Chapter LXXVII: Part 2 (38)

The cause of tetanus, in temperate climates, is generally irritation of the nerves, arising from local injuries, especially punctured or lacerated wounds. Of these the most trivial are occasionally sufficient to produce locked-jaw. In hot climates the disease is occasionally produced by exposure to cold, or by suddenly suppressed perspiration. The last variety is curable; the former one scarcely ever so. The proper treatment is a matter still undetermined. Sedatives, antispasmodics, and powerful stimulants, have each had their advocates. Large doses of wine and spirits, in conjunction with opium, have occasionally been administered with success. Electricity and the vapour bath have also proved useful. In all cases the bowels should be moved by active aperients, either by the mouth or per anum. Dr Shrimpton[231] recommends the Chinese mode of treating tetanus, which is as follows:——From four to five grains of solid opium are mixed with tea-leaves, or dried roses, and carefully beaten together with molasses. The patient smokes this mixture, and endeavours to draw the smoke into the lungs, leaving off when the narcotic effects are produced. These last generally from three to four hours. The same operation should be repeated whenever there are any signs of returning spasms.

[Footnote 231: ‘Lancet,’ 1871, vol. ii, page 547.]

=TET′TERS.= The popular name of several cutaneous diseases, the treatment of which can only be properly undertaken by the experienced medical man.

=THAL′LIUM.= Tl. [Eng., L.] A heavy metal, belonging to the mercury, silver, and lead group, discovered by Crookes in the early part of 1861, and displayed by him as “a new metallic element” at the opening of the International Exhibition, on the 1st of May, 1862. Thallium is a widely-diffused metal, being found in many minerals, particularly in iron- and copper-pyrites and native sulphur. It has recently been obtained in comparatively large quantities from the dust of the flues leading to sulphuric acid chambers. The spectrum of thallium consists of a single most characteristic line of a beautiful green colour. The spectrum produced when the metal is burnt in the electric arc is, however, more complicated, and consists of several green, blue, and other lines.

Thallium melts at 550° Fahr., and at a less heat may be readily welded, a property that has hitherto been regarded as peculiar to iron and platinum. Its specific gravity varies from 11·8 to 11·9, according to the mode of preparation. When freshly cut it has a dull white colour, destitute of the brilliancy of polished silver. Exposed to the air, it tarnishes rapidly, a straw-coloured oxide making its appearance on the surface. The oxide is alkaline and caustic to the taste, and much more soluble than the oxides of silver and lead. The metal is remarkable for its strongly marked diamagnetic characters, resembling bismuth in this respect. The alloys of thallium are very remarkable. Copper, alloyed with only one half per cent, of thallium, becomes quite brittle; but the alloy with tin is malleable. Mr Crookes has prepared a great number of the salts of this interesting metal. These need not be described here, as they have not yet been applied to any use in the arts. See SULPHURIC ACID.

=THALLOGENS.= Thallogens or Thallogenous plants are structurally the simplest of the acotyledonous, or flowerless plants, consisting simply of a collection of cellular tissue, called a _thallus_. They are entirely destitute of woody fibre. The _Algæ_, _Characeæ_, _Fungi_, and Lichens are thallogenous plants.

=THEBA′INE.= C_{19}H_{21}NO_{3}. _Syn._ THEBAIA, PARAMORPHIA. A crystalline substance obtained by Thibourméry from an infusion of opium that has had its morphia extracted by acting on it by an excess of lime.

=THE′INE.= C_{8}H_{10}N_{4}O_{2}. _Syn._ THEINA. An alkaloid extracted from tea. It is identical with caffeine, and may be obtained from tea in the same manner as that substance is from coffee. The best ‘gunpowder tea’ contains fully 6% of theine, about one half of which is lost in the present careless mode of making infusion of tea for the table.

Mr Lewis Thompson, M.R.C.S., in a contribution to the ‘Medical Times and Gazette’ for 1871, directs attention to the value of theine as a therapeutic agent, as well as gives an easy method for its preparation. He writes as follows:——“I wish to direct the attention of the medical profession to a valuable agent which has hitherto escaped notice, although its powers are most unquestionable, and its cost price very trivial. The article to which I allude is theine, a substance existing in tea and coffee, and, as I believe, in many other vegetable products.

“As a medicine, theine is powerfully tonic and stimulant, and appears to possess the tonic virtues of the disulphate of quinia united to the stimulating power of wine, but with this difference, that the stimulus from theine is not followed by depression, as in the case of wine and alcohol.

“Theine seems to act chiefly on the great sympathetic or ganglionic system of nerves, and but slightly on the brain. I have used it in doses of from 1 to 5 grams, with very marked advantage, in the low stage of typhoid fevers, confluent smallpox, and that form of mortification of the toes which is so singularly fatal to old people. But, in addition to this, different medical friends of mine have found it useful in hemicrania, neuralgia, and what has been called relapsing fever; and in the case of an overdose of opium, it appeared to relieve the narcotic symptoms speedily.

“With regard to the cost of this medicine, I have discovered that in the ordinary process of roasting coffee, the whole of the theine is driven off before the torrefaction of the coffee is completed; and thus theine may be cheaply collected by making the axis of the coffee roaster tubular. If, instead of a solid axis, we employ at one end of the roasters a tube passing away to the distance of about three feet, the theine is condensed in this tube by the refrigerating power of the atmosphere, and may afterwards be easily dissolved out by a little water, and purified in the manner about to be indicated.

“As the result of much experience, I have obtained on an average, 75 grains of theine from the roasting of 1 lb. of raw coffee; and when we reflect that in Great Britain alone, there are more than 13,000 tons of coffee roasted annually, we see that about 140 tons of theine are wasted and lost every year by sheer ignorance. It may, perhaps, be thought that the saving of the theine will damage the flavour of the coffee, but from experience I know that it has no such effect; and, in point of fact, it is an advantage to the flavour of the coffee to make both the axes of the roaster tubular, and to cause a gentle current of air to pass through the apparatus during the roasting of the coffee, so as to expel the empyreumatic products that are formed. I will now relate the fact upon which the purification of theine depends, and when this is once clearly understood, the manufacture of theine from either tea or coffee becomes an extremely simple matter. Theine is absolutely insoluble in a concentrated solution of the carbonate of potash, and thus we may precipitate it from its admixture with sugar, mucilage, and vegetable extract. If, then, by means of the subacetate of lead, we have removed from a vegetable infusion the tannin, malic acid, &c., we have only to evaporate the filtered solution to a small bulk, and add to it its own weight of dry carbonate of potash, and the whole of the theine becomes at once insoluble; so that having collected this insoluble product, and boiled it in rectified spirits of wine, we have a solution of pure theine, which, after distilling off the spirit, furnishes crystals fit for immediate use. In conclusion, I will merely mention a distinctive test for theine, sufficiently delicate to detect the one thousandth of a grain of that substance. Dissolve the theine in a small quantity of water, and pass through this a stream of euchlorine, then allow the fluid to evaporate at a steam heat; a blood-coloured substance will remain, which, on the application of a few drops of cold water, forms a beautiful scarlet solution like red ink. It is, I apprehend, almost unnecessary for me to say that euchlorine gas is formed by the action of hydrochloric acid upon the chlorate of potash.

“I ought, perhaps, to add that theine collected as a waste product of coffee, and purified by myself, has cost me less than threepence per ounce troy.”

=THENARD’S BLUE.= See ULTRAMARINE (Cobaltic).

=THEOBROMÆ OLEUM.= _Syn._ CACAO BUTTER. A concrete oil, obtained by expression and heat from the ground seeds of _Theobroma Cacao_. Occurs in cakes of a yellowish colour, of a pleasant cacao odour. Does not become rancid from exposure to air. Contained in all the suppositories.

_Not official._——The following form good bases for suppositories:——Theobroma oil, when melted, begins to solidify at 72° Fahr.; stearine of cocoa-nut oil at 75° Fahr.; 4 of stearine and 2 of mutton fat at 77° Fahr.; 4 of stearine and 1 spermaceti at 80° Fahr. Stearine alone is, perhaps, a better substance than cacao butter for making suppositories. It begins to solidify at 78° Fahr., but there is stearine that solidifies at 120° Fahr.; this will not answer for suppositories.

=THEOBRO′MINE.= A peculiar principle, closely resembling caffeine or theine, found by Woskresensky in the seed of the _Theobroma Cacao_, or the nuts from which chocolate is prepared. Its form is that of a light, white, crystalline powder, which is rather less soluble than caffeine. It is obtained like caffeine. See COCOA.

=THERI′ACA.= A name given in ancient pharmacy to various compound medicines, chiefly electuaries or confections, employed as antidotes to poisons or infection. The THERIACA ANDROMACHI, Ph. L. 1746, contained above 60 ingredients. Mithridate and Venice treacle are examples of this class. See TREACLE.

=THERMOM′ETERS.= FAHRENHEIT’S scale is the one generally employed in England, while that of CELSIUS, or the CENTIGRADE scale, is principally used on the Continent. REAUMUR’S is another scale occasionally employed. DE LISLE’S thermometer was formerly used in Russia, and some other parts of the north of Europe. As references to these scales are frequently met with in books, it is useful to know their relative value, and the method of reducing the one to the other. The boiling point of water is indicated by 212° on Fahrenheit’s scale, 100° on the Centigrade scale, 80° on that of Reaumur, and O° on that of De Lisle; the freezing point of water marks 32° Fahrenheit, and 0°, or zero, on the Centigrade and Reaumur, and 150° on the scale of De Lisle. The 0°, or zero of Fahrenheit, is 32° below the freezing point of water.

1. To reduce Centigrade degrees to those of Fahrenheit, multiply them by 9, divide the product by 5, and to the quotient add 32; that is——

Cent.° × 9 / 5 + 32 = Fahr.°

2. To reduce Fahrenheit’s degrees to Centigrade:

(Fahr.° - 32) × 5 / 9 = Cent.°

3. To reduce Reaumur’s to Fahrenheit’s:

Reau.° × 9 / 4 + 32 = Fahr.°

4. To convert Fahrenheit’s to Reaumur’s:——

(Fahr.° - 32) × 4 / 9 = Reaumur.°

Thermometers intended to register extreme degrees of heat are called PYROMETERS (which _see_)

=THIBANT’S BALSAM.= FOR WOUNDS. Digest flowers of St John’s wort, one handful in 1/2 pint of rectified spirit; then express the liquor, and dissolve in it myrrh, aloes, and dragon’s blood, of each 1 dr., with Canada balsam, 1/2 oz.

=THO′RIUM.= Th. _Syn._ THORINUM. A very rare element, belonging to the group of earthy metals. Metallic base of thoria. It is obtained by the action of potassium on the chloride of thorium, and washing the resulting mass in water.

=THORN-APPLE.= See DATURA.

=THROAT AFFECTIONS.= We intend here only to allude to those arising from exposure or cold. The list is, therefore, a short one. CROUP, one of the most important, has been already briefly noticed.

QUINSY, or INFLAMMATORY SORE THROAT, commonly commences with stiffness and pain on one side of the throat, and swelling of the tonsils, attended by febrile symptoms, which increase as tumefaction advances, and sometimes become extreme. There is great restlessness and anxiety, considerable difficulty in swallowing even liquids, the respiration is painful and laborious, and the speech obstructed. When the inflammation is not resolved, these symptoms rapidly increase in severity, the patient suffers the greatest misery, the tumour suppurates rapidly, the abscess bursts, and with the rupture comes almost immediate relief. It occasionally happens that the other side of the throat then becomes affected, and goes through the same stages; but in general this is not the case, and the patient rapidly recovers, a few detergent gargles and a light nutritious diet being all that is required. Sometimes, at the very commencement of the attack, the inflammation may be resolved by the patient sucking a lozenge or powder, every hour or two, containing 1/4 or 1/2 grain of tartarised antimony carefully triturated with about 20 gr. of lump sugar, so as to keep up a constant state of nausea or vomiting for hours.

MALIGNANT SORE THROAT is marked by the inflammation of the tonsils being more superficial; but no sooner does it occur than it passes into small ulcers of varied colours and appearance, extending to the pharynx, and spreading over the whole fauces into the nostrils, and even around the glottis and down the œsophagus. These ulcers rapidly slough, and the febrile symptoms of a typhoid character, which are present throughout, become more or less severe. In this way the disease often hastens to a fatal termination, and, being highly contagious, often extends itself to all, or nearly all, the members of a family. The treatment must be similar to that adopted for typhus fever. Stimulating gargles, containing capsicum, the mineral acids, or port wine, are useful local remedies. See DIPHTHERIA.

=THRUSH.= _Syn._ APHTHA, L. A disease of infancy, which, in its common form, is marked by small white ulcers upon the tongue, palate, and gums. In some cases it extends through the whole course of the alimentary canal, and, assuming a malignant form, proves fatal. The treatment consists of a gentle emetic of ipecacuanha wine, followed by an occasional dose of rhubarb and magnesia, to keep the bowels clear, and to arrest diarrhœa. The ulcerations may be touched with a little honey or borax; and if they assume a dark colour, or there be much debility, astringents and tonics should be had recourse to. In all cases the diet should be light, but supporting, as imperfect nutrition is a common cause of the disease.

_In Animals._ Topical applications of alum or borax, glycerine, Condy’s fluid; laxatives. The food should be cooling and digestible.

=THYMOL.= _Syn._ THYMIC ACID, C_{10}H_{14}O. This substance is the oxygenated constituent of the essential oils of thyme (_Thymus vulgaris_), horse mint (_Monarda punctata_), and (_Ptychotis ajowan_) a common umbelliferous plant growing in India. Thymol is isomeric with cymilic alcohol, and homologous with phenyl.

Thymol may be procured from either of the above sources by treatment with caustic potash or soda, as described below, or by submitting the essential oils to a low temperature for some days. When prepared by the first process thymol occurs as an oily fluid; and when by the second, as a crystalline solid.

The following are the details of the preparation of the liquid variety of thymol as given by the Paris Pharmaceutical Society in their formulæ for new remedies published in 1877:——

“Treat essential oil of thyme with an equal volume of an aqueous solution of potash or soda, and shake several times to facilitate combination. The thymol dissolves, forming a soluble compound, whilst the thymene, a carbide of hydrogen, that accompanies it in the essence, does not combine with the alkali and separates. Filter the solution obtained and treat with an acid——hydrochloric acid, for example——which sets free the thymol. The product should be purified by washing, dried, and distilled. Thymol was obtained in fine tubular crystals by Flückiger and Hanbury, who exposed oil of ajowan to a temperature of 0° C.; the oil so treated yielded 35 per cent. of its weight of crystallised thymol. Mr Gerrard says it is stated that oil of thyme yields as much as 50 per cent.

“As found in commerce, thymol consists of irregular broken crystals, nearly transparent and colourless; the taste is burning and aromatic, sp. gr. 1·028, but lighter than water when fused; its melting point is about 44° C. When once completely fused and allowed to cool to the ordinary temperature, it will maintain itself in the fluid condition for several days, but the contact of a crystal will at once cause it to crystallise. It is freely soluble in alcohol, ether, chloroform, benzol, carbon bisulphide, fats, and oils, and but sparingly in water and glycerin. The alkaline hydrates of potash and soda are powerful solvents of thymol; ammonia dissolves it but sparingly.

“The potash and soda solutions are spoken of by some authors as chemical combinations; but the following test will demonstrate them otherwise. When shaken with ether the thymol can be entirely removed, and obtained as a neutral volatile residue.”[232]

[Footnote 232: “Thymol and its Pharmacy,” by A. W. Gerrard, F.C.S., ‘Ph. Journ.,’ vol. viii, 3rd series, 645.]

With sulphuric acid thymol forms crystallisable colugated acid, the thymol sulphuric having the formula HC_{10}H_{13}SO_{4}. Undiluted thymol is an energetic caustic. According to Bucholz, thymol possesses ten times the septic power of carbolic acid, over which it also has the advantage of being non-poisonous, and of giving off an agreeable odour. Although considerably dearer than carbolic acid, the much smaller quantity required to produce an equivalent effect nearly equalises it in point of cost. It is said to have been successfully employed in the antiseptic treatment of wounds in destroying the fœtor arising from ulcerated surfaces and carious bones; in the form of spray during surgical applications, as well as for certain throat affections, and as an ointment and lotion in psoriasis and other skin diseases. When thymol is to be used for lotions, injections, inhalations, or spray solutions, the Paris Pharmaceutical Society recommends 1 part of thymol to be dissolved in 4 parts of alcohol at 90°, and this to be added to 995 parts of distilled water.

Dr Crocker, of University College Hospital, strongly recommends thymol lotion to be prepared with glycerin, which, he says, obviates the drying effect upon the skin produced by aqueous or spirituous solutions of the thymol alone. According to Mr Gerrard, this lotion is prepared by dissolving 1 part of thymol in 120 parts of glycerin, and reducing by water to 600 parts. Dr Symes says he finds milk to be an excellent solvent for thymol, of which it will take up readily to nearly 10 per cent. of its weight. In cases, therefore, in which solutions are required of greater strength than aqueous ones, he recommends the employment of the fluid.

An ointment varying in strength from 1 to 5 parts of thymol to 100 of lard, is said by Mr Gerrard to be employed in our hospitals. In the preparation of this ointment, it is of importance to first dissolve the thymol in a few drops of spirits, and then to mix it with the lard. The neglect of this precaution causes the undissolved particles of thymol present in the ointment to act as a caustic irritant on the skin, and to eat little holes in it. Mr Gerrard found vaseline an unsuitable and objectionable vehicle for the application of thymol, since, after a few days, an ointment prepared with it had its surface covered with minute crystals of thymol.

The ‘Medical Times’ contains the following formula for the preparation of thymol gauze for dressing wounds:——“Bleached gauze, 1000 parts; spermaceti, 500; resin, 50; thymol, 16 parts.” This is said to yield an extremely soft and pliant preparation, excellently adapted for wounds, fitting accurately to them, and absorbing at the same time the blood and secretions from them like a sponge would do. Dr Ranke has pointed out that, in consequence of the great reduction in the amount of secretion from wounds caused by the use of thymol, the consequent consumption of bandages becomes so much less as to more than compensate for the great difference in price between thymol and carbolic acid.

Another advantage possessed by thymol over carbolic acid is that the redness, vesication, and eczema, frequently induced when dressings of the latter agent are used, does not follow the application of thymol dressings.

Mr Squire prepares an antiseptic adhesive plaster, containing 1 part of thymol to a 1000 of plaster.

Mr Gerrard in operating upon nine different samples of commercial oil of thyme (so-called oil of origanum) by means both of caustic soda and refrigeration, states, that except in one doubtful case, he was unable to obtain the slightest trace of thymol. From this circumstance Mr Gerrard infers that thymol is not present in the English oils of thyme of commerce, from which it must have been removed in the countries where it is produced, the residual cymene and thymene being sent us is an oil of thyme.

Large quantities of thymol are prepared in Germany, principally from the seeds of the _Ptychotis ajowan_. One firm of chemical manufacturers residing in Leipzig is reported to have sent out during the months of September and November last year more than a ton of it. Thymol wadding is also in extensive demand.

=TIC DOULOUREUX′.= [Fr.] According to a writer in one of the medical periodicals, a solution of atropia, 2 gr., in water, 1 fl. dr., to which nitric acid, 1 drop (minim), has been previously added, applied as a paint, by means of a camel-hair pencil, to the part of the face over the spot affected, immediately and completely subdues the pain, or, at all events, within 3 to 5 minutes, in all accidental cases, and affords considerable relief in others. The application is to be continued until some relief is experienced. The solution, being very poisonous, must not be taken internally, nor applied to the skin when broken. See ATROPIA and NEURALGIA.

=TIN.= Sn. _Syn._ STANNUM (Ph. E. & D.), L. This metal has been known from the most remote antiquity, being mentioned in the books of Moses (Numb. xxxi, 22), and by Homer (‘Iliad,’ x, 25), and other early writers. The ancients obtained it principally, if not solely, from Cornwall. The Phœnicians traded with England for this metal at least 1000 years before the birth of Christ.

Tin occurs in nature in the state of oxide, and, more rarely, as sulphide (TIN PYRITES). In Cornwall it is found under the form of peroxide (MINE-TIN, TIN-STONE), associated with copper ore, in the slate and granite rocks, and as an alluvial deposit (STREAM-TIN) in the beds of rivers.

_Prep., &c._ The ore is first reduced to powder in stamping-mills, washed to remove earthy matter, and then roasted to expel arsenic and sulphur; it is next deoxidised or reduced by smelting it with about 1-6th of its weight of powdered culm, and a little slaked lime; it is, lastly, refined by ‘liquation,’ followed by a second smelting of the purer portion, which, after being treated in a state of fusion, for some time with billets of green wood, or ‘tossed,’ as the workmen call it, is allowed to settle, and is then cast into large blocks, which, after being assayed, receive the stamp of the duchy. Two varieties of commercial tin are known, called respectively grain tin and bar tin. The first is the best, and is prepared from the stream ore.

_Prop._ Tin approaches silver in whiteness and lustre; in hardness it is intermediate between gold and lead; it is very malleable when pure, but the presence of a very small quantity of any other metal, particularly lead, deprives it of this property; when rubbed it evolves a peculiar odour, and when bent backwards and forwards it emits a peculiar crackling noise; it melts at 442° Fahr.; volatilises at a white heat; and when heated above its melting-point, with free access of air, is speedily converted into a yellowish-white powder, which is the peroxide, or the ‘putty powder’ of polishers. Sp. gr. 7·29 to 7·31.

_Pur._ It is almost entirely dissolved by hydrochloric acid, yielding a colourless solution; the precipitate thrown down by hydrate of potassium is white, and soluble in excess of the precipitant. If it contain arsenic, brownish-black flocks will be separated during the solution, and arseniuretted hydrogen evolved, which may be inflamed and tested in the usual manner. The presence of other metals in tin may be detected by treating the hydrochloric solution with nitric acid, sp. gr. 1·16, first in the cold, and afterwards with heat, until all the tin is thrown down in the state of insoluble stannic oxide. The decanted acid solution from pure tin leaves no residuum on evaporation. If, after all the acid has been dissipated by heat, dilution with water occasion a heavy white precipitate, the sample contained bismuth; if, after dilution, a solution of sulphate of ammonium or of sodium produce a similar white precipitate (sulphate of lead), it contained lead; if ammonia, added in excess, occasion reddish-brown flocks, or if ferricyanide of potassium give a blue precipitate, it contained iron; and, if the clear supernatant liquid leave a residuum on evaporation, copper.

_Tests._ The stannous salts are characterised as follows:——1. Hydrate of potassium gives a bulky white precipitate, readily soluble in excess of the precipitant; on concentrating the solution, the precipitate is changed from stannous hydrate into stannic hydrate, which remains in solution, and metallic tin, which separates in brown flakes.——2. Ammonia, and the carbonates of potassium, sodium, and ammonium, give white precipitates, insoluble in excess.——3. Sulphuretted hydrogen gives, in neutral and acid solutions, a dark brown precipitate, which is soluble in hydrate of potassium, in the alkaline sulphides (especially when they contain an excess of sulphur), and in strong hot hydrochloric acid; and insoluble in nitric acid, even when boiling.——4. Sulphide of ammonium produces a like brown precipitate, soluble in excess of the precipitant, provided the latter contains an excess of sulphur.——5. Terchloride of gold gives, in the cold, on the addition of a little nitric acid, a precipitate of the purple of Cassius.——6. Mercuric chloride gives a black precipitate, but in excess it produces a white one.

=Stannous Chloride.= SnCl_{2}. _Syn._ PROTOCHLORIDE OF TIN. _Prep._ (ANHYDROUS.) Distil a mixture of tin and mercuric chloride. Grey, resin-like, solid, fusible, and volatile.

(HYDRATED; TIN SALT.) Boil an excess of tin in hydrochloric acid. A powerful deoxidising agent. It is somewhat extensively used as a mordant in dyeing.

=Stannous Hydrate.= Sn(HO)_{2}. _Syn._ HYDRATED OXIDE OF TIN. _Prep._ Precipitate stannous chloride with carbonate of potassium, well wash, and dry under 196°. Greyish-white powder, soluble in acids and alkaline hydrates, except ammonia.

=Stannous Iodide.= SnI_{2}. _Syn._ PROTIODIDE OF TIN. Heat tin and iodine together. A fusible brownish-red, translucent substance, soluble in water.

=Stannous Oxide.= SnO. _Syn._ PROTOXIDE OF TIN. _Prep._ Ignite the hydrate in an atmosphere of carbonic anhydride. Black powder, inflammable in air, and insoluble in acids.

=Stannous Sulphide.= SnS. _Syn._ PROTOSULPHIDE OF TIN. A brittle bluish-grey substance, obtained by heating tin and sulphur.

The stannous salts behave with reagents as follows:——1. Hydrate of potassium, ammonia and alkaline carbonates, give a white precipitate, which is freely soluble in an excess of hydrate of potassium and in acids, sparingly soluble in excess of ammonia, only very slightly soluble in excess of carbonate of potassium, and insoluble in excess of carbonate of ammonium.——2. Sulphuretted hydrogen gives, in acid neutral solutions, a golden-yellow precipitate, either at once or on heating the liquid, which is readily soluble in pure hydrate of potassium, the alkaline sulphides, and boiling hydrochloric acid; less soluble in ammonia, and insoluble in nitric acid.——3. A plate of metallic zinc throws down metallic tin, under the form of grey scales or a spongy mass, from solutions free from nitric acid; and from those containing free nitric acid, white stannic hydrate.——4. Mercuric chloride gives a white precipitate.——5. Ferrocyanide of potassium gives no precipitate at first, but after a time the whole forms a thick jelly.

_Assay._ Each grain of stannic oxide (see _above_), after being washed and gently ignited, is equivalent to ·78365 gr. of pure tin. The loss of weight represents the impurities. Each gr. of sulphate of lead, so treated, is equiv. to ·683 gr. of metallic lead (nearly).

_Uses._ The uses of tin in the arts are well known. In medicine, 1 to 3 dr. of the filings or powder, made into an electuary with treacle, are sometimes given in tapeworm, for 2 or 3 successive mornings, followed by an aperient.

=Stannic Chloride.= SnCl_{4}. _Syn._ BICHLORIDE OF TIN, TETRACHLORIDE OF TIN, PERCHLORIDE OF TIN, PERMURIATE OF T.†; STANNI BICHLORIDUM, STANNI PERMURAS, L. _Prep._ 1. (Liebig.) By dissolving grain tin in a mixture of hydrochloric acid, 2 parts; nitric acid and water, of each 1 part (all by volume); observing to add the tin by degrees, and to allow one portion to dissolve before adding another, as without this precaution the action is apt to become violent, and stannic oxide of tin to be deposited.

2. (ANHYDROUS; LIBAVIUS’S FUMING LIQUOR.) By heating stannous chloride in chlorine gas; or, by distilling a mixture of powdered tin, 1 part, with corrosive sublimate, 3 parts (5 parts——Fownes). A very volatile, colourless, mobile liquid, which fumes in the air, and boils at 248° Fahr.; when mixed with 1-3rd of its weight of water, it solidifies to a crystalline mass.

_Obs._ Solution of stannic chloride is much used by dyers, under the names of ‘SPIRITS OF TIN,’ ‘DYERS’ SPIRITS,’ ‘TIN MORDANT,’ &c., the proportions of the ingredients and the state of dilution being various, according to circumstances or the caprice of the manufacturer. A process, which has been highly recommended, and which seems preferable to all others, is to prepare a simple solution of the stannous chloride, and to convert it into a solution of the stannic chloride, either by the addition of nitric acid and a gentle heat, or by passing chlorine through it. See TIN MORDANTS.

=Stannic Hydrate.= Sn(HO)_{4}. _Syn._ HYDRATED PEROXIDE OF TIN, STANNIC ACID. _Prep._ By adding hydrate of potassium or an alkaline carbonate to a solution of stannic chloride. Soluble in acids and pure alkalies. Its compound with the latter are sometimes called STANNATES.

=Stannic Iodide.= SnI_{4}. By dissolving stannic hydrate in hydriodic acid. Yellow, silky crystals.

=Stannic Oxide.= SnO_{2}. _Syn._ BINOXIDE OF TIN, PEROXIDE OF TIN. _Prep._ By the action of nitric acid on metallic tin, the resulting white powder being well washed with water; or, by heating metallic tin above its melting-point, in the air. Yellow; anhydrous; insoluble.

_Obs._ Frémy has given the name of METASTANNIC ACID to the oxide prepared by the action of nitric acid on metallic tin; the hydrate he calls STANNIC ACID. See POLISHERS’ PUTTY.

=Stannic Sulphide.= SnS_{2}. _Syn._ BISULPHIDE OF TIN, BRONZE POWDER, MOSAIC GOLD; AURUM MUSIVUM, AURUM MOSAICUM, STANNI BISULPHURETEM, L. _Prep._ 1. To pure tin, 12 oz., melted by a gentle heat, add of mercury, 6 oz.; to the powdered mass, when cold, add of chloride of ammonium, 6 oz.; flowers of sulphur, 7 oz; and after thorough admixture place the compound in a glass flask or matrass, and gradually heat it, imbedded in sand, to low redness, and continue the heat for several hours, or until white fumes cease to be disengaged; the ‘aurum musivum’ remains at the bottom of the vessel, under the form of soft and very brilliant gold-coloured flakes.

2. (Berzelius.) Stannic oxide and sulphur, of each 2 parts; chloride of ammonium, 1 part; mix, and expose it to a low red heat, in a glass or earthenware retort, until sulphurous fumes cease to be evolved.

Used as a metallic gold colour, or substitute for powdered gold, in bronzes, varnish work, sealing-wax, &c.

=TIN FI′LINGS.= See TIN POWDER (_below_).

=TINFOIL, Lead in.= Tinfoil very rarely consists of pure tin; generally it contains more or less lead. According to the recent analysis of August Vogel, who has examined a great number of samples from very different sources, it contains from 1 to 19 per cent. of lead. There are, however, specimens of tinfoil which contain so little lead that it hardly gives a reaction with the appropriate tests.

Since tinfoil is so much used for covering articles of diet, or of confectionery, or of perfumery, it was a matter of some interest to determine whether or not there was any danger of transference of lead from the wrapper to the contents. A number of experiments upon soap, chocolate, and different kinds of dry sugar, which had been enveloped in tinfoil very highly charged with lead, showed that there was no contamination with lead. Cheese, on the other hand, on account of its being moist, and being closely in contact with the foil, did take up lead.

Of course the lactic acid of the cheese would also favour the taking up of the metal. A point worthy of being recorded in connection with this matter is the rapid diminution of the lead toward the centre of the cheese. Often plenty of lead was found in the rind, and none a little way in the cheese.[233]

[Footnote 233: ‘Repertorium für Pharmacie,’ Von Buchnee.]

=TIN GLASS†.= See BISMUTH.

=TIN MOR′DANTS.= _Syn._ DYERS’ SPIRIT, SOLUTION OF TIN, SPIRIT OF T., NITROMURIATE OF T.† These, as noticed above, vary greatly in their composition and character.

_Prep._ 1. Take of aquafortis, 8 parts; sal ammoniac or common salt, 1 part; dissolve, and add, very gradually, of grain tin, 1 part; and, when dissolved, preserve it in stoppered bottles from the air. This is the common ‘SPIRIT OF TIN’ of the dyers.

2. (Berthollet.) Nitric acid, at 30° Baumé, 8 parts; sal ammoniac, 1 part; dissolve, then add by degrees, of tin, 1 part; and when dissolved, dilute the solution with 1-4th of its weight of water.

3. (Dambourney.) Hydrochloric acid, at 17° Baumé, 4 parts; nitric acid, at 30° Baumé, 1 part; mix, and add by degrees, of Molucca tin, 1 part.

4. (Hellot.) Nitric acid and water, of each 1 lb.; sal ammoniac, 1 oz.; nitre, 1/2 oz.; dissolve, then add, by degrees, of granulated tin, 2 oz.

5. (Poerner.) Nitric acid and water, of each 1 lb.; sal ammoniac, 1-1/2 oz.; dissolve, then add, by very slow degrees, of pure tin. beaten into ribands, 2 oz.

6. (Schoeffer.) Nitric acid and water, of each 2 lbs.; sal ammoniac, 2 oz.; pure tin, 4-1/2 oz.; as last. All the above are used chiefly for dyeing scarlet, more particularly with cochineal.

7. (LAC SPIRIT.) From grain tin, 1 lb, slowly dissolved in hydrochloric acid (sp. gr. 1·19), 20 lbs. Recommended as a solvent for lac dye. For use, 3/4 to 1 lb. of the liquid is digested on each lb. of the dye for 5 or 6 hours, before adding it to the dye bath.

8. Hydrochloric acid, 6-3/4 lbs.; aquafortis, 1/2 lb.; grain tin, gradually added, 1 lb. Recommended for lac dye.

=TIN-PLATE.= Iron-plate covered with a coating of tin, by dipping it into a bath of that metal.

=TIN POW′DER.= _Syn._ TIN FILINGS, TIN DUST; STANNI PULVIS (Ph. E & D.), L. _Prep._ 1. (Ph. E.) Melt grain tin in an iron vessel, pour it into an earthenware mortar heated a little above its melting-point, and triturate briskly as the metal cools; lastly, sift the product, and repeat the process with what remains in the sieve.

2. (Ph. D.) Melt grain-tin in a black-lead crucible, and, whilst it is cooling, stir it with a rod of iron until it is reduced to powder; let the finer particles be separated by means of a sieve, and when, after having been several times in succession shaken with distilled water, the decanted liquor appears quite clear, let the product be dried for use.

_Obs._ Powdered tin is also prepared by filing and rasping.——_Dose_, 2 to 4 dr., as a vermifuge. POLISHERS’ PUTTY, coloured with ivory black, is frequently substituted for this powder, and hence arises the ill effects that sometimes follow its use.

=TIN′NING.= _Proc._ 1. Plates or vessels of brass or copper, boiled with a solution of stannate of potassa, mixed with turnings of tin, become, in the course of a few minutes, covered with a firmly attached layer of pure tin.

2. A similar effect is produced by boiling the articles with tin filings and caustic alkali or cream of tartar.

_Obs._ By either of the above methods chemical vessels made of copper or brass may be easily and perfectly tinned.

3. The following method for tinning copper, brass, and iron in the cold, and without apparatus, is by F. Stolba.[234]

[Footnote 234: ‘The Pharmacist,’ iv, 86.]

The requisites for accomplishing this object are:——1st. The object to be coated with tin must be entirely free from oxide. It must be carefully cleaned and care be taken that no grease spots are left; it makes no difference whether the object be cleaned mechanically or chemically. 2nd. Zinc powder; the best is that prepared artificially by melting zinc, and pouring it into an iron mortar. It can be easily pulverised immediately after solidification; it should be about as fine as writing sand. 3rd. A solution of protochloride of tin containing 5 or 10 per cent., to which as much pulverised cream of tartar must be added as will go on to the point of a knife. The object to be tinned is moistened with the tinned solution, after which it is rubbed hard with the zinc powder. The tinning appears at once. The tin-salt is decomposed by the zinc, metallic tin being deposited. When the object tinned is polished brass or copper, it appears as beautiful as if silvered, and retains its lustre for a long time. 4th. (C. Paul.)[235] The zinc or iron articles are immersed in a mixture of 1 part sulphuric or nitric acid with 10 parts of water; a solution of copper sulphate or acetate is then slowly added. After the deposition of a thin layer of copper, the articles are removed, washed, moistened with a solution of 1 part ‘tin crystals,’ in 2 parts water and 2 parts hydrochloric acid, and then shaken up with a mixture of fine chalk and copper. Ammonium sulphate, which is prepared by dissolving 1 part of copper sulphate in 16 parts of water, and adding ammonia until a clear dark blue liquid is obtained.

[Footnote 235: Dingl. Polyt, J., ccviii, 47-49, ‘Journ. Chem. Soc.’]

The articles may now be tinned by immersion in a solution of 1 part of tin crystals with 3 parts white argol in water. Brass, copper, or nickel goods, also iron and zinc articles which have been copper-plated, may be silvered by treatment (after thorough cleansing), with a solution of 14 grams silver in 26 grams of nitric acid, to which is added a solution of 120 grams of potassium cyanide in 1 litre water, and also 28 grams of finely powdered chalk.

=TINS, To Clean.= All kinds of tins, moulds, measures, &c., may be cleaned by being well rubbed with a paste made of whiting and water. They should then be rubbed with a leather, and any dust remaining on them should be removed by means of a soft brush. Finally, they must be polished with another leather. Always let the inside of any vessel be cleaned first, since in cleaning the inside the outside always becomes soiled. For very dirty or greasy tins, grated bath-brick and water must be used.

=TINC′TURE.= _Syn._ TINCTURA, L.; TEINTURE, Fr. Tinctures (TINCTURÆ; ALCOOLÉS, ALCOOLATURES) are solutions of the active principles of bodies, obtained by digesting them in alcohol more or less dilute. ETHEREAL TINCTURES (TINCTURÆ ÆTHEREÆ; ETHÉROLÉS, ETHÉROLATURES) are similar solutions prepared with ether.

_Prep._ “Tinctures are usually prepared by reducing the solid ingredients to small fragments, coarse powder, or fine powder, macerating them for 7 days, or longer, in proof spirit or rectified spirit, straining the solution through linen or calico (or paper), and finally expressing the residuum strongly, to obtain what fluid is still retained in the mass. They are also advantageously prepared by the method of displacement or percolation.” (Ph. E.) “All tinctures should be prepared in closed glass (or stoneware) vessels, and be shaken frequently during the process of maceration.” (Ph. L.) Cooper’s patent jars are very convenient for the preparation of tinctures, as they are made with wide mouths large enough to admit the hand, and yet may be closed in an instant, with as much ease and certainty as an ordinary stoppered bottle.

Tinctures are better clarified by repose than by filtration, as in the latter case a considerable portion is retained by the filtering medium, and lost by evaporation. The waste in this way is never less than 10% of spirit. In all ordinary cases, it is sufficient to allow the tincture to settle for a few days, and then to pour off the clear supernatant portion through a funnel loosely choked with a piece of sponge or tow; after which the remaining foul portion of the liquid may be filtered through bibulous paper in a covered funnel. The filtration should be conducted as rapidly as possible, for the double purpose of lessening the amount lost by evaporation and the action of the air on the fluid. Tinctures which have been long exposed to the air frequently lose their transparency within a few days after being filtered, owing to the oxidisement and precipitation of some portion of the matter previously held in solution, a change which occurs even in stoppered bottles. Resinous and oily tinctures, as those of myrrh, tolu, and lavender (comp.), may be generally restored to their former brightness by the addition of a quantity of rectified spirit, equal to that which they have lost by evaporation; but many tinctures resist this mode of treatment, and require refiltering.

Ethereal tinctures are best prepared by percolation, and should be both made and kept in stoppered bottles.

Mr Umney says:——It must always be remembered that the quantity of spirit required to make the measure of tinctures to a given bulk, will only be strictly uniform, in so far as the operators proceed under precisely the same circumstances.

No causes will be found to influence results more than the manufacture of tinctures upon a small, as compared with a large, scale, and the use of the screw as compared with the hydraulic press, in the final removal of the spirit from the mare; even the temperature of summer and winter may cause a variation in the results.

_Qual._ The tinctures of the shops are usually very uncertain and inferior preparations, owing to their manufacture being carelessly conducted, and refuse drugs and an insufficient quantity of spirit being employed in their production. It is a general practice among the druggists to substitute a mixture of equal parts of rectified spirit and water, or a spirit of about 26 u. p., for proof spirit; and a mixture of 2 galls. of water with 5 galls. of rectified spirit, for rectified spirit. In some wholesale drug-houses all the simple tinctures (except those that are of a very active or valuable kind, as LAUDANUM, for instance) are made with 1 lb. of the dry ingredient to the gall. of spirit, irrespective of the instructions in the Pharmacopœia. Appearance is the object which is alone aimed at, without reference to quality. If the tincture be perfectly transparent, and has a good colour, the conscience of the seller and the stomach of the consumer are alike satisfied.

_Assay._ 1. The RICHNESS in ALCOHOL may be readily determined by Brande’s method of alcoholometry; but more accurately by the method of M. Gay-Lussac (see ALCOHOLOMETRY). That of tinctures containing simple extractive, saccharine, or like organic matter, in solution, may be approximately found from the boiling-point, or from the temperature of the vapour of the boiling liquid.

2. The QUANTITY of SOLID MATTER per cent. may be ascertained by evaporating to dryness 100 grains-measure, in a weighed capsule, by the heat of boiling water.

3. The QUANTITY of the INGREDIENTS used in the preparation of tinctures may be inferred from the weight last found, reference being had to the known per-centage of extract which the substances employed yield to spirit of the strength under examination. When the ingredients contain alkaloids, or consist of saline or mineral matter, an assay may be made for them.

_Uses, &c._ Tinctures, from the quantity of alcohol which they contain, are necessarily administered in small doses, unless in cases where stimulants are indicated. The most important and useful of them are those that contain very active ingredients, such as the tincture of opium, foxglove, hemlock, henbane, &c. In many instances the solvent, even in doses of a few fluid drachms, acts more powerfully on the living system than the principles it holds in solution; and, when continued for some time, produces the same deleterious effects as the habitual use of ardent spirits. When the action of a substance is the reverse of stimulant, it cannot with propriety be exhibited in this form, unless the dose be so small that the operation of the spirit cannot be taken into account, as with the narcotic tinctures. Hence, this class of remedies are in less frequent use than formerly.

The following list embraces all the formulæ of the tincturæ of the London, Edinburgh, Dublin, and British Pharmacopœias, with a few others likely to be useful to the reader. These will furnish examples for the preparation of others in less general use, care being had to proportionate the ingredients with due reference to the proper or usual dose of tinctures of that class.

=Tincture of Ac′etate of I′ron.= _Syn._ TINCTURA FERRI ACETATIS (B. P., Ph. D.), L. _Prep._ 1. (B. P.) Solution of persulphate of iron, 5; acetate of potash, 4; rectified spirit, q. s.; dissolve the acetate of potash in 20 of water and add 16 of spirit to the solution of iron; mix the two liquids, and shake well occasionally for an hour, then filter, and add to the filtered liquid sufficient rectified spirit to make up 40.——_Dose_, 5 to 30 minims.

2. (Ph. D.) To water, 9 fl. oz., add of pure sulphuric acid, 6 fl. dr.; and in the mixture, with the aid of a gentle heat, dissolve sulphate of iron, 8 oz.; next add of pure nitric acid, 1/2 fl. oz., previously diluted with water, 1 fl. oz., and evaporate the resulting solution to the consistence of a thick syrup; dissolve this in rectified spirit, 1 quart; also dissolve of acetate of potash, 8 oz., in another quart of rectified spirit; and having thoroughly mixed the solutions, by frequent agitation in a large bottle, filter the whole, with expression, first through calico, and then through paper. Sp. gr. ·891.——_Dose_, 15 to 60 drops, in water, in the same cases as in the other chalybeates.

=Tincture of Acetate of Zinc.= _Syn._ TINCTURA ZINCI ACETATIS, L. _Prep._ (Ph. D. 1826.) Acetate of potash and sulphate of zinc, of each 1 oz.; rub them together, then add of rectified spirit, 16 fl oz.; macerate for a week, and filter. Astringent. Diluted with water, it is used as a collyrium and injection.

=Tincture of Ac′onite.= _Syn._ TINCTURA ACONITI (Ph. L.), TINCT. ACONITI RADICIS (B. P., Ph. D.), L. _Prep._ 1. (B. P.) Powdered root, 1; rectified spirit to percolate, 8; macerate for 48 hours with three fourths of the spirit, agitating occasionally, pack in a percolator and let it drain, then pour on the remaining spirit; when it ceases to drop, press the marc and add spirit to make up 8.——_Dose_, 5 to 15 minims, twice or thrice a day.

2. (Ph. L.) Take of aconite root, coarsely powdered, 15 oz. (20 oz.——Ph. D.); rectified spirit, 1 quart; macerate for 7 days, press, and filter.

_Obs._ These tinctures differ materially in strength.——_Dose._ Of the Ph. L., 5 to 10 drops; of the Ph. D., 3 to 6 drops, two or three times daily (carefully watching its effects); in rheumatism, gout, syphilis, &c., where a narcotic sedative is indicated. Diluted with water, it forms an excellent embrocation in rheumatism, neuralgia, &c. It should be applied by means of a small sponge, tied to the end of a stick or glass rod. The Ph. D. formula is nearly the same as that for Dr Turnbull’s concentrated tincture of aconite root, and that given by Dr Pereira. The TINCTURA ACONITI FOLIORUM of the Ph. U. S. is made with 1 oz. of the dried leaves to 8 fl. oz. of rectified spirit.

=Tincture of Aconite, Ethereal.= _Syn_. TINCTURA ACONITI ÆTHEREA. (P. Cod.) _Prep._ Powdered aconite, 4 oz.; sulphuric ether, 16 oz. (by weight). It is best prepared by percolation.

=Tincture of Ailanthus Bark.= _Syn._ TINCTURA AILANTHI CORTICIS. _Prep._ Take Of ailanthus bark, bruised, 1-1/2 oz.; proof spirit, 1 pint; macerate for seven days in a closed vessel with occasional agitation, then strain, press, filter, and add sufficient spirit to make 1 pint.——_Dose._ From 1/2 to 2 fl. dr.

=Tincture of Al′oes.= _Syn._ TINCTURA ALOËS (B. P., Ph. L. & E.), L. _Prep._ 1. (B. P.) Socotrine aloes, 1; extract of liquorice, 3; proof spirit, 40; macerate seven days, press, and wash the marc with spirit to make 40.——_Dose_, 1 to 2 dr.

2. (Ph. L.) Socotrine or hepatic aloes, coarsely powdered, 1 oz.; extract of liquorice, 3 oz.; water, 1-1/2 pint; rectified spirit, 1/2 pint; macerate for 7 days, and filter. The formula of the Ph. E. is nearly similar. Purgative and stomachic.——_Dose_, 1/4 to fl. oz.

=Tincture of Aloes, Alkaline.= _Syn._ TINCTURA ALOËS ALKALINA. (Swediaur.) _Prep._ Aloes, 1/2 oz.; extract of liquorice, 1-1/2 dr.; cinnamon water, 8 oz.; proof spirit, 8 oz.; carbonate of soda, 1 oz. Digest, and strain.——_Dose_, 1 dr. to 4 dr.

=Tincture of Aloes (Compound).= _Syn._ TINCTURE OF ALOES AND MYRRH; TINCTURA ALOËS COMPOSITA (Ph. L.), TINCTURA ALOËS ET MYRRHÆ (Ph. E.), ELIXIR ALOËS†, L. _Prep._ 1. (Ph. L. & E.) Socotrine or hepatic aloes, coarsely powdered, 4 oz.; hay saffron, 2 oz.; tincture of myrrh, 1 quart; macerate for 7 days, with occasional agitation, and strain. The Dublin College (1826) omits the saffron.

2. (Wholesale.) From aloes, 1 lb.; myrrh, 3/4 lb.; hay saffron, 2 oz.; rectified spirit, 5 pints; water, 3 pints; as the last. Purgative, stomachic, and emmenagogue.——_Dose_, 1/2 to 2 fl. dr.

=Tincture of Amber.= _Syn._ TINCTURA SUCCINI. (P. Cod.) _Prep._ Amber, in fine powder, 1 oz.; rectified spirit, 6 oz. Digest for 6 days and filter.——_Dose_, 20 to 30 drops.

=Tincture of Amber, Alkaline.= _Syn._ TINCTURA SUCCINI ALKALINA. (Ph. E. 1744.) _Prep._ Rub 2 oz. of amber with a sufficient quantity of carbonate of potash to form a soft paste; dry this, and digest it in 16 oz. of rectified spirit for 8 days.

=Tincture of Ambergris.= _Syn._ TINCTURA AMBERGRISEÆ. (P. Cod.) _Prep._ Ambergris, 1 part; rectified spirit, 10 parts. Macerate 10 days.

=Tincture of Ammo′′nia (Compound.)= _Syn._ TINCTURA AMMONIÆ COMPOSITA (Ph. L.), L. _Prep._ 1. (Ph. L.) Mastic, 2 dr.; rectified spirit, 9 fl. dr.; digest until dissolved, decant, add, of oil of lavender, 14 drops; stronger solution of ammonia, 1 pint; and mix well.

2. (Ph. L. 1836; AQUA LUCIÆ; EAU DE LUCE.) As the last, but adding 4 drops of oil of amber along with the oil of lavender.

_Obs._ This preparation is reputed antacid, antispasmodic, and stimulant.——_Dose_, 10 to 20 drops, in water; in hysteria, low spirits, &c. In the East Indies, eau de luce is regarded almost as a specific for the bite of the cobra di capello and other venomous reptiles.

=Tincture of Ammo′′nia-chlo′′ride of I′ron.= _Syn._ AMMONIATED TINCTURE OF IRON, MYNSIGHT’S A. T. OF I.; TINCTURA FERRI AMMONIO-CHLORIDI (Ph. L.). TINCTURA FERRI AMMONIATI, L. _Prep._ (Ph. L.) Ammonio-chloride of iron, 4 oz.; proof spirit and distilled water, of each 1 pint; dissolve.——_Dose_, 20 to 60 drops, or more; as a stimulant, chalybeate tonic. “A fl. oz. of this, on potassa being added, yields 5·8 gr. of sesquioxide of iron.” (Ph. L.)

=Tincture of Ammoniacum.= _Syn._ TINCTURA GUMMI AMMONIACI. (P. Cod.) _Prep._ Gum ammoniacum, 4 oz.; rectified spirit, 20 oz. (by weight). Digest 10 days, and strain.

=Tincture of Angelica.= _Syn._ TINCTURA ANGELICA. (Aust. Ph.) _Prep._ Dried angelica root, 1 oz.; proof spirit, 6 oz. Digest, and filter.——_Dose_, 1 dr.

=Tincture of Angostu′ra.= Tincture of cusparia.

=Tincture, Antiscorbutic.= _Syn._ TINCTURA ANTISCORBUTICA, TINCTURA ARMORACUE COMPOSITA. (P. Cod.) _Prep._ Fresh horseradish root, 8 oz.; black mustard seed, 4 oz.; muriate of ammonia, 2 oz.; proof spirit, 16 oz. (by weight); compound spirit of scurvy grass, 16 oz. (by weight). Macerate 10 days.

=Tincture of Ants.= _Syn._ TINCTURA FORMICARUM. (Ph. G.) _Prep._ Ants recently collected, cleaned, and bruised, 2 oz.; rectified spirit, 3 oz. (by weight). Digest 8 days.

=Tincture of Ar′nica.= _Syn._ TINCTURA ARNICAE, T. A. FLORUM, L. _Prep._ (Ph. Bor. and Hamb. Cod.) Flowers of _Arnica montana_, 1-1/2 oz.; spirit, sp. gr. ·900 (15-1/2 o. p.), 1 lb.; digest for 8 days, and strain, with expression.——_Dose_, 10 to 30 drops; in diarrhœa, dysentery, gout, rheumatism, paralysis, &c.

=Tincture of Arnica Root.= _Syn._ TINCTURA ARNICAE (B. P.), TINCTURA ARNICÆ RADICIS, L. _Prep._ 1. (B. P.) Bruised root, 1; rectified spirit to percolate, 20; macerate forty-eight hours with 15 of the spirit, agitating occasionally; pack in a percolator, and, when it ceases to drop, pour on the remaining spirit, let it drain, wash the marc, press, filter, and make up to 20——_Dose_, 1 to 2 dr.

2. From arnica root, 2 oz.; proof spirit, 1 pint; as the last.