Cooley's Cyclopaedia of Practical Receipts Volume I Part 248

_c._ The bottom of the stone is coated with a film of real silver, by precipitating it from a solution of the nitrate in spirit of ammonia, by means of the oils of ca.s.sia and cloves.[318] This method vastly increases the brilliancy both of real and fact.i.tious gems, and the work is very permanent.

[Footnote 318: See SILVERING.]

2. (COLOURED FOILS.) The following formulae produce beautiful coloured effects, when judiciously employed:--

_a._ (Amethyst.) Lake and Prussian blue, finely ground in pale drying oil.

_b._ (Blue.) Prussian blue (preferably Turnbull's), ground with pale, quick-drying oil. Used to deepen the colour of sapphires.

_c._ (Eagle marine.) Verdigris tempered in sh.e.l.l-lac varnish (alcoholic), with a little Prussian blue.

_d._ (Garnet.) Dragon's blood dissolved in rectified spirit of wine.

_e._ (Vinegar garnet.) Orange lake finely tempered with sh.e.l.l-lac varnish.

_f._ (Green.)--a. From pale sh.e.l.l-lac, dissolved in alcohol (lacquer), and tinged green by dissolving verdigris or acetate of copper in it.

. From sesquiferrocyanide of iron and bichromate of pota.s.sa, of each 1/2 oz.; ground to an impalpable powder, first alone, and then with gum mastic (clean and also in fine powder), 2 oz.; a little pyroxilic spirit is next added, gradually, and the whole again ground until the ma.s.s becomes h.o.m.ogeneous and of a fine transparent green. The beauty increases with the length of the grinding. The predominance of the bichromate turns it on the yellowish green; that of the salt of iron on the bluish green. For use it is to be thinned with pyroxilic spirit. ('Chem.,' iii, 231.) Used for emeralds.

_g._ (Red.) Carmine, dissolved in spirit of hartshorn, or in a weak solution of salt of tartar, and a little gum (dissolved) added.

_h._ (Ruby.)--a. From lake or carmine, ground in isingla.s.s.

. Lake ground in sh.e.l.l-lac varnish. Both are used when the colour turns on the purple.

?. From bright lake ground in oil. Used when the colour turns on the scarlet or orange.

_i._ (Yellow.)--a. Various shades of yellow may be produced by tinging a weak alcoholic solution of sh.e.l.l-lac or mastic, by digesting turmeric, annotta, saffron, or socotrine aloes in it. The former is the brightest, and is used for topazes.

. From hay saffron digested in 5 or 6 times its weight of boiling water until the latter becomes sufficiently coloured, and a little solution of gum or isingla.s.s added to the filtered liquor. When dry, a coating of spirit varnish is applied.

_Obs._ By the skilful use of the above varnishes, good imitations of the gems may be cheaply made from transparent white gla.s.s or paste; and by applying them to foils set under coloured pastes (FACt.i.tIOUS GEMS), a superior effect may be produced. The pigments employed must be reduced to the finest state possible by patient grinding, as without this precaution transparent and beautiful shades cannot be formed. The palest and cleanest mastic and lac, dissolved in alcohol, and also the palest and quickest drying oil should alone be used when these substances are ordered. In every case the colour must be laid on the foil with a broad soft brush; and the operation should be performed, if possible, at once, as no part should be crossed, or twice gone over, whilst wet. If the colour turns out too pale, a second coat may be given when the first one has become quite dry, but this practice should be avoided if possible.

=FOMENTA'TION.= _Syn._ FOMENTATIO, FOMENTUM, FOTUS, L. A liquid, either simple or medicated, used for local bathing. Fomentations are distinguished from lotions chiefly in being applied in a heated state, and in larger quant.i.ties, and for a longer period at a time.

Fomentations are chiefly employed to allay pain or irritation, or to promote suppuration or the healthy action of the parts. As the intention is to convey heat, combined with moisture, to the part fomented, the utmost care must be taken to manage the application so as to promote the object in view as much as possible. Flannel cloths wrung out of the hot or boiling liquid, by means of two sticks, turned in opposite directions, form the best vehicles for fomentations. If they are shaken up, and laid lightly over the part, they involve a considerable quant.i.ty of air, which, being a bad conductor, retains the heat in them for a considerable time.

"In every process of fomenting there should be two flannels, each (say) three yards long, with the ends sewed together, to admit of the boiling water being wrung out of them; and the one flannel should be got ready whilst the other is applied. The fineness or the coa.r.s.eness of the flannel is not a matter of indifference. The coa.r.s.er it is the less readily does it conduct heat, and the longer it retains its warmth; therefore it is more efficient for fomenting. White flannel also retains the heat longer than coloured flannel." (Dr R. E. Griffith.) More harm than good is frequently done by allowing the patient to become chilled during the application. "If only one (flannel) is used, the skin becomes chilled during the time occupied in removing the flannel, soaking it in the water, wringing it out, and reapplying it; but if two are used, one of them is ready, and can be applied the moment the other is taken off, by which means the part is never exposed to the air, no matter how long the fomentation is continued. In some diseases (rheumatism, peritonitis, &c.), the patient is scarcely conscious of a degree of heat which scalds the nurse's hands. In this case the fomenting flannels should be put in a towel, by which means they may be wrung out without being handled by the nurse, and may be applied far hotter than can be done by any other method." (Dr J. B. Nevins.)

The quant.i.ty of liquid forming a fomentation, as well as the size of the cloths employed, must entirely depend upon circ.u.mstances. In some cases (as in slight affections of the face, &c.) the application may be effectually made by holding the part in the steam of the hot liquid, and bathing it continually by means of a sponge or cloth. In some instances 1/2 pint to a pint of liquid may be found a sufficient quant.i.ty; whilst in others several quarts will be required. Under all circ.u.mstances, care must be taken to keep the fomentation as near as possible at the temperature ordered, during the whole time of its application; and, as soon as the operation is finished, to quickly wipe the part dry, and to cover it with ample clothing, in order that the reaction set up may not be prematurely checked.

Fomentations usually consist of simple water, or the decoction of some simple vegetable substance, as chamomiles, elder flowers or mallows; but, occasionally, the leaves and flowers of aromatic and narcotic plants, and saline matter, are employed under this form. The following formulae are given as examples:--

=Fomentation, Acetic.= _Syn._ FOTUS ACETICUS (Paris Codex). Fomentations of vinegar are sometimes prepared with white, with rose, or with aromatic vinegar (Paris Codex) in the proportion of one of vinegar to four of water.

=Fomentation, An'odyne.= _Syn._ FOTUS ANODYNUS, FOMENTATIO ANODYNA, FOMENTUM ANODYNUM, L. _Prep._ 1. Simple decoction of poppy-heads.

2. (Hosp. F.) Poppy-heads (without the seeds), 1-1/2 oz.; water, 3-1/2 pints; boil to 2-1/2 pints; add of elder flowers, 3/4 oz.; boil to a quart and strain. Used to allay pain.

3. (Pierquin.) Opium, 1 oz.; wine, 1 quart; boil to a pint and strain.

Used in severe gouty, rheumatic, neuralgic, and syphilitic pains.

4. Opium, 1 oz.; water, 1 quart; boil to 3/4 pint, add pyroligneous acid, 2 fl. oz.; boil for 10 minutes longer, then further add of sherry wine, 3/4 pint; and as soon as the whole again boils, strain it for use.

Superior to the last, and cheaper.

=Fomentation, Antineural'gic.= _Syn._ FOMENTATIO ANTINEURALGICA, L.

_Prep._ 1. (Mialhe.) Acetate of morphia, 2 gr.; acetic acid, 2 or 3 drops; eau de Cologne, 2 or 3 dr.; dissolve. In facial neuralgia.

2. (Trousseau and Reveil.) Cyanide of pota.s.sium, 1 dr.; distilled water, 6 fl. oz.; dissolve and keep it in a well-closed bottle in the dark. Used in neuralgia, especially in that of the face (tic douloureux). A compress of lint or soft linen is dipped in it and applied to the part. It must not be used internally or applied to a wounded surface, as it is very poisonous.

See FOMENTATIONS, ANODYNE, Nos. 3 and 4 (above), also FOMENTATION, STIMULANT.

=Fomentation, Antiseptic.= _Syn._ FOMENTATIO ANTISEPTICA, L. _Prep._ 1.

Decoction of mallows, 4 pints; sal ammoniac, 2 oz.; dissolve, and add of disulphate of quinine, 20 gr., dissolved in camphorated spirit, 4 fl. oz.

2. (Hosp. F.) Decoction of bark, 1 quart; infusion of chamomile, 1 pint; camphorated spirit, 2 fl. oz.; hydrochloric acid, 1 fl. dr. Both are used when there is a tendency to gangrene or putrescence.

=Fomentation of Ar'nica.= _Syn._ FOMENTATIO ARNICae, L. _Prep._ 1. Flowers of arnica, 1 oz.; water, 3 pints; boil to a quart, and strain. Used in contusions.

2. (Graefe.) Flowers of arnica, 2 oz.; rue (leaves), 1 oz.; boiling water, q. s. to strain 12 fl. oz. of infusion after an hour's maceration at nearly the boiling temperature. Used in contusions and extravasations, especially as an application to black eyes.

3. (Radius.) Flowers of arnica, 1/2 oz.; boiling vinegar, q. s. to strain 6 fl. oz. of infusion, in which dissolve of carbonate of ammonia, 2 dr.

Used in dema of the s.c.r.o.t.u.m.

=Fomentation, Aromat'ic.= _Syn._ FOMENTATIO AROMATICA, FOTUS AROMATICUS, L. _Prep._ 1. Sea wormwood, southernwood, and chamomiles, of each 1 oz.; laurel leaves, 1/2 oz.; water 5 pints; boil to half gall., and strain. In rheumatism, cutaneous affections, colic, &c.

2. (Augustin.) Rosemary, 1/2 oz.; red wine, and water, of each 3 fl. oz.; infuse and strain with expression. In contusions, especially black eyes.

3. (Hosp. F.) Cloves and mace, of each 1 oz.; opium, 20 gr.; red wine (boiling), 1 pint; digest at near boiling for 1 hour, and strain. Used as both the last.

4. (Rideau.) Bay leaves, rosemary, southernwood, and wormwood, of each 1 oz.; water, 2 quarts; boil 5 minutes, and strain. As No. 1.

=Fomentation, Astrin'gent.= _Syn._ FOTUS ASTRINGENS, F. ROBORANS, L.

_Prep._ 1. Decoction of oak bark.

2. To each quart of the last add of alum 1 dr.

3. (Ph. Chirur.) Bruised galls, 1 oz.; boiling water, 2-1/2 pints; digest 1 hour, and strain.

4. (Ricord.) Tannin, 2-1/2 dr.; aromatic wine (hot), 1/2 pint; dissolve.

5. Bistort and pomegranate peel, of each 2 oz.; sal ammonia, 1/4 oz.; red wine, 1 pint.; infuse at a gentle heat. The above are used in haemorrhages, piles, prolapsus, &c.

=Fomentation of Belladon'na.= _Syn._ FOTUS BELLADONNae, L. _Prep._ (Ophthalmic Hosp.) Extract of belladonna, 1 dr.; boiling water, 1 pint.

Used to dilate the pupil in certain affections of the eye; it is usually applied on the forehead.

=Fomentation of Bitter-sweet.= _Syn._ DECOCTUM DULCAMARae, L. _Prep._ Bitter-sweet stalks, 10 dr.; water, 1-1/2 pint; boil to a pint, and strain.

=Fomentation of Cham'omile.= _Syn._ FOMENTATIO ANTHEMIDIS, L. _Prep._ Chamomiles, 2 oz.; water, 3 pints; boil 10 minutes, and strain with expression. Emollient.