Cooley's Cyclopaedia of Practical Receipts Volume I Part 203

=Emerald Green.= See GREEN PIGMENTS.

=EMERY= is an impure, amorphous, compact, and opaque variety of corundum, and consists of alumina, with a small per-centage of silica and peroxide of iron. It occurs in Spain, the isles of Greece, and other localities, and derives its name from Cape Emeri, in the island of Naxos. Its hardness is so great, that it scratches and wears down nearly all minerals except the diamond; hence the use of its powder for cutting and polishing gla.s.s and various other hard substances. For commercial purposes, the lumps of emery, as taken from the mine, are broken into pieces about the size of a hen's egg, which are then crushed under stampers, similar to those used for pounding metallic ores. The coa.r.s.e powder is then sifted through sieves covered with wire-cloth of different degrees of fineness, by which it is sorted into different sizes. In this state it forms the emery of the shops, or flour emery. For delicate purposes, it is afterwards prepared by elutriation.

=Emery Cakes= are formed by melting emery flour with a little beeswax, and after thorough admixture, forming it into solid lumps of suitable sizes.

Used to dress the edges of buff and glaze wheels.

=Emery Cloth= is prepared by brushing the surface of thin cotton cloth over with liquid glue, and sifting the emery powder over the surface while still warm.

=Emery Paper= is made in the same way as emery cloth. Both are used either with or without oil, in the same way as gla.s.s paper.

=Emery Sticks= are made of pieces of wood in the same way, and are used for the same purposes, as emery paper.

=Emery Stones= are formed of emery, of the requisite coa.r.s.eness, mixed with about half its weight of good Stourbridge loam, and water q. s. to make a stiff paste, which is forced into metallic moulds by a powerful press. The pieces, when thoroughly dry, are exposed in a m.u.f.fle for a short time to a temperature just under a full white heat. In this way 'discs' and 'laps' are generally made. For 'wheels,' only 1/4th of loam is used. Another method, applicable for 'cutting stones' generally, is to press the flour emery, previously moistened with water, into moulds, with strong pressure, as before, without any other addition, and then to fire it at nearly a full white heat.

=EMETIA.= _Syn._ EMETIN, EMETINA. A feebly basic or alkaloidal body, existing in and forming the active principle of ipecacuanha.

_Prep._ 1. (Medicinal--EMETIC EXTRACT.)--_a._ Ipecacuanha (in coa.r.s.e powder) is digested first in ether, and then in rectified spirit for 3 or 4 days; the alcoholic tincture is next expressed and evaporated (distilled) to dryness; the residuum is dissolved in distilled water, and the solution precipitated with acetate of lead; the precipitate is then diffused through distilled water, in a tall gla.s.s vessel, and sulphuretted hydrogen is pa.s.sed through it, to throw down the lead; after which the liquor is decanted, filtered, evaporated to the consistence of a thick syrup, and spread in a thin layer on warm plates of gla.s.s, and allowed to dry in a current of warm air, or by a gentle heat in a stove. The maceration in ether is frequently omitted.

_b._ Ipecacuanha, 1 part; rectified spirit (835), 7 parts; make a tincture, distil off the spirit, dissolve in cold distilled water, 5 parts; filter the solution, and evaporate, &c., as before. Inferior to the last.

_c._ (P. Cod.) As the last, nearly.

_Obs._ Medicinal or impure emetia is brownish, red, deliquescent, and emetic in doses of 1/4 to 1/2 gr.

2. (Pure.)--_a._ Ipecacuanha (in coa.r.s.e powder), 1 part, is digested for 24 hours in distilled water, 10 parts; together with calcined magnesia, added in slight excess; the deposit is then thrown on a filter, washed carefully with very cold water, and dried; it is next dissolved in rectified spirit and neutralised with dilute sulphuric acid; the filtered solution is decoloured with animal charcoal, again filtered, and again precipitated by digestion with magnesia; the last deposit forms a colourless solution with rectified spirit, which, by gentle evaporation, gives up its emetia as a yellowish white pulverulent ma.s.s, which may be rendered perfectly white by redissolving it in alcohol, &c., as before.

The process is rendered easier by first digesting the powdered ipecacuanha in ether.

_b._ (P. Cod.) Alcoholic extract of ipecacuanha, 1 part; water, 10 parts; dissolve, filter; add calcined magnesia, 1 part; evaporate to dryness, wash the product on a filter with very cold water, 5 parts; dry it again, and dissolve it in boiling alcohol; evaporate the filtered tincture to dryness, redissolve the residuum in a little water, acidulate (slightly) with dilute sulphuric acid, decolour with animal charcoal, filter, precipitate with liquor of ammonia, and dry the precipitate by a gentle heat.

_c._ (Ph. Suec. 1845.) Powdered ipecacuanha, 1 part; water, acidulated with sulphuric acid, 6 parts; digest, filter; add lime, 1 part, and evaporate to dryness over a water bath; the residuum is then exhausted with boiling rectified spirit, and otherwise treated as in the last formula.

_Prop., &c._ Pure emetia is white, pulverulent, inodorous, and bitter; fusible at 122 Fahr.; very soluble in alcohol and boiling water, but only slightly so in ether, oils, and cold water. It restores the blue colour of reddened litmus, and partially neutralises the acids, forming scarcely crystallisable salts. It is reddened by nitric acid, and this red colour is deepened by ammonia. Tincture of iodine produces a reddish precipitate in an alcoholic solution of emetia. With tincture of galls this solution behaves like morphia; but, unlike the last substance, the salts of iron produce no change of colour in it. These reactions, combined with its emetic properties, are sufficient for its identification.--_Dose._ White and pure emetia is emetic in doses of 1/20 to 1/16 gr. The large doses ordered in certain pharmaceutical compilations, evidently in error of the difference between the strengths of the pure and the impure or medicinal emetia, have, in several cases which have been reported on, produced very serious consequences.

The 'Journal de Pharmacie et de Chemie,' for September, 1875, contains a new process for the extraction of emetia, by M. A. Glenard. This process is based upon the combined use of lime and ether. It consists in treating with ether a suitably prepared powder, or an extract of ipecacuanha and lime, or the precipitate formed upon adding an excess of lime to a solution obtained by treating ipecacuanha in the cold with water acidulated by sulphuric acid. Either of these mixtures, or the precipitate, when treated with ether, will yield all the alkaloid it contains.

The alkaloid may be obtained from the ethereal solution by distilling it to dryness, and treating the residue with acidulated water, or by at once shaking the solution with acidulated water. A more or less acid aqueous liquid is thus obtained, which upon the addition of ammonia, yields the emetine almost colourless, and much more pure than that produced by the process ordinarily employed.

_Preparation of Crystallised Hydrochlorate and Pure Emetine._--When water, acidulated with hydrochloric acid, is employed to remove the emetine from the ether, an acid solution is obtained, which, when sufficiently concentrated by evaporation, forms a nearly colourless, solid, crystalline ma.s.s. This ma.s.s is formed of extremely delicate needles, formed in bundles that radiate around a central point, and form small spheres with an embossed surface, resembling mulberries in appearance. Upon pressing these crystals in a cloth the more or less coloured mother liquid runs off, and the crystals redissolved in water give a colourless solution, from which a fresh crystallisation of perfectly pure hydrochlorate of emetine can readily be obtained.

The production of this crystallised hydrochlorate of emetine is worthy of notice, since it does not accord with what has been stated by different authors, who have all considered emetine to be incapable of forming crystallisable salts. It is especially interesting in that it furnishes a convenient and certain method of obtaining perfectly pure emetine, for which it is only necessary to precipitate a solution of the hydrochlorate with an alkali. But it is important to observe that ammonia does not precipitate all the emetine of the hydrochlorate, and that the precipitate is less in proportion as the salt is more acid.

It might appear from this that emetine is soluble in hydrochlorate of ammonia. But the author finds that it is the result of a decomposing action exercised by the emetine upon the hydrochlorate of ammonia, as is shown by the following two experiments. If a little dry powdered emetine be placed in a gla.s.s containing a solution of hydrochlorate of ammonia, it may be observed to agglomerate and become transformed into a soft resinoid ma.s.s, at the same time the disengagement of ammonia may be recognised, and the resinoid ma.s.s gradually undergoes a kind of metamorphosis, and becomes white and crystalline. Again, if emetine in powder be suspended in water, and solution of hydrochlorate of ammonia be gradually added, the emetine is dissolved, and upon evaporation of the solution crystals of double hydrochlorate of emetine and ammonia is obtained.

The author believes the decomposition of hydrochlorate of ammonia by an organic alkali to have been hitherto un.o.bserved. It does not appear, however, that emetine is alone in this action, as the author has observed that quinine, under similar conditions, behaves in the same manner.

Zinoffsky ('Jour. de Pharm. d'Anvers,' xxix, 490) gives the following process for the quant.i.tative determination of emetia:--Treat fifteen grams of powdered ipecacuanha with alcohol of 85 per cent., acidified with a few drops of sulphuric acid, so as to form a volume of 150 cubic centimetres.

Filter, and after expelling the alcohol from 100 cubic centimetres of the liquid by distillation, add to the residue a t.i.trated solution of iodo-hydrargyrate of pota.s.sium until a filtered portion ceases to be affected by this reagent. The number of cubic centimetres of iodo-hydrargyrate multiplied by 00189 (00001 of the equivalent of emetine) gives the quant.i.ty of emetine contained in ten grains of the root.

A normal solution of iodo-hydrargyrate is obtained by mixing aqueous solutions of 13546 grams of bichloride of mercury, and 498 of iodide of pota.s.sium, adding water to make one litre. One cubic centimetre of this solution precipitates 00001, or 000005 of an equivalent of alkaloid.

Wine of ipecacuanha can be t.i.trated by the same process.

_Composition of Emetine and its Hydrochlorate._--These substances dried at 110 C., gave upon a.n.a.lysis results corresponding with following centesimal composition:

Hydrochlorate Emetine. of Emetine.

Carbon 7225 6300 Hydrogen 861 815 Nitrogen 536 475 Oxygen 1378 1164 Chlorine 1246

From these figures the author has constructed the following formulae:

Emetine: C_{30}H_{22}NO_{4}. Hydrochlorate of Emetine: C_{30}H_{22}NO_{4}HCl.

_Preparation and Composition of Emetine_ (J. Lefort and F. Wurtz, 'Comptes Rendus,' lx.x.xiv, 1299). When ipecacuanha is dissolved in water, and a concentrated solution of pota.s.sium nitrate added, a thick ma.s.s is produced, consisting of emetine nitrate. It is washed with water, dissolved in alcohol, and the solution poured into milk of lime. The mixture is evaporated to dryness, and digested with ether, which dissolves out the emetine, leaving it as a yellowish ma.s.s on evaporation. On dissolving this ma.s.s in sulphuric acid, and pouring the solution into dilute ammonia, the alkaloid is obtained as a white precipitate, which is dissolved in alcohol, from which it separates in minute radiate groups of needles. By a.n.a.lysis it gave numbers leading to the formula C_{28}H_{40}N_{2}O_{3}.[275]

[Footnote 275: Note by the translator ('Journal of Chem. Soc,'): "This is printed C_{28}N_{2}H_{40}O_{5} in the formula for emetine nitrate, and as no data are given, it is impossible to tell which are correct."]

Pure emetine nitrate was prepared, and was found to have the formula C_{28}N_{2}H_{40}O_{5}NOH; this in conjunction with Glenard's results, shows that emetine does not form basic salts.

=EMET'ICS.= _Syn._ VOMITS, ANACATHARTICS; ANACATHARTICA, EMETICA, VOMITORIA, L. Medicines which induce vomiting. The princ.i.p.al emetics are ipecacuanha and tartarised antimony, and their preparations; and the sulphates of zinc and copper. Of these the first is commonly employed either in substance or infused in wine (ipecacuanha wine), when it is merely wished to evacuate the contents of the stomach, when that organ is in a disordered state or overloaded with food; and is the one most adapted in ordinary cases for children and females. Tartar emetic (tartarated antimony) (dissolved in water) and antimonial wine, either alone or combined with ipecacuanha, are preferable at the commencement of fevers and other inflammatory disorders, in consequence of the nausea, relaxation, and depression of the muscular power and circulation which commonly follow their use. When poison has been taken, sulphate of zinc is generally preferred as an emetic, on account of the promptness and completeness of its action, and its effects ceasing as soon as it is ejected from the stomach. Sulphate of copper is employed in the same cases as sulphate of zinc, but its action is more violent and disagreeable, whilst its intense metallic taste is a great objection to its use. 25 to 30 gr. of either of the above sulphates are dissolved in 3 or 4 fl. oz. of warm water, and a fourth of the solution is given every ten minutes, until copious vomiting ensues. In the absence of other substances, when an immediate emetic is required, a teaspoonful of flour of mustard (an article always at hand), stirred up with half a pint of warm water, and drank at a draught, will generally act easily and effectively, and relieve the stomach before other remedies can be obtained and applied.

The operation of emetics is powerfully promoted by drinking copiously of diluents, especially of warm or tepid water. The latter, in fact, is itself an emetic, when taken in quant.i.ty. Its use will also prevent that dreadful straining and retching which makes emetics so much dreaded by the nervous and delicate.

The timely administration of an emetic at the commencement of fevers and other inflammatory affections will frequently cause copious diaph.o.r.esis, and produce a cure, or at least greatly mitigate the severity of the symptoms. Dropsies have also been cured by vomiting; and swelled t.e.s.t.i.c.l.e, bubo, and other glandular swellings, have occasionally been dispersed by the action of emetics. Visceral obstructions, in both s.e.xes, have also yielded to the same treatment. Small and repeated doses of emetics are frequently administered, with advantage, to produce nausea, in many diseases of the lungs and stomach. Certain chronic and obstinate diseases, as rheumatism and asthma, are sometimes relieved by emetics, when every other line of treatment has failed.

Emetics should be avoided in plethoric habits, in hernia, pregnancy, and whenever visceral inflammation is suspected. They should also be given with great caution to young children and females, and to the nervous and delicate. In such cases, wine or powder of ipecacuanha should alone be employed.

=Emetic Cups.= _Syn._ ANTIMONIAL CUPS; POCULA EMETICA, CALICES VOMITORII, L. Small cups made of metallic antimony. Wine left in them for 10 or 12 hours becomes emetic.

=Emetic Tartar.= See ANTIMONY, TARTARATED.

=EM'ETINE.= See EMETIA.

=EMMEN'AGOGUES.= _Syn._ EMMENAGOGA, L. Medicines which are considered to have the power of promoting the menstrual discharge when either retained or suspended. There are, probably, few remedies which exert this specific power on the uterus, the majority of repeated emmenagogues acting rather by their influence on the system generally, or on parts contiguous to the uterus, than in the uterus itself. Among the substances usually arranged under this cla.s.s are--aloes, black h.e.l.lebore, birthwort, borax, cubebs, ergot, gamboge, gin, iodide of pota.s.sium, iodine, madder, mercurials, the peppers, rue, savine, stimulants (generally), stimulating diuretics, stinking goosefoot, stinking orache, wine, &c.

Of the above, ergot and madder are the only articles which exercise a direct power on the uterus, and that rather in increasing its expulsive energy than in promoting the menstrual function, though they are advantageously employed for the latter purpose. Several of the other substances named are drastic purgatives, or possess cerebro-spinal properties, or local powers of irritation, by which they increase the pelvic circulation, or produce excitement in the neighbouring parts, in many cases of a dangerous and irreparable character. Hence many writers on pharmacology deny the existence of emmenagogues.

To ensure the successful administration of this cla.s.s of medicines, the system must be previously prepared for their use by invigorating it, if there is either relaxation or debility; and an opposite course should be pursued when there is an undue degree of arterial action. In the majority of cases, the restoration of the discharge is rather attributable to a proper regulation of the system than to any specific power in the medicine administered.

=EMOLL'IENTS.= _Syn._ EMOLLIENTIA, L. In _pharmacy_ and _therapeutics_, demulcents of an oleaginous, saponaceous, or emulsive character, applied to surfaces (generally external), to soften and relax the fibres. See DEMULCENTS.

=EMUL'SIN.= _Syn._ SYNAPTASE. An azotised substance, forming a large proportion of the white pulp of both bitter and sweet almonds. It is yellowish-white, soluble in cold water, and coagulated by heat and alcohol. Its most remarkable property is its action on amygdalin by which the volatile oil of almonds and hydrocyanic acid, with other products are formed. It has never been obtained in a state of purity.

=EMULSINES.= See EMULSION.

=EMUL'SION.= _Syn._ EMULSIO, L. A milky fluid, formed by the mechanical admixture of oil and water, by means of some other substance that possesses the power of combining with both. The emulsions of the Pharmacopia are in the 'British Pharmacopia' included in the cla.s.s _Misturae_ (which _see_).

In the preparation of emulsions, the oily or resinous ingredients are usually suspended by means of mucilage of gum arabic, almonds, or yolk of egg. 1 dr. of the first, made with equal parts of gum and water; 1 oz. of the second (usually 26 in number); and one in no. of the last, will form 2 dr. of any oil into an emulsion with about 1 oz. of water, gradually added. In some cases, instead of the above substances, a little liquor of pota.s.sa is employed, by which a saponaceous emulsion is formed. In all cases the mucilage or other viscid substance should be put into the mortar before anything else. The oil or resinous matter may then be very gradually rubbed in, taking care not to add it more quickly than it can be subdued by the pestle; and if, during this part of the manipulation, the mixture should begin to a.s.sume a breaking or curdling appearance at the edges, a few drops of water must be immediately incorporated with it, before adding the remainder of the oil. From the want of this precaution, it is common for an emulsion suddenly to lose its tenacious consistence in the mortar, and it is then in vain to endeavour to restore it. After the oil is thoroughly incorporated, some care is requisite to avoid separating it again by too hasty an effusion of the water or other fluid of the mixture. If any alcoholic or acid liquid is to be added, it must be at the very end of the process. Indeed, the addition of an acid liquid, even a slightly acescent syrup, will often entirely destroy an emulsion. Mixtures of copaiba are frequently spoiled by the addition of spirit of nitric ether; a misfortune which might be avoided by first diluting it with one or two parts of water.

An excellent method of preparing emulsions of resins and gum-resins, is to put the article into a marble or wedgwood mortar, and to pour over it about 4 times its weight of rectified spirit, which is then to be ignited, and the mixture triturated until an equal consistence is obtained. The liquid is then to be added gradually, and the whole patiently triturated or shaken until cold. Yolk of egg or mucilage may be added to the fluid resin or gum-resin, if desired, as in the common method, but an excellent emulsion may be made without them.