mercury for syphilis, but is at present very little employed. Dose from one-sixth or eighth of a grain to one grain. It is apt to affect the bowels, and is therefore usually combined with opium. It is employed by some externally as an escharotic.

Hydrargyri oxymurias. London.-Oxymuriate of mercury.

Take of purified mercury (by weight) two pounds, sulphuric acid thirty ounces (by weight), dried muriate of soda four pounds. Boil the mercury with the sulphuric acid in a glass vessel until the sulphate of mercury become dry; rub this when cold with the muriate of soda in a mortar of earthenware; then sublime it in a glass cucurbit, with a heat gradually raised.

Murias hydrargyri corrosivus. Edinburgh. Corrosive muriate of mercury.

Take of purified mercury two pounds, sulphuric acid two pounds and a half, dried muriate of soda four pounds. Boil the mercury with the sulphuric acid in a glass vessel placed in a sand bath until the material become dry. Mix this when cold in a glass vessel with the muriate of soda; then sublime in a glass cucurbit with a heat gradually raised. Separate the matter sublimed from the scoria.

According to the latest doctrines, the chlorine of the common salt leaves the sodium and uniting with the mercury of the hypersulphate forms a bichloride of mercury which sublimes, while the oxygen of the oxide of mercury combining with the sodium converts it into soda, which unites with the sulphuric acid, and forms sulphate of soda which remains in the bottom of the cucurbit.'

Qualities-Corrosive sublimate, as it was formerly called, appears in the form of very small

shining white crystals, which have a very acti taste, and are without smell; they effloresce by exposure to the air. It is soluble in water, ako hol, and the acids. Alkalies and oils precipita and reduce it. 'It is also decomposed by sol tions of tartrate, of potassa, and antimony, a trate of silver and acetate of lead, and forms pr cipitates in infusions and decoctions of the following vegetable substances. Camomiledes ers, horse radish root, columba root, catechu, cichona-bark, rhubarb root, senna leaves, anaruba bark, oak bark, tea, and in the almani mixture, consequently it is incompatible in er temporaneous formula with these substances

Medical properties.-Formerly very much ployed in syphilitic affections; and still cost tuting the main ingredient of several pater medicinals which profess to contain no mercur in their composition. At present it is more asi in chronic affections of the skin than in any other disorder, whether these have or have not syphilitic origin and character. Dose from on tenth of a grain to a fourth, two or three times a day.

Liquor hydrargyri orymuriatis. London. Solution of oxymuriate of mercury.

Take of oxymuriate of mercury eight grain, distilled water fifteen fluid ounces, rectified spe rit a fluid ounce. Let the oxymuriate of mercu ry be dissolved in the water and the spirit added.

The dose of this solution is from f. 33. to f. each fluid ounce containing half a grain of the salt. The solution should not be kept long nor exposed to a strong light, as it thus becomes de composed and throws down calomel. This solution is externally useful in tetters diluted with

half its measure of water.

Hydrargyrum præcipitatum album. London- ! White precipitated mercury.

Take of oxymuriate of mercury half a pound, muriate of ammonia four ounces, solution of subcarbonate of potassa half a pint, distilled wan four pints. Dissolve first the muriate of ammonia, then the oxymuriate of mercury in the dis tilled water, and add to the mixed solution the solution of subcarbonate of potassa. Let the precipitated powder be washed until it become tasteless, then it is to be dried.

of

The Dublin College order the precipitate to be made by an addition to the fluid poured from the precipitated submuriate of a quantity of water of ammonia, which Dr. Thomson remarks is a more simple and a more economical mode of obtaining the product. The corrosive muriate, it will be recollected, is held in solution by the fluid in question, and is precipitated by the ammonia.

Qualities.-Muriate of mercury and ammonia (so Dr. Thomson names it) is without smell of taste; it is a smooth white insoluble powder. When adulterated with white lead the fraud may be detected by digesting one part of it in four parts of acetic acid, and adding to the solution a small quantity of sulphuret of ammonia; a black precipitate, insoluble in sulphuric acid, indicates the presence of lead. Chalk and starch are also sometimes mixed with it, and may detected by heating the preparation in an iron spoon; if pure it is completely volatilised, butif

be