A Cyclopædia of Practical Receipts, Processes, and Collateral Information (part 14)

c. (Ph. U. S. Extractum Sarsaparillæ Compositum fluidum.) Prep. Sarsaparilla in moderately fine powder, 16 oz. (troy); liquorice root in moderately fine powder, 2 oz. (troy); sassafras in moderately fine powder, 2 oz. (troy); mezereon in moderately fine powder, 360 grains; glycerin, 4 oz. (old measure); rectified spirit, 8 oz. (old measure); water, 4 oz. (old measure). Macerate in a closed percolator for 4 days, and then let the percolation commence, and finish it by adding diluted alcohol (equal volumes of alcohol at ·835, and water), until 2 pints (old measure) have been obtained. Reserve the first 12 oz., having added 4 oz. (old measure) of glycerin to the remainder of the percolate, which evaporate to 6 oz. (old measure), and mix with the reserved portion.

6. (From the root-bark; Extractum corticis sarzæ, L.) From the decoction or tincture of the root-bark. The cortical portion of sarsaparilla yields fully 50% of aqueous extract. “Five times as much as the meditullium.” (Pope.)

Obs. Each of the above extracts of sarsaparilla (simple, fluid, and compound), when of good quality, dissolves in water, forming a deep reddish-brown solution, perfectly transparent, and depositing little sediment, even by standing some days. See Sarsaparilla.

1. Extract of Savine. Syn. Extractum Sabinæ. (Ph. L. 1788.) By evaporating a decoction of dry savine.

2. (Ph. U. S. Extractum Sabinæ fluidum.) As fluid extract of cubebs. (Ph. U. S.)

Extract of Scam′mony. Syn. Resin of scammony; Resina Scammonii, E. s. alcoholicum, E. sive resina scammonii (Ph. E.), L. Prep. 1. From powdered scammony, exhausted with proof spirit, and the resulting tincture distilled until little but water passes over; the remaining water is then poured from the resin, which is next well washed in boiling water and dried at a temperature below 240° Fahr. Brown; impure.

2. As the last, but using either alcohol of 90% or ether, and animal charcoal. White; pure.

Obs. Scammony resin is translucent, fusible, and combustible; and freely soluble in alcohol, ether, and oil of turpentine. It is frequently adulterated with jalap resin, a fraud readily detected by its insolubility in the last two menstrua.—Dose, 5 to 10 gr. “When pure or virgin scammony can be procured it is an unnecessary preparation.” (Pereira.)

Extract of Scurvy-grass. Syn. Extractum cochleariæ, L. Prep. (P. Cod.) From the clarified juice of fresh scurvy-grass, by exposure to warm air. Anti-scorbutic, stimulant, anti-rheumatic, and diaphoretic.—Dose, 1 to 2 dr. The valuable principles of the juice are dissipated by much heat.

Extract of Sen′ega. Syn. Extractum senegæ, L. Prep. 1. (P. Cod.) From seneka or snake-root (Polygala Senega), as EXTRACT OF BOX—P. Cod.

2. Compound; Extractum senegæ, COMPOSITUM, E. s. et scillæ, L.—Ecky.) From equal parts of squills and senega, as the last, but by displacement. Both the above are stimulant, expectorant, sudorific, and diuretic.—Dose, 1 to 12 gr.

3. (Ph. U. S. Extractum senegæ fluidum.) As EXTRACT OF COTTON-ROOT. (Ph. U. S.)

Extract of Sen′na. Syn. Extractum sennæ, L. Prep. 1. (Extractum sennæ aquosum, L.)—a. As EXTRACT OF COLOCYNTH—Ph. L.

b. (P. Cod.) As EXTRACT OF BISTORT—P. Cod.

c. (Ph. Bor.) From senna leaves, by maceration in tepid water (104° Fahr.) for 24 hours, and expression and filtration; the operation is repeated with fresh water, and the strained liquors evaporated to a thick extract (at 149° to 157° Fahr.), which is dissolved in water, 4 parts, the solution filtered, and again evaporated.—Dose, 10 to 20 gr. It is principally used as a basis for purgative pill. When prepared by decoction it is nearly inert. A better extract is prepared from the common tincture made with proof spirit.

2. Alcoholic; Extractum sennæ alcoholicum, L.—(Guibourt.) Senna (in powder), 1 part; rectified spirit, 5 parts; heat gradually to boiling, let it cool; in 24 hours express, strain, and repeat the process with fresh spirit; lastly, distil and evaporate. Proof spirit answers for this purpose.

3. (Fluid; Extractum sennæ fluidum, L.—Ph. (U. S.) Senna (in coarse powder), 2⁄2 lbs.; spirit (at or near proof), 64 fl. oz.; macerate 24 hours, then act by displacement, subsequently adding weak spirit (1 of rectified spirit to 3 of water) until 10 pints of tincture are obtained; evaporate to 1 pint, filter, add sugar, 20 oz., and oil of fennel, 1 fl. dr. (dissolved in) compound spirit of ether, 2 fl. dr. Every fl. oz. represents 1 oz. of senna.

Extract of Smoke. Syn. Extractum fuliginis, L. Prep. 1. (Aqueous.) Wood-soot, 2 oz.; water, 1 pint; boil to 16 fl. oz., filter, and evaporate.

2. (Acetic.) Wood-soot, 2 oz.; distilled vinegar and water, of each, ⁄2 pint; as the last. Formerly reputed antispasmodic, alterative, &c.—Dose, 3 to 6 gr., 2 three times a day; in dyspepsia, hysteria, cancer, scrofula, and various syphilitical affections.

Extract of Snake-root. See Extract of Senega.

Extract of Black Snake-root (fluid). Syn. Extractum cimicifugæ fluidum (Ph. U. S.). Prep. As FLUID EXTRACT OF CUBEBS. (Ph. U. S.)

Extract of Soap′wort. Syn. Extractum saponariæ, L. Prep. (P. Cod. & Ph. Bad.) From the dried roots of soapwort (Saponaria officinalis), as EXTRACT OF BISTORT—P. Cod. Aperient and alterative.—Dose, 15 gr. to ⁄2 dr.

Extract of Spruce. See Essence of Spruce.

Extract of Squills. Syn. Extractum scillæ, L. Prep. 1. (Aqueous; E. s. aquosum.—a. (Ph. Baden.) From squills, as EXTRACT OF COLOCYNTH—Ph. L. (nearly).

b. (Ph. Bor.) From squills, as EXTRACT OF SENNA—Ph. Bor. (nearly), but using boiling water, avoiding ebullition during the evaporation, and powdering the residuum.—Dose, 1 to 5 gr.

2. (Alcoholic; Extractum scillæ alcoholicum, L.—P. Cod.) From the tincture prepared with proof spirit, by distillation and evaporation.—Dose, ⁄2 to 3 gr., as an expectorant and diuretic, twice or thrice a day. In larger doses it is nauseant and emetic.

3. (Acetic; Extractum scillæ aceticum.) Digest powder of squills, 1 lb., in acetic acid, 3 oz.; and distilled water, 1 pint, with a gentle heat, for 48 hours.

Express strongly, and without straining; evaporate to a proper consistence. (One grain of this is said to equal three of the powder.)

Extract (fluid) of Stillingiæ. Syn. Extractum stillingæ fluidum (Ph. U. S.). Prep. Stillingia, in fine powder, 16 oz. (troy); macerate with 12 oz. (old measure) of rectified spirit; 3 oz. (old measure) of glycerin; and 1 oz. (old measure) of water, for four days in a closed percolator, and proceed as for FLUID EXTRACT OF COTTON-ROOT. (Ph. U. S.)

Extract of Stor′ax. See Styrax.

Extract of Stramo′′nium. Syn. Extract of thorn-apple; Extractum Stramonii, (Ph. L. & D.), L. Prep. 1. (B. P.) Pack stramonium seeds, coarsely powdered, in a percolator, and pass about their own weight of washed ether slowly through them, remove the ether, and set aside. Now pour over them proof spirit until the seeds are exhausted; distil off the spirit, and evaporate the residue by a water bath to a proper pill consistence.—Dose, ⁄4 gr., gradually increasing.

2. (Ph. L.) Seeds of thorn-apple (Datura stramonium), 15 oz.; boiling distilled water, 1 gall.; macerate for 4 hours in a vessel lightly covered, near the fire; afterwards take out the seeds, bruise them in a stone mortar, and return them to the liquor; then boil down to 4 pints, strain whilst hot, and evaporate. The Ph. D. is similar. Product. (About) 12%, Anodyne and narcotic.—Dose, ⁄4 gr. to ⁄2 gr., gradually increased, twice or thrice a day; neuralgia, rheumatism, tic doloureux, spasmodic asthma, epilepsy, worms, &c.

3. (P. Cod. & Ph. U. S.) From the expressed juice of the fresh leaves, heated to boiling, and filtered. The P. Cod. also orders it to be prepared as EXTRACT OF ACONITE—Ph. L. Anodyne and narcotic.—Dose, ⁄2 gr. to 1 gr.

Obs. On the large scale, this extract is prepared by expressing the juice of the fresh herb, and boiling the remainder in water; the juice and decoction are then mixed, filtered, and evaporated. 1⁄2 cwt. of stramonium yielded 37 lbs. of juice, and this, with the decoction, gave 31 lbs. of extract. (Gray.)

4. (Alcoholic; Extractum stramonii—Ph. E., E. s. alcoholicum, L.)—a. (Ph. E. & Ph. U. S.) From the seeds (ground in a coffee-mill), by percolation with proof spirit. Product. (About) 14%; 1 lb. yielded 2⁄4 oz. (Recluz.)

b. (P. Cod.) From the leaves, as EXTRACT OF ACONITE—P. Cod.—Dose, ⁄4 gr. gradually increased. (See above.)

Extract of Suc′cory. Syn. Extractum chicorii, L. Prep. (Guibourt.) From the fresh root, as EXTRACT OF ACONITE—Ph. L. Aperient, deobstruent, and tonic.—Dose, 10 gr. to ⁄2 dr.

Extract of Sweet Flag. Syn. Extractum acidi, E. calami aromatici, L. Prep. From the rhizomes, as EXTRACT OF RHUBARB—Ph. L. See Sweet Flag.

Extract of Tan′sy. Syn. Extractum tanaceti, L. Prep. 1. From the herb (Tanacetum vulgaris), as EXTRACT OF HOP—Ph. L.

2. (Giordano.) As EXTRACT OF HOREHOUND—Ph. Lusitan.

Obs. This extract is said to be tonic, stomachic, anthelmintic, emmenagogue, and febrifuge. Dr Clark says that in Scotland it was found to be serviceable in various cases of gout. The infusion is, however, preferable.—Dose, 5 gr. to 20 gr.

Extract of Taraxacum. Syn. Extract of dandelion; Extractum taraxaci (Ph. L. & E.), E. t. herbæ et radicis (Ph. D. 1826), L. Prep. 1. (B. P.) Crush fresh dandelion root, press out the juice, and allow it to deposit; heat the clear liquor to 212° F., and maintain the temperature for 10 minutes; then strain and evaporate by a water bath, at a temperature not exceeding 160° F. to a proper consistence.—Dose, 5 to 15 grains.

2. (Ph. L.) From the recent root of dandelion (Leontodon Taraxacum), as EXTRACT OF HOP—Ph. L. The formulæ of the Ph. E. & U. S. are nearly similar.

3. (Ph. D.) From the herb and root, as the other simple extracts (EXTRACTA SIMPLICIORA).

4. (P. Cod.) From the expressed juice, as EXTRACT OF STRAMONIUM—P. Cod.)

5. (Ph. Bor.) As EXTRACT OF SENNA—Ph. Bor. (nearly).

6. (Ph. Baden.) By displacement with cold water.

7. (Wholesale.) From the decoction.

8. (Fluid.) See Liquor of Taraxacum.

Obs. The extract of the shops is usually prepared by exhausting the root by coction with water. The products of the first two of the above formulæ, when recent, have a faint and agreeable odour, and a sweet bitter taste; those of Nos. 4, 5, and 6, smell strongly of the recent root, have a pale and lively brownish-yellow colour, and a bitter acidulous taste, without any trace of sweetness; that of the last one is devoid of odour, and possesses a coffee-brown colour, and a sweetish, burnt taste, not much unlike a solution of burnt sugar. The medicinal virtue of this extract is greatest when the aroma and bitter taste of the recent root is well developed; and when sweet, its efficacy as a remedy is impaired. (Squire.)

Taraxacum root should be gathered during the winter months, when the quantity of the product is looked at; as then a given weight of the juice yields more extract; but in summer and autumn it possesses more bitterness and aroma. 4 lbs. of juice from roots gathered in November and December yielded 1 lb. of extract, while it took from 6 to 9 lbs. of juice from the root, gathered in spring or summer, to yield a like quantity. (Squire.) The herb yields by the evaporation of its expressed juice about 5% of extract. According to Mr Jacob Bell, the average yield of 1 cwt. of root is about 7⁄8 lbs. (‘Pharm Journ.,’ x, 446.)

Good extract of taraxacum should be wholly soluble in water.—Dose, 10 gr. to ⁄2 dr.; as a resolvent, aperient, and tonic, in liver and stomach complaints, &c.

Extract of Tea. Syn. Extractum theæ, L. Prep. 1. From an infusion of any of the rougher kinds of black tea. Astringent. Has been recommended in diarrhœa; formed into pills.—Dose, 10 gr. to ⁄2 dr. A hard, black-looking substance, smelling and tasting faintly of tea, is imported under the same name from China.

2. (Pidding’s.) The joint products of distillation and infusion combined. Proposed to be made in China, and exported as a condensed preparation of tea. (Essence of tea; Essentia theæ); to be used as a substitute for the leaves, in order to save the expense of freight, &c.

Extract of Thorn-Apple. See Extract of Stramonium.

Extract of Tobac′co. Syn. Extractum tabaci, E. Nicotianæ, L. Prep. 1. (Chippendale.) From decoction of tobacco. Proposed as an external application in neuralgia, &c.

2. (Alcoholic; Extractum tabaci alcoholicum, L.—Ph. Bor.) Tobacco leaves, 1 lb.; spirit (sp. gr. ·900), 2 lbs.; digest in a warm place for some days, express strongly, and again digest in a mixture of water and spirit (·900), of each, 1 lb., for 24 hours; again press out the liquor, and evaporate the strained and mixed liquors into a vapour bath, at a temperature not exceeding 167° Fahr.

Extract of Tor′mentil. Syn. Extractum tormentillæ, L. Prep. (Ph. Amst.) From the root of Potentilla Tormentilla, as EXTRACT OF HOPS—Ph. L. The Ph. Baden directs its preparation by displacement with cold water. Astringent and febrifuge.—Dose, 15 to 30 gr.; in diarrhœa. It was formerly regarded as a specific in syphilis. (Lindley.)

Extract of U′va Ur′si. See Extract of Whortleberry.

Extract of Valer′ian. Syn. Extractum valerianæ, L. Prep. 1. From valerian root, as EXTRACT OF HOP—Ph. L.; but using a covered vessel.

2. (Ph. Bor. and Baden.) As EXTRACT OF CINCHONA—Ph. L. (nearly), employing strong force in the expression of the liquor, and only evaporating to the consistence of syrup.

Obs. It is usual to add to this extract a little of the ESSENTIAL OIL OF VALERIAN, dissolved in a small quantity of rectified spirit, just before removing it from the evaporating-pan, and when nearly cold. Anti-spasmodic and nervine.—Dose, 10 gr. to ⁄2 dr. In hysteric and spasmodic diseases. Valerian yields about 40% of soft extract.

3. (Alcoholic; Extractum valerianæ alcoholicum, L.—P. Cod.) As EXTRACT OF BOX.—P. Cod.

4. (Fluid; Extractum valerianæ fluidum, L.—Ph. U. S.). Rectified spirit, 12 fl. oz.; mix, add of valerian (in coarse powder), 8 oz. digest and percolate, adding, subsequently, spirit (at or near proof) until 16 fl. oz. of tincture have passed through; let this evaporate spontaneously, in a shallow vessel, until reduced to 5 fl. oz.; in the meantime add fresh spirit to the mass in the percolator, until 10 fl. oz. more of tincture are obtained, which add to the above residuum of the evaporation, observing to dissolve any oleo-resinous deposit in a little rectified spirit, and add to it to the rest; lastly, filter, and add of rectified spirit, q. s. to make the whole measure 16 fl. oz.

Extract of Vanil′la. See Liquor of Vanilla.

Extract of Wall Pel′litory. Syn. Extractum parietariæ, L. Prep. From fresh wall-pellitory (Parietaria officinalis), as EXTRACT OF ACONITE—Ph. L. Aperient, diuretic, and pectoral.—Dose, 10 gr. to ⁄2 dr.

Extract of Wal′nut. Syn. Extractum juglandis immaturæ, L. Prep. 1. From unripe walnuts (Juglans regia), as EXTRACT OF ACONITE—Ph. L.

2. From the decoction of the green shells. Vermifuge.—Dose, 20 to 30 gr. in cinnamon water.

Extract of Walnut Leaves. Syn. Extractum juglandis foliorum, L. Prep. 1. From the decoction of dried walnut leaves.

2. (Soubeiran.) By displacement with tepid water. Diaphoretic and alterative.—Dose, 2 to 4 gr., twice or thrice a day; in scrofula, scirrhus, &c.

3. (Alcoholic; Extractum juglandis foliorum alcoholicum, L.—Ph. Bor.) From walnut leaves (cut), as ALCOHOLIC EXTRACT OF TOBACCO—Ph. Bor. (nearly).

Extract of Wa′ter-dock. Syn. Extractum rumicis aquatici, L. Prep. From the root, as EXTRACT OF HOPS, Ph. L. Astringent and antiscorbutic.—Dose, 15 gr. to 1 dr.; in skin diseases, &c.

Extract of Whor′tleberry. Syn. Extract of bearberry; Extractum uvæ ursi. (Ph. L.), L. Prep. 1. From the dried leaves of the bearberry (Arctostaphylos Uva-Ursi), as EXTRACT OF HOPS—Ph. L.—Dose, 5 to 15 gr., twice or thrice a day; in chronic diseases of the bladder and kidneys, attended with increased secretion of mucus, without inflammation.

2. (Ph. U. S. Extractum uvi-ursi eluidum.) As fluid extract of cotton-root. (Ph. U. S.)

Extract of Willow Bark. Syn. Extractum salicis. (Ph. Par.) From Powdered willow bark, as EXTRACT OF RHATANY.

Extract of Win′ter Cher′ry. Syn. Extractum alkekengi, L. Prep. From the berries of Physalis alkekengi, as EXTRACT OF ELDER. Aperient, detergent, and diuretic. Dose, 2 to 4 dr.

Extract of Win′ter-green. Syn. Extract of pipsissewa; Extractum chimaphilæ, L. Prep. From the herb winter-green or pipsissewa (Chimaphila umbellata), as EXTRACT OF HOPS—Ph. L.—Dose, 10 gr. to ⁄2 dr.; in dropsy, scrofula, and chronic affections of the urinary organs.

Extract of Wood Sor′rel. Syn. Extractum acetosellæ, L. Prep. (Pideret.) From the expressed juice of the fresh herb (Oxalis acetosella.) Acid, bitter, and antiscorbutic.—Dose, 15 gr. to ⁄2 dr.

Extract of Worm Grass. See Extract of Pinkroot.

Extract of Worm′seed. Syn. Extractum cinæ æthereum, E. seminum c. æ., L. Prep. (Hamb. Cod. 1845.) Wormseed, 1 oz.; ether, 4 oz.; digest 3 or 4 days, press, filter, distil off 4-5ths, and evaporate the residuum to a proper consistence. Prod. 25% to 30%. Vermifuge.—Dose, 3 to 10 gr., night and morning, for 2 or 3 successive days, followed by a brisk purge.

Extract of Worm-wood. Syn. Extractum absinthii; Extractum artemesiæ absinthii, L. Prep. 1. (Ph. D., 1826.) From the dried flowering tops of wormwood, as the other simple extracts (EXTRACTA SIMPLICIORA—Ph. D.)

2. (Ph. Bor.) As EXTRACT OF RHATANY—Ph. Bor.

3. (P. Cod. and Ph. Baden.) By displacement by cold water.

Obs. Bitter, stomachic, tonic, and vermifuge.—Dose, 10 gr. to 20 gr., 2 or 3 times daily; in dyspepsia, loss of appetite, gout, &c. It is usual to add a few drops of the oil of wormwood to the extract before taking it from the pan.

4. (Alcoholic; Extractum absinthii alcoholicum, L.— Guibourt.) From a tincture prepared from the dried tops of wormwood boiled in proof spirit. More active than the last.

Extract of Yew. Syn. Extractum taxi, L. Prep. 1. (Loder.) From the inspissated juice of the fresh leaves of the yew (Taxus baccata). Its action on the circulation greatly resembles that of digitalis, but is more manageable.—Dose, 1 to 7 gr.; in epilepsy, &c.

2. (Alcoholic,—Ph. Baden.) From the dried leaves, as ALCOHOLIC EXTRACT OF ACONITE—Ph. Baden.

Obs. In addition to the preparations given above, there are many others which are often called ‘EXTRACTS,’ These may be grouped under the following heads:—

Extracts, Concentra′ted. Syn. Resinoids. Pharmaceutical preparations of more or less value, largely employed by the American physicians who style themselves ‘ECLECTICS,’ They are supposed to present in the most concentrated form the medicinal virtues of the plants from which they are derived. See Resinoids.

Extracts, Fluid. Syn. Extracta fluida, Extracta liquida, L. This name has been applied in modern pharmacy to various preparations differing materially from each other in their degree of fluidity and concentration. Some of these have been already noticed, and others will be found under one or other of their synonyms. Much confusion would be avoided by confining the name ‘FLUID EXTRACT’ to those preparations only which differ from the ordinary officinal extracts in being in the liquid form; whilst others of a like character, but of less consistence or concentration, might be conveniently classed under the general denomination of ‘LIQUORS’ (LIQUORES, L.). The various condensed preparations of vegetable substances, now common in trade, professedly several times stronger than the common DECOCTIONS, INFUSIONS, and TINCTURES, might be simply and advantageously distinguished by the addition of ‘CONCENTRATED’ to their names. Tinctures made with rectified spirit, and of (say) at least 8 times the usual strength, might be appropriately termed ‘ESSENCES,’ See Decoction, Essence, Extract, Infusion, Oleo-resin, Syrup, Tincture, &c.

Extracts, Perfu′matory. See Extrait.

Extracts, Pulver′ulent. Syn. Dried extracts, Desiccated e.; Saccharated e.; Extracta pulverata, E. sicca, E. cum saccharo, L. Prep. 1. Ordinary soft extract of the drug, 4 parts; white sugar (in powder), 1 part; mix, and dry by exposure in a warm situation; lastly, reduce the mass to powder, and if it weighs less than 4 parts, triturate it with more powdered sugar until its weight is equal to the original weight of the extract used in its preparation. The strength of the extract thus continues unchanged.

2. (Ph. Bor.) As the last, but using powdered sugar of milk, in lieu of cane sugar.

3. (Gauger.) Alcoholic extract, 3 parts, rectified spirit, 1 part, are triturated together in a porcelain mortar until thoroughly incorporated, when white sugar (in powder), 15 oz., is gradually added, and the two carefully and completely blended together; the mixture is dried as before, and more sugar added until the whole weighs exactly 18 oz. Six grains represent one grain of the unprepared extract.

Obs. The above are admirable preparations, intended chiefly to render the perishable extracts of the narcotic plants (EXTRACTA NARCOTICA) less liable to suffer by age. See Extract of Aconite (Saccharated), &c.

EXTRAC′TIVE. Syn. Extractive principle. Fourcroy entertained the belief that all vegetable extracts contained a common basis of definite composition, to which he gave the name of extractive. Chevreul and other chemists have shown, however, that Fourcroy’s extractive is not a chemical compound but a heterogeneous mixture, varying in composition with the plant from which it is obtained. Extractive has a brown colour, or one becoming so in the air; it speedily putrefies, and becomes oxidised, and is rendered insoluble by long exposure to air, and by repeated solutions and evaporations. In its unaltered state it is soluble in water and in alcohol, is nearly insoluble in ether, and is precipitated from its solutions by the acids and metallic oxides. With alumina it forms the basis of several brown dyes.

EXTRAIT. [Fr.] Literally an extract. Among perfumers, extraits are mostly spirituous solutions of the essential oils or odorous principles of plants and other fragrant substance. The French commonly apply the term to any concentrated spirit, either simple or compound. In the shops of the Parisian perfumers upwards of 60 preparations of the kind are distinguished by this name. The extracts of JASMINE, JONQUIL, MAY-LILY, ORANGE BLOSSOMS, VIOLETS, and other like flowers of delicate perfume, are obtained by agitating and digesting the ‘huiles’ and ‘pomades’ of the flowers with the purest rectified spirit in the manner described under Scented Spirits (‘esprits’). This process is repeated with fresh oil or pomade until the spirit is rendered sufficiently fragrant. The other extracts (both simple and compound) are made by the common methods of infusion and distillation. See Essence, Extract, Spirit, &c.

EYE. In anatomy and physiology, the organ of vision. In order that vision may be distinct, it is necessary that the pencil of rays diverging from each point of the object and entering the pupil should converge to a focus on the retina. Near-sightedness (‘MYOPIA,’ L.) is due to the too great convexity of either the ‘lens’ or ‘cornea,’ causing the rays to converge to a focus before reaching the retina. The spectacles worn by myopic persons have concave glasses, which, by increasing the divergence of the rays falling upon the eye, have the effect of carrying back each focal point towards the retina. In the long sight of old people (‘PRESBYOPIA,’ L.) the foci of the refracted pencils are situated behind the retina, the ‘lens’ or the ‘cornea’ being not sufficiently convex. This defect is corrected by convex glasses, which increase the convergence of the incident rays.

Foreign Bodies in the Eye.—Particles of dust, small insects, hairs, and such like minute bodies frequently get under the eyelid, and thus become a source of considerable discomfort, and very frequently of great pain. Hence the necessity of their prompt removal. In order to effect this the inside of the lids should be so exposed as to reveal the intruding substance. The lower lid may be easily turned down so as to show the inner surface, but the upper lid cannot be so easily manipulated. The end, however, may be attained by taking firm hold of the lid with the finger and thumb, drawing it downward and forward, placing a quill or a small pencil-case on the outer upper part, and turning the lid backwards over it. When the annoying particle is seen it should be removed by gently drawing over it, with a wiping motion, a piece of rag or linen handkerchief, wrapped round the finger, or by means of a camel-hair brush, if this latter be at hand.

If these means fail to remove it, and it should be imbedded too firmly in the membrane, it may be picked off with a tooth-pick, the end of a pair of tweezers, a fine ivory paper-knife, or with a stiff hair from a clothes-brush bent at right angles. If lime-dust has blown into the eye it is only the larger particles that can be removed in this manner; the finer particles may be dissolved out by washing the eye with a lotion made of one part of common vinegar and two parts of water. A drop or two of pure sugar syrup will also frequently dissolve the lime. When a powerfully destructive substance, such, for instance, as sulphuric acid or oil of vitriol, is, as sometimes happens, thrown by some person into the eye, the best course is to wash it out with a solution containing four grains of washing soda in an ounce of water. This should be done as quickly as possible, and pending the time the soda lotion is being got ready, the eye, being kept open, should be diligently washed with cold water. Grains of gunpowder should be carefully removed. Hot fluid, such as melted fat or pitch, may be got rid of by putting into the eye a few drops of almond or olive oil.

Upon removal of the foreign body the pain generally subsides; but it sometimes happens that the membranes may be lacerated, in which case more or less inflammation may ensue. Under these circumstances a medical practitioner should be consulted. For animals the same treatment may be followed. See Blindness, Colour Blindness, Vision, &c.

Eye Balsam, Vegetable (Martin Reichel, Würzburg). Opium, 5 parts; oxide of mercury, 5 parts; camphor, 2 parts; wax cerate, 52 parts. (Hager.)

Eye Drops. See Water (Eye).

Eye Essence (Dr Romershausen). A tincture prepared from fennel seeds and fresh young fennel. (Hager.)

Eye Powder (Laeyson, Paris), also known as Odorous Powder. For the strengthening, restoration, and preservation of the sight. A powder composed of—Burnt chalk, 100 parts; ammonia, 50 parts; charcoal, 6 parts; oxide of iron, 2 parts; cinnamon bark, 2 parts. (P. L. Geiger.)

Eye Pow′ders. See Collyria.

Eye Salt. Powdered alum. (G. Graefe.)

Eye Salve. See Ointment (Eye).

Eye Snuff. See Snuff.

Eye Water (Biedermann, Annaberg). 2 grms. sulphate of zinc in 60 grms. distilled water, with a little infusion of cloves.

Eye Water (Brun) is a solution of 4 parts of aloes in 32 parts of white wine, with 32 parts of rose water, and 1⁄2 part of tincture of saffron.

Eye Water (Chantomelanus) “makes spectacles superfluous.” A turbid yellow-brownish liquid, consisting of a weak extract of lavender flowers in diluted spirit, in which some oil of lavender has also been dissolved. (Opwyrda.)

Eye Water, Dr Graefe’s (L. Roth, Berlin). Sulphate of zinc, 1·5 grms.; fennel water, 100 grms., slightly coloured with fennel seed tincture. (Schädler.)

Eye Water (J. P. H. Hette). A solution of ethereal oils of lavender, bergamot, rosemary, and tincture of opium in spirits of wine, 50 per cent. (Wittstein.)

Eye Water (Bernhard Kraft, Calbe) for acute inflammation of the eyes and for strengthening the sight. Seven grammes of an impure muddy sediment-leaving spring water containing half a gramme of native sulphate of zinc containing iron. (Schädler.)

Eye Water (Inspector Stroinski, Neisse). One part of sulphate of zinc dissolved in 500 parts of common river water. (Schreiber.)

Once a trace of patchouli perfume was added to this water. (Hager.)

Eye Water, Dr White’s (T. Ehrhard, Altenfeld, Thuringia). Four cloves, a piece of cinnamon the size of a large pea, 2 teaspoonfuls of rose water, 1 drop of vinegar, 10 drops of arnica tincture. Digest for an hour and filter. Dissolve in the filtrate some white vitriol of the size of a pea. (Hager.)

Sulphate of zinc, 3 parts; honey, 4 parts; water, 80 parts; perfumed with oil of cloves and a trace of mustard oil. (Wittstein.)

Eye Waters. See Water.

FACE A′GUE. The common name for the intermittent form of facial NEURALGIA or TIC DOULOUREUX. See Neuralgia.

FACE PAINTS. Syn. Fards, Fr. See Bloom, Carmine, Pearl White, Rouge, &c.

FAC-SIM′ILE. An exact imitation of an original in all its traits and peculiarities. The term is chiefly used in relation to copies of old manuscripts, or of the handwriting of famous men, or of interesting documents, produced by engraving or lithography. See Signatures.

FACTI′′TIOUS. Syn. Factitius, L. Artificial; made by art, in distinction from that produced by nature. Numerous illustrations of the application of this word occur in the pages of the present work.

FÆCES. Excrement. In the laboratory, the ‘settling’ or sediment deposited by a liquor. See Defecation, Excreta.

FAINT′ING. Syn. Swooning; Syncope, Deliquium animi, L. In pathology, a state in which the respiration and circulation are apparently suspended for a time, or are extremely feeble. The symptoms are too well known to require description. The causes are supposed to be—diminished energy of the brain, and organic affections of the heart or neighbouring vessels. This has led nosologists to divide syncope into two varieties:—

1. Occasional (syncope occasionalis, s. accidentalis, L.), primitively induced by sudden and violent emotions of the mind, powerful odours, derangement of the stomach or bowels, constrained position of the body, tight-lacing, pressure, loss of blood, debility from disease, &c. This variety is frequently followed by vomiting, and, occasionally, by convulsions or epileptic fits. The recovery is accelerated by the horizontal position, without the head being the least elevated, by which the arterial blood is more vigorously thrown upon the brain, and thereby stimulates it to resume its usual functions. Pungent substances (smelling-bottle, vinaigrette, &c.) may be applied to the nostrils, and cold water sprinkled on the face and chest. In all cases the dress (corset, waist-band, neck-cloth, &c.) should be instantly loosened, and indeed this is the first assistance which should be given, either in syncope or apoplexy. As soon as the patient can swallow, a little brandy-and-water, or wine, or a few drops of ether or spirit of sal volatile, may be given.

2. Cardiac (syncope cardiaca, L.), arising without any apparent cause, with violent palpitation during the intervals, and altogether of a more formidable character than the preceding. The subsequent treatment must here be directed to the cure or alleviation of the original disease.

FAINTS. The first and last runnings of the whiskey-still. The one is technically termed the ‘strong faints,’ the other, the ‘weak faints.’ They are both purified by rectification, &c. See Distillation.

FAITH. Dr Pereira remarks, that “faith in the beneficial agency of remedies, and confidence in the skill of the medical attendant, are important adjuvants in the treatment of disease. To them both the physician and empiric owe part of their success.”

FAL′LING SICK′NESS. See Epilepsy.

FAMILIENSALBE, Family Ointment (Göring). 16 grammes of a hard yellow salve in a round box; a mixture of 9 parts wax, 3 parts fat; 2 parts turpentine, 2 parts inspissated juice of Ornithogalium scilloides Jacquin, or O. candatum Aiton. These plants are known to the public as Meerzwiebel (sea onion or squill), but they are only related to that plant in appearance. (Hager.)

FAR′CY. See Glanders.

FARDEL-BOUND. Syn. Clue-bound, Wood-evil. An affection of the third stomach of cattle, induced by their unduly partaking of coarse indigestible food. Cattle are most commonly attacked by fardel in summer and autumn, when they are able to get at tough, strong, and hard grass. It is also frequently caused by rye-grass in seed and ripe vetches, as well as by eating largely of the shoots of trees or the cuttings of hedges, a circumstance which has given rise to the disease being called ‘wood-evil.’ Sometimes an attack may be brought on through over-feeding, combined with a deficiency of water. The symptoms vary greatly in intensity, and are often some days before they definitely manifest themselves. The animal ceases to ruminate, refuses food, and, if a cow, the secretion of milk is stopped. Then, after a day or two fever (indicated by heat and dryness in the nose and mouth) comes on, with somewhat quickened circulation and breathing, the breathing by the second or third day being accompanied by a grunt at the beginning and end of respiration, which is very noticeable when an attempt is made to move the animal.

In all attacks the animal suffers from obstinate constipation. The first stomach is frequently much distended, and if any fæces are passed they are caked, dark coloured, and of variable consistence.

When the disease is attended with most of these symptoms, the animal may live ten days or a fortnight; but unless relief is afforded, nausea very frequently sets in, and continues to increase, the pulse at the same time getting gradually weaker, and the strength failing. In some instances the animal has an epileptic fit, and in others death is preceded by great stupor; whilst in others, again, if it be a horse, it is attacked with stomach staggers.

“The treatment consists in removing the obstinate constipation by powerful purgatives, advantage being taken to gain their utmost efficacy by combining several together, and giving them along with plenty of fluid.

“Three-quarters of a pound each of Epsom and of common salt, twenty croton beans, and a drachm of calomel, will suffice for a full-grown, middle-sized ox or cow, and must be administered in three or four bottles of water or very thin gruel. In this disease there is little fear of giving too much medicine.

“The action of the purgatives is greatly expedited by the use of occasional stimulants, which in diseases of the digestive organs of cattle may be given without fear of engendering or aggravating inflammation. Every encouragement must be used to get the animal to drink, for large quantities of fluid are obviously most essential in washing out the obstruction which causes the evil. The cessation of the grunt, the passage of some hard cakes of dung, with the subsequent abatement of the fever, are the signs of amendment for which we watch; but even after the first movement of the bowels considerable attention, a sloppy diet, and several doses of purgative medicine, are requisite to empty the canal and prevent the recurrence of the obstruction. If twenty hours elapse after the administration of the above combination without any action of the bowels, the same dose may be repeated, along with a good quantity of some stimulant, such as a bottle of ale, with two ounces of oil of turpentine and two ounces of ginger. Half the quantity of the purgative may be given at the end of a like interval, if no effect be produced; but the further employment of purgatives is injurious, inasmuch as it increases the nausea without expediting the action of the bowels.

“A week will sometimes elapse without any alvine evacuation; in some cases I have known ten or eleven days, and in some fifteen days. Yet even in these recovery took place; and so long as stupor and frenzy are staved off, there is always hope of a cure. After the prompt and energetic adoption of the treatment recommended, little further remains to be done except to withhold all solid indigestible food, administer frequent quantities of water, or any simple fluid, which must be horned over if the beast will not take it; allow also plenty of treacle, and encourage the action of the medicine by clysters, scalding the belly, and occasional exercise. Blood-letting is not only useless, but even injurious.” (Finlay Dun.)

FAR′INA. The flour of any species of corn, pulse, tuber, or starchy root. The most important kinds of farina are noticed under their respective heads. The following dietetic articles of a farinaceous character are extensively advertised:—

Baker’s Alimentary Compound. Fine flour (pastrycook’s), 2 parts; finely ground rice, 1 part.

Baster’s Compound Farina. Wheat flour, 14 oz.; white sugar, 2 oz.

Braden’s Farinaceous Food. Similar to Hard’s (below).

Bright’s Nutritious Farina. Rice flour and potato starch, equal parts.

Bright’s Breakfast Powder. Chocolate, 1 part; nutritious farina (Bright’s) 2 parts.

Bullock’s Semola. Wheat flour, from which a portion of the starch has been removed, so as to leave an excess of gluten.

Denham’s Farinaceous Food. Wheat flour, 3 parts; barley meal, 1 part; the mixture is slightly baked, and again ground and sifted. Said to be slightly laxative.

Duryea’s Maizena. Indian corn starch prepared for food.

Gardiner’s Alimentary Preparation. Pure rice flour, very finely ground.

Hard’s Farinaceous Food. Wheat flour, slightly baked, and resifted.

Kingsford’s Oswego Prepared Corn. An excellent preparation of Indian corn.

Leath’s Alimentary Farina. Wheat flour (baked), with some sugar, Indian corn meal, and tapioca. According to some, it also contains potato starch.

Maidman’s Nutritious Farina. Potato starch tinged with beet-root or other pink colouring matter.

Plumbe’s Farinaceous Food. South-sea arrow-root, with about 1-3rd its weight of pea flour.

Polson’s Corn Flour. The starch of Indian corn or maize prepared with great care. It is much used as a substitute for arrow-root, and for custards, puddings, &c.

Smith’s Nursing Farina. Equal parts of baked wheat flour and rice flour.

Obs. Many of the above compounds are deficient in the nitrogenous elements of nutrition, and all of them nearly destitute of the mineral and saline matters which are absolutely necessary to the formation of the bones and tissues, and the support of the body in health, and are consequently utterly unsuitable as an exclusive article of diet, especially for young children. Unfortunately, it has been too much the fashion of medical men of late years to recommend these compounds, and even to furnish testimonials as to their excellence, apparently relying solely on the representation of their proprietors or vendors. We deem it, however, to be a public duty to caution parents and nurses against their injudicious use. As mere adjuvants or auxiliaries, when the natural food supplied by the mother may be insufficient for the nutrition of the infant, some of them may doubtless be of value; but in all other cases they should be largely combined with pure cow’s milk, beef tea, meat broths or gravies, eggs, or other substances rich in the nitrogenous and saline elements of nutrition.

FARM′ING. The business or management of a FARM. Formerly farming was looked upon as a profession easily understood, and successfully pursued only by an empiric. It is now, however, regarded in a different light, and the farmer, to succeed, not only requires perseverance and observation, but also a sound knowledge of natural sciences. See Butter, Cheese, Implements, Manures, Soils, &c.

FARMS, SEWAGE. See Sewage Farms.

FAT. Syn. Adeps, L. The fat of animals is a concrete oil contained in the cellular membrane of their bodies, more especially round the kidneys, in the folds of the omentum, at the base of the heart, upon the surface of the intestines, and among many of the muscles. Fat varies in consistence, colour, and odour, with the animal from which it is obtained. That of the carnivora is usually soft and rank-flavoured; that of the ruminantia solid and nearly scentless. It is generally whitest and most copious in the well-fed young animal, and yellowish and more scanty in the old. That under the skin and surrounding the kidneys (suet) is also more solid than that in the neighbourhood of the movable viscera. In the cetacea, or whale tribe, the fatty secretion assumes the form of oil. These variations in consistency depend upon the relative proportions of solid stearin and liquid olein present in the fat.

The vegetable fats are found in various parts of certain plants, but are generally most abundant in the seeds. They are extracted by simple pressure or else by boiling. Two kinds of vegetable fat, namely, palm-oil and cocoa-nut oil, are extensively employed in the useful arts.

All fats are lighter than water. They are all soluble in ether, benzol, and turpentine, and may be mixed with each other in any proportion.

In former times the fats of many animals were employed in pharmacy, but at present those principally used are lard and suet. In perfumery, in addition to these, beef marrow and bear’s grease are employed. For both these purposes the crude material is cut into small pieces, and freed as much as possible from all extraneous membranes; after which it is placed in a boiler with water, and heated until it is completely fused, when the whole is strained, and allowed to cool very slowly. By this means a cake of cleansed fat is obtained, which may be readily separated from any adhering water.

Fats and the fat oils are best preserved by being run into glazed jars, and secluded from the action of the air. A little benzoic acid or gum-benzoin, dissolved in them by heat, will generally prevent, and in all cases greatly defer, the accession of rancidity. We introduced this method into the laboratory in our early days of manipulation, and ourselves, and others to whom we have made it known, have since employed it with undeviating advantage in the manufacture of cerates, ointments, and other preparations containing fatty matter or the fixed oils. It has been shown by Dr Griesler that nitric ether, and its alcoholic solution, act in the same manner. A few drops are not only sufficient to prevent rancidity, but, it is said, will even destroy the disagreeable odour of rancid fat. When heated to remove the alcohol, they immediately become bright, clear, and scentless. See Oil, Glycerin, Olein, Palmitin, Stearin, Tallow, &c., also below.

Fat, to melt down. Let all the small pieces of fat cut off joints, &c., be collected, divided into small pieces, put in a stew pan (a little water being added to prevent their burning), and placed on the fire. This must be stirred carefully at intervals to prevent any of the pieces of fat sticking to the bottom.

When thoroughly melted (which it will be in about an hour and a half) pour through a strainer into a basin with some cold water in it. Thus prepared, dripping or fat may be used instead of suet, and there are few who would know any difference between them. Dripping, if clarified as above, may be used over and over again for frying, provided it has not been previously employed in dressing fish, in which case it will impart a fishy taste. But it can be used repeatedly for fish if it is kept for that purpose only. The skimmings off the top of the saucepans, while a piece of meat is boiling, will also do capitally for light puddings.

FAT′TY ACIDS. In chemistry, compounds having acid properties derived from the various fats and oils. The radicals of these acids exist in the natural fats combined with a base called glyceryl. When fats are saponified by an alkali, stearate, palmitate, and oleate of potassa or soda, as the case may be, are produced and glycerin is set free. On decomposing either of these compounds with sulphuric acid a sulphate of the alkali is formed, and the fatty acid is precipitated. Some of the fatty acids, as stearic, cerotic, palmitic, and lauric, are solid at ordinary temperatures; others, as oleic, are liquid. The hard fatty acids are extensively used as candle materials, being superior in every respect to the natural fats from which they are derived.

FAT′TENING. Until comparatively a recent date, the plan used to fatten domestic animals was to prevent their taking exercise, and to gorge them with food. The excessive fat produced by these means was, however, found to be far from wholesome, and was less delicate than that arising in the natural way. This system was therefore gradually abandoned in favour of the present one, which consists in supplying the animal with abundance of wholesome food, and with the means of taking exercise as far as the disposition or feelings dictate. Hence the farmers “in the most enlightened districts, such as Berwickshire, East Lothian, &c., instead of tying up their fattening cattle in stables like horses, and placing their food before them, put two or three together in small yards with sheds attached, in which they can run about, eat when they choose, and take shelter from the rain, or cold, or the sun, at pleasure, under the open shed. Swine are treated in the same manner, and also spring lambs that are fattened for the market. Poultry are no longer kept in coops and crammed, or rabbits in hutches; but the former are allowed to take exercise in fields sown with various herbs, and the latter are kept in a species of artificial warren, where they can take exercise by burrowing.” (Loudon.)

FAVOURITE PRESCRIPTION (Dr Pierce’s) for the cure of those chronic weaknesses and complaints peculiar to females. 280 grammes of a turbid greenish-brown fluid with a bulky deposit of the same colour, made according to the following recipe:—Savin tops, 10 grammes; larch agaric and cinnamon, of each 5 grammes; China Jaën (ash cinchona bark), 10 grammes; boil with sufficient water to make 220 grammes when strained. Dissolve in the filtrate gum Arabic, 10 grammes; white sugar, 5 grammes; and add tinct. digitalis and tinct. opii, of each 2 grammes; star anise oil, 8 drops; 90 per cent. spirit, 45 grammes. (Hager.)

FEAR. Although fear is a depressing and debilitating emotion, and sometimes acts prejudicially on the health, it frequently acts as a curative or preventive of disease. It is a well-known fact that females who are the most faint-hearted and desponding during the period of their sex’s trial, generally experience a more rapid convalescence than those who are more confident and resolute. During the raging of an epidemic fear generally induces temperance, cleanliness, and the adoption of other precautions which tend powerfully to prevent disease. Boerhaave, according to Pereira, is said to have prevented the occurrence of epileptic attack (brought on by the sight of a person falling down in a fit in the sight of the hospital patients), by directing a red-hot iron to be applied to the person who should next be affected.

FEA′THERS. Ostrich feathers are those most esteemed as articles of personal decoration, and goose feathers for beds; but the feathers of other birds are commonly used for both purposes.

Feathers are prepared for ornamental purposes by scouring them with white soap-and-water (1 oz. to the pint), used hot; they are next well rinsed in several successive portions of pure water, and after being drained and shaken, are, lastly, passed through water slightly blued with pure indigo, and dried out of the dust. When dry, the ribs are generally rubbed with a piece of glass, having a curved notch in it, for the purpose of increasing their pliancy, and the filaments are curled by drawing them, between the edge of a blunt knife and the ball of the thumb of the hand which holds it.

Feathers, Bleaching of:—

A new trade has sprung up within the past ten years, by which black, brown, or grey feathers are bleached sufficiently to enable them to be dyed any required colour.

The process is as follows:—The feathers are first thoroughly washed with soap-and-water, to free them from any oil they may contain. They are next transferred to a bath composed of bichromate of potash dissolved in water, to which has been added a few drops of nitric or sulphuric acid. In this bath they rapidly lose their black, brown, or grey colour, and become almost white. On being removed from this bath they are well rinsed in water, and are then fit to be dyed, even the most delicate colour. Great care is required in the process, as the flue of the feather is apt to be destroyed, if kept too long in the bath. A bleached feather may be readily known by the yellow colour of its stem.

Other methods have been adopted, such as a bath of chloride of lime, peroxide of hydrogen, or sulphurous acid, &c., but the bichromate bath gives the best results.

Feathers, Dyeing of:—

Black. By immersion for 2 or 3 days in a bath (at first hot) of logwood, 8 parts, and copperas or acetate of iron, (about) 1 part.

Blue. With the indigo vat.

Brown. By any of the brown dyes for silk or woollen.

Crimson. A mordant of alum, followed by a hot bath of brazil wood, and afterwards by a weak one of cudbear.

Pink or Rose. With safflower and lemon juice.

Plum. The red dye, followed by alkaline bath.

Red. A mordant of alum, followed by a hot brazil-wood bath.

Yellow. From an alum mordant, followed by a bath of turmeric or weld. Other shades may be obtained by a mixture of the above dyes.

Feathers may also be dyed by simple immersion, for two or three minutes, in a bath of any of the aniline colours.

Goose feathers for BEDS are generally PURIFIED by simply exposing them to the sun or in a stove until perfectly dry, and then beating them to remove loose dirt. When carelessly collected and dirty, they are sometimes first cleansed with lime water, or, better still, with a weak solution of carbonate of soda, or water to which a little solution of chloride of lime has been added; after which they are rinsed in clean water, and dried or stoved as before. Old feathers are cleansed or purified in the same way.

FEB′RIFUGES. Syn. Febrifuga, L. In pharmacy, substances or agents which cure or alleviate fever. The term is more particularly applied to medicines used against the ague, as CINCHONA BARK and ARSENIOUS ACID, and their preparations. The extreme value of cold water, as a drink in ardent fever, has been known in all ages. In 1723 Dr Hancocke published a work entitled—‘Febrifugum Magnum, or Common Water the best Cure for Fevers, and probably for the Plague,’ which in a short time ran through several large editions, but appears to have been overlooked by the hydropaths of the present day.

FEC′ULA. Syn. Fæcula, L. The matter which subsides from cold water in which bruised or rasped vegetable substances have been washed. The fecula obtained from the seeds of the cereals and leguminosæ, and from tuberous or bulbous roots, consists of nearly pure STARCH. In some cases the starch is associated with the green colouring matter (CHLOROPHYLL) and the narcotic principles of the vegetables which yield it. The green fecula obtained by straining the expressed juices of the leaves and herbaceous parts of plants is of this character.

The fecula of all the amylaceous roots, rhizomes, and tubers, may be easily obtained, on the small scale, by rasping them, pressing, and working the pulp in cold water, and after straining the resulting milky liquid through a hair sieve, allowing it to settle. The sediment may be again washed by diffusion through clean cold water, and must be, lastly, collected, and dried out of the dust, and, without artificial heat.

The fecula of narcotic plants for medicinal purposes is obtained by allowing the expressed juice to repose for 24 hours, and then decanting the clear portion, and drying the residue. Sometimes heat is employed. See Arrow-root, Starch, &c.

FEEDING BOTTLES. We extract from ‘The Sanitary Record’ the following valuable paper on ‘Feeding Bottles,’ by Dr Eustace Smith, assistant-physician to the City of London Hospital for Diseases of the Chest, and Physician to the East London Hospital for Children:—“In the artificial rearing of infants it is of importance that food should be given to them from a feeding-bottle. By this means the natural method of taking nourishment is imitated; the muscles of the mouth and cheeks are brought into play; and the secretion of saliva—a secretion which, very scanty at birth, becomes gradually more copious and takes so active a part in digestion—is encouraged and increased.

“Almost all babies will take their food more readily by this method, their instinct teaching them to suck everything that is put into their mouths. Even in cases where a deficiency in the hard palate presents so great an obstacle to sucking, on account of the impossibility of creating the necessary vacuum in the mouth, the difficulty can be overcome by a simple mechanical contrivance. Therefore, in every case of hand-feeding, a suitable bottle is the first thing to be desired.

“To be satisfactory a feeding-bottle must fulfil three indispensable conditions: it must be simple in construction and easily manageable; it must be capable of being readily cleaned; and in its use the milk must flow easily and without great effort on the part of the infant. The ordinary feeder in use at the present time consists of a flattened glass flask, closed at the mouth by a cap, which fits over the neck. A caoutchouc tube passes through the cap, and is connected inside the bottle with a straight glass pipe. The other end of the elastic tube is attached to the teat, or mouth-piece, by means of a short hollow cylinder called the ‘union-joint.’ The teat is firmly fixed to this by means of the shield. In the construction of the cap and union-joint, metal, earthenware, or wood, is employed. The metal used by the best makers is tin, and this, if cleanliness be properly attended to, is not objectionable. In cheaper bottles, sold in the shops for sixpence, the mouth is closed by a perforated cork, through which the flexible tube passes. Here there is no cap, but in all essential points the construction is the same as in the more expensive articles.

“In this apparatus it is important that the channel through the tubes should be perfectly free. The point at which the channel is narrowest is the union-joint, which connects the mouth-piece with the flexible tube. In a badly made bottle an impediment may exist at this point from carelessness in the manufacture, and may present a great obstacle to the ready passage of the fluid. Care also should be taken that the flexible tube passes completely through the cap, before it becomes connected with the glass pipe. This is very important. In the early feeding-bottles constructed upon this model by O′Connel, the glass pipe passed from within the bottle through the cap, and was attached outside this to the caoutchouc tube. It was thus held rigidly in the centre of the bottle, and as a natural consequence, when the apparatus was in use, unless the bottle was held upright during the whole meal, long before its contents were exhausted the milk ceased to flow, as the end of the pipe soon came to be above the surface of the fluid, which necessarily gravitated to the lowest part as the bottle lay on its side.

“When, however, the connection between the two tubes is made within instead of outside the bottle, this disadvantage no longer exists, for the glass tube being free to move, its end is able to sink to whichever side of the bottle is undermost, and therefore always remains below the level of the fluid. The best bottles have a small cylindrical stop, i.e. a thick ring of metal or wood placed within the flexible tube, just above its junction with the glass pipe. The object of this is to prevent the latter being drawn through the cap, and thus held rigidly in the centre of the bottle.

“The method of connection of the cap with the neck of the bottle is not unimportant. It should not be too tight or air will be prevented from entering the bottle to supply the place of the milk which is withdrawn. A common plan is to line the interior of the cap with cork, but this substance, besides its risk of being broken and detached by careless handling, has the further disadvantage of absorbing milk, which turns sour and may afterwards set up fermentation in fresh milk put into the bottle for a subsequent meal. In the best bottles the cap is constructed to screw on to the neck, as in the ‘Alexandra’ Feeding bottle made by the Messrs Maw; or is united to it by an application of the ‘bayonet catch,’ as in the ‘Improved’ feeding-bottle made by Messrs Lynch and Son. In this very admirable apparatus three grooves in the inside of the cap pass over corresponding projections on the neck of the bottle; the cap is then turned to the right, with a slight screwing motion, and becomes securely fastened.

“With badly made bottles infants often have very great difficulty in drawing up the milk, and can only do so by violent efforts, which soon exhaust their strength or their patience. There are two reasons why milk in these cases may not flow easily—either the cap fits too tightly, so that air cannot enter with sufficient facility in proportion as the liquid contents become diminished, as has just been mentioned; or the caoutchouc forming the flexible tube is too thin, so that it collapses when suction is applied. In the first case a small hole should be made through the cap, so as to allow a free admission of air, or if the bottle be a simpler one, closed at the mouth by a perforated cork, this may be slightly eased at the neck of the bottle, so as to fit less closely. In the second case, stouter caoutchouc should be used in the construction of the tube. In weakly infants, or those much reduced in strength by acute disease, special attention should be paid to these points, as such children will often refuse to take the bottle, if they find any difficulty in drawing up the milk.

“Infants born with a cleft palate cannot suck from an ordinary bottle, as the deficiency in the hard palate prevents the necessary vacuum being formed in the mouth. Such children are, therefore, usually brought up with a spoon, and often waste and die through insufficient nourishment. An ingenious contrivance first suggested by Mr Oakley Coles will, however, entirely remove the difficulty, and enable them to suck with as much ease as if they suffered from no such congenital difficulty. The plan is a very simple one, and consists in attaching to the nipple of any ordinary feeding-bottle a flap of sheet elastic, cut to fit the roof of the mouth. This flap must be of the shape and about the size of the bowl of a teaspoon, and is to be sewn to the upper part of the stalk of the teat, where this projects from the shield. In the mouth of the child the flap forms an artificial palate, which if the sheet elastic chosen be sufficiently stout, offers firm resistance to the tongue pressing against in sucking, and prevents fluid from passing into the nose in the act of swallowing.

“The closest attention must be paid to the cleaning of feeding-bottles. Each time after being used the whole apparatus should be well washed out with water containing a little soda in solution.

“The inside of the cap must be carefully cleaned, and the brush should be carried several times through the whole length of the tubing. Afterwards the bottle and tubes should be laid in cold water until again wanted. An objection to the common brush usually supplied with each feeder is, that after a few days’ use the softened bristles are apt to get detached and be caught in the joints of the tubing, whence they may afterwards be washed by the stream of fluid and be swallowed by the child. Accordingly, a new cleaner has been manufactured by Messrs Maw and Sons, in which bristles are entirely dispensed with. They are replaced by a thin strip of caoutchouc, which is wound round in a spiral form, at the end of the ordinary wire handle. This instrument answers all the purposes of a brush, without the disadvantages alluded to, and is besides far more durable.

“Excellent feeding-bottles are now made by many different manufacturers, and are sold at prices which place them within the reach of the poorest. These cannot all be mentioned, but some of the bottles more commonly met with, may be shortly referred to. The six-penny feeder made by Messrs Maw, Son, and Thompson, can be recommended for its simplicity of construction, and at the same time for its perfect efficiency. In this instrument there is no cap, instead the mouth of the bottle is closed by a cork, which is perforated for the passage of the flexible tube. In all other respects the construction of this apparatus is the same as in the more expensive instruments. The ‘Alexandra’ feeding-bottle, price half-a-crown, by the same makers, is an admirable bottle. The cap screws on to the neck, and is furnished with a small hole for the admission of air. A ‘stop’ in the lower part of the flexible tube prevents the glass pipe being drawn into the cap, and the instrument is supplied with all the latest improvements. The bottles made by Messrs Maw are all furnished with the new patent cleaner just described. The improved feeding-bottle made by Messrs Lynch and Son, at one shilling and eighteen pence, has been before referred to. The material used for the cap is boxwood. It is a capital bottle, and will give the fullest satisfaction to the purchaser. Mr Lang’s ‘Alma Mater’ feeding-bottle can also be recommended. In this instrument the cap is made of earthenware and is lined with cork. A good bottle is made by Mr Elam, of Oxford Street, price two shillings; the cap is formed of britannia metal, and screws on to the neck. A cheaper bottle, but one which for elegance of design and accuracy of detail cannot be surpassed, is Mr Mather’s ‘Princess’ feeding-bottle. A tin cup screws on the neck, and is pierced by a small hole for the admission of air. The opening is fitted with a ‘cone valve’ of simple and ingenious construction, which allows air to enter freely when suction is applied to the tube, but closes firmly against any escape through the air-hole of the fluid contents of the bottle. The bottle itself has a double curve towards the neck to provide against too sudden bending of the flexible tube against the tap. This is apt to happen when the curve is single, if the bottle lie with the convexity downwards, and partial obstruction of the tube may be the result. The ‘Princess’ feeding-bottle is sold in the shops for eighteen pence.

“All bottles bear their name in raised letters upon the glass, but a report which has obtained currency that these letters are hollow in the interior, and difficult to cleanse is without any foundation in fact. Any one may test this for himself by placing a finger within the bottle underneath the letters, when the internal surface will be found perfectly plain and uniform. In all cases where cork enters into the construction of a feeding-bottle, especial care should be taken in cleansing the apparatus, and the cork should be well soaked in soda and water in order that any sour milk it may contain may be neutralised at once.”

FEET (The). To preserve the feet in a proper condition, they should be frequently soaked, and well washed in warm or tepid water. The nails of the toes should be pared, to prevent their becoming inconveniently long, and from growing into the flesh, soaked, and well washed in warm or tepid water. Many persons suffer severely from TENDER FEET. This generally arises from the use of thin cotton or silk stockings, and boots or shoes that are either too tight or stiff, or not sufficiently porous to permit of the escape of the perspiration. Waterproof boots and shoes which are also air-tight (as those of gutta percha and India rubber), are common causes of tender feet, and even of headaches, dyspepsia, and apoplexy. The best treatment of tender feet is the immediate adoption of worsted stockings or socks, and light, easy shoes of buckskin, goatskin, or some other equally soft kind of leather. It is highly necessary for the preservation of health to preserve the feet DRY; persons who are, therefore, exposed to the wet, or who are frequently passengers through the public streets in bad weather, should regard sound and good boots and shoes as of the first importance. In fact, in a hygienic point of view, a wet back should be less shunned than wet feet. Many persons frequently experience EXTREME COLDNESS and NUMBNESS OF THE FEET. The best and most natural remedy for this is active exercise or friction, the former being always adopted when possible. In such cases the use of warm woollen stockings is absolutely necessary, and the debilitated and aged may advantageously keep them on throughout the night, or at all events until the feet acquire a comfortable degree of warmth. The DISAGREEABLE ODOUR which is evolved by the feet of some individuals in hot weather may be removed by the observance of extreme cleanliness, and by occasionally soaking the feet in warm water, to which a small quantity of chloride of lime or sal ammoniac has been added. A good deodoriser for unpleasant smelling feet is said to be the following, invented by M Paulcke:—A mixture of equal parts of salicylic acid, soap, talc, and starch, to be applied in the form of powder.

Distortion of the feet is not uncommon in childhood, being sometimes congenital, but as frequently the result of weakness or bad nursing. “A child with its feet turned inwards is called VARUS; when they are turned outwards it is styled VALGUS. The proper use of bandages, early applied, will generally correct these deformities; but if they be neglected in infancy they become incurable.” (‘Med. Lex.’) Clubfoot, of which there are several varieties, may also be frequently relieved by a simple surgical operation. See Boots and Shoes, Distortions.

FELT′ING. This is a process by which various species of fur, hair, and wool, are blended into a compact texture, in many respects resembling cloth. It depends on the peculiar anatomical construction of these substances, enabling them to interlace and intertwine with each other, by which they become permanently matted together. Felt was formerly chiefly employed for hats. It is now commonly used for mill-bands, filters, &c.; and when varnished or japanned, or saturated with asphalte or bitumen, is a durable substitute for japanned leather, and for roofing.

FENNEL. Syn. Fœniculum (Ph. L.), L. The fruit (seed) of Fœniculum dulce, or sweet fennel; the oil distilled from the fruit (OIL OF FENNEL; OLEUM FŒNICULI, L.) as well as a distilled water (FENNEL WATER; AQUA FŒNICULI, L.), are officinal in the Pharmacopœias. They are stimulant and carminative; but are now seldom employed.

FEN′UGREEK. The seeds of Trigonella Fœnum Græcum. Resolvent and stomachic. The seeds dye yellow; formerly roasted for coffee; now chiefly employed in veterinary medicine.

FER′MENT. Syn. Fermentum, L. A substance which induces fermentation. According to one view ferments are compounds whose decomposition proceeds simultaneously with that of the body undergoing metamorphosis. They all contain albuminous or azotised principles, which in a moist state putrefy and suffer decomposition. According to Pasteur, however, fermentation is excited by living organisms—fungi and infusoria. See Fermentation and Yeast.

FERMENTA′TION. Syn. Fermentatio, L. In chemistry, a peculiar metamorphosis of a complex organic substance, by a transposition of its elements under the agency of an external disturbing force. Fermentation, according to the theory proposed by Liebig, is a metamorphosis, by which the elements of a complex molecule group themselves so as to form more intimate and stable compounds. It is excited by the contact of all bodies the elements of which are in a state of active decomposition or fermentation. “In nitrogenised substances of a very complex constitution, putrefaction or fermentation is spontaneously established when water is present, and the temperature sufficiently high, and it continues till the original compounds are wholly destroyed. Substances destitute of nitrogen, on the contrary, require, in order to their undergoing this metamorphosis, the presence of a nitrogenised substance, already in a state of putrefaction (fermentation).” (Liebig.) The substances which promote this change are termed FERMENTS, and among these the principal are gliadin, gluten, vegetable albumen, and all nitrogenous substances in a state of spontaneous decomposition or fermentation. “It is imagined that when these substances, in the act of undergoing change, are brought into contact with neutral ternary compounds of small stability, as sugar, the molecular disturbance of the body, already in a state of decomposition, may be, as it were, propagated to the other, and bring about the destruction of the equilibrium of forces to which it owes its being. The complex body, under these circumstances, breaks up into simpler products, which possess greater permanence.” (Fownes.) Yeast, the ferment most commonly employed for inducing the vinous fermentation, is such a substance in an active state of putrefaction, and whose atoms are in continual motion. Putrefying animal substances are equally capable of exciting the same action. “If we add to a solution of pure sugar an albuminous substance, a caseous or fleshy matter, the development of yeast becomes manifest, and an additional quantity of it is found at the end of the operation. Thus, with nourishment, ferment engenders ferment. It is for this reason that a little fermenting must, added to a body of fresh grape juice, excite fermentation in the whole mass. These effects are not confined to alcoholic (vinous) fermentation. The smallest portion of sour milk, of sour dough, or sour juice of beet-root, of putrefied flesh and blood, occasions like alterations in fresh milk, dough, juice of beet-root, flesh, and blood. But further, and which is a very curious circumstance, if we put into a liquid containing any fermenting substance another in a sound state, the latter would suffer decomposition under the influence of the former. If we place urea in the presence of beer-yeast, it experiences no change; while if we add it to sugar-water in a fermenting state, the urea is converted into carbonate of ammonia. “We thus possess two modes of decomposition; the one direct, the other indirect.” (Ure.)

A very remarkable circumstance connected with fermentation is that it is always accompanied by the development of microscopic living organism—fungi and infusoria. “So constantly, indeed, is this the case, that many chemists and physiologists regard these organisms as the existing cause of fermentation and putrefaction; and this view appears to be corroborated by the fact that each particular kind of fermentation takes place most readily in contact with certain living organisms.” (Fownes.) Thus the vinous or alcohol-producing fermentation is accompanied, or caused, by two fungi, called Torula cerevisiæ and Penicillium glaucum; the acetous or vinegar-producing fermentation by Torula aceti; the lactous fermentation (souring of milk) by Penicillium glaucum.

The butyric fermentation by an animal—an infusorium, which cannot exist in free oxygen, but flourishes in an atmosphere of hydrogen, &c.

Of late years these latter views as to the cause of fermentation have been accepted by most of the scientific world, notwithstanding the opposition they experienced from so powerful an antagonist as Liebig.

From the researches of Pasteur, the distinguished author of the modern theory of fermentation, as opposed to the chemico-physical theory of Liebig, it appears that when yeast is placed in a solution of sugar and water, or in a solution of sugar and water containing albuminous substances, under proper conditions as to temperature, the fermentation that ensues is due to the process of growth taking place in the yeast plant; the new cells of which, in assimilating part of the sugar and converting it into cellulose and fat, cause, at the same time, the breaking up of the sugar molecule, and resolve it into the more stable combinations of alcohol and carbonic acid.

In order that the ferment or fungus should grow it is essential that, in addition to the cellulose and fat, it should be supplied with ammoniacal salts and soluble phosphates. These are generally present in the liquid about to be fermented; but when yeast is added to pure sugar and water “it lives at the expense of the sugar, and of the nitrogenous and mineral substances contained within itself.”

Speaking of the influence of oxygen on the development of yeast on alcoholic fermentation, Pasteur states that ready-formed yeast can germinate and grow in a liquid containing sugar and albuminous matters, even when oxygen is completely excluded. The quantity of yeast formed, however, in this case, is but small, and the fermentation goes on slowly; nevertheless, a large quantity of sugar disappears (sixty to eighty parts to one part of yeast). If the air has access to a large surface the fermentation goes on quickly, and a much larger quantity of yeast is formed in proportion to the quantity of sugar which disappears.

In this case, also, oxygen is absorbed by the yeast, which grows quickly, but does not act so decidedly as a ferment, inasmuch as only four to ten parts of sugar disappear for one part of yeast produced.

When the air is excluded the same yeast again acts as a powerful ferment. Pasteur, therefore, infers that yeast which acts as a ferment in the absence of air abstracts oxygen from the sugar, and that upon this deoxidising power its action as a ferment depends. The violent activity of the yeast at the commencement of the fermentation is due to oxygen dissolved in the liquid. In liquids containing albumen (yeast and water, &c.) yeast likewise grows, though sparingly, even if the solution does not contain a trace of sugar, provided there is a sufficient access of air. But if the air is excluded this does not take place, even though the liquid may contain, besides albumen, a non-fermentable sugar, such as milk sugar. The yeast formed in a liquid not containing sugar possesses all the properties of a ferment, and excites fermentation in a solution of sugar excluded from the air.

Similarly, Pasteur regards putrefaction as a kind of fermentation, set up and maintained by an animal organism, or ferment belonging to the genus Vibrio. Putrefaction, when taking place in contact with the air, is always accompanied by decay or EREMACAUSIS. The abandonment of the old theory as to the nature of eremacausis, viz. that it consisted in the gradual combustion of decaying organic matters by atmospheric oxygen, has been necessitated by the experiments of Pasteur, Schröder, and others, which have conclusively established the facts that organic substances are not oxidised by perfectly pure air, and that their decomposition and subsequent destruction are due to the presence in the air of the sporules or seeds of certain low organisms. Pasteur cites numerous instances corroborative of the statement that perfectly pure oxygen fails to affect, save to a very limited extent, organic substances.

In one case an aqueous infusion of yeast mixed with sugar was enclosed in a sealed flask with double its volume of air, which had been previously depurated by being made to pass through a red-hot tube. At the end of three years the liquid (which had during part of the time been kept at a temperature of from 25° to 30° Cent.) was found to be perfectly fresh and transparent, and the air when examined gave 18·1 vols. of oxygen, 80·5 vols. of nitrogen, and 1·4 of carbonic acid. Under the same conditions urine and milk, whether fresh or previously boiled, showed minute traces only of oxidation; crystals of uric acid and phosphates formed in the urine, but the milk was unaltered, having preserved its alkaline reaction, and showed no disposition to curdle.

Very different, however, was the result when either of the above substances was enclosed with ordinary air. It was then found that in a few days the whole of the oxygen was absorbed, carbonic acid being at the same time simultaneously formed. A certain quantity of moistened oak sawdust kept in contact with ordinary air for a fortnight was found at the end of that time to have absorbed 140 cubic centimètres of oxygen; whilst the same amount of sawdust enclosed with an equal volume of purified air had removed only a few cubic centimètres of the gas in a month. In the former experiment a microscopic film of mycelia and spores of Mucidineæ formed on the sawdust.

From numerous experiments of a like nature with the above, and attended with analogous results, chemists and physiologists now generally regard eremacausis as effected by agencies similar in character to those which produce fermentation and putrefaction.

“The observations of Schröder upon the processes of fermentation and putrefaction are remarkable. He has shown that any organic liquid may be prevented from fermenting or putrefying if it be heated under pressure to about 266° F. (130° C.), then transferred to a flask and boiled, the mouth of the flask being plugged whilst boiling with a pellet of cotton wool, which is left in the neck of the flask. In this way he preserved, during a hot summer, various liquids, including freshly-boiled wort, blood, white of egg, whey, urine, broth, and milk; but when afterwards the plug of cotton wool was withdrawn these liquids in a few days began to undergo decomposition. He explains these results by supposing that the spores of some organism must find access to the substance in order to set up the process of decomposition. By a temperature of 260° F. (126·7° C.) any such spores which the substance itself might contain are destroyed, and as the air is filtered through the cotton wool before it reaches the interior of the flask, none of these organic germs can afterwards gain access to the body under experiment. I have repeated some of these experiments with complete success.

“If air be transmitted with suitable precautions slowly through narrow ignited platinum tubes, so as to destroy all suspended organic particles, no fermentation or putrefaction will take place on admitting such air into contact with putrescible substances previously heated to 260° for an hour.”

Pasteur has shown the existence of these floating germs in the air by drawing a large volume of atmospheric air, by means of an aspirator, through a narrow tube obstructed by collodion wool. On subsequently dissolving this wool in a mixture of alcohol and ether various microscopic sporules were left undissolved.

The entire absence of the exciting causes—warmth, air, and moisture—leaves even those substances which under ordinary circumstances are most liable to change, in a state in which they may remain for an almost indefinite period without perceptible alteration. Thus, animal substances in a frozen or dry state do not undergo decomposition, nor does a solution of sugar or the juice of grapes (must) when perfectly excluded from the air; but on the mere exposure of these substances to warmth, moisture, or atmospheric air, putrefaction or fermentation immediately commences. Remove the cork from the bottle of ‘capillaire’ on the parlour sideboard, or pierce the skin of one of the grapes on the dessert table with a needle, and these bodies, which would have otherwise suffered no change for weeks, or even months, will soon exhibit symptoms of spontaneous decomposition. The knowledge of this fact has been practically applied to the preservation of animal and vegetable substances for food. Even the most putrescible of these may be preserved for an unlimited period by enclosure in metallic cases, or glass bottles, from which the air has been completely removed and excluded.

The important duties which fermentation or putrefaction performs in the economy of our globe, and in several of the arts of life and civilisation, have long rendered the development of its principles an object of the highest interest and importance, both in a scientific and practical point of view. In its most extended sense, this subtile process of nature, though occasionally productive of injurious effects, may be regarded as one of the most necessary and beneficial with which we are acquainted. Like the labours of a scavenger, it speedily removes from the surface of our globe those matters which would otherwise remain for some time without undergoing decomposition. It either dissipates in air, or reduces to more fixed and useful forms of matter, those organic substances which, by their presence, would prove noxious, or, at all events, useless to the animal and vegetable kingdoms. It is the giant power that cleans the Augean stable of nature, at the same time that it provides some of the most esteemed articles of utility and luxury for the well-being and enjoyment of man.

Chemists have distinguished fermentation into different varieties, which, in general, are named after the more important products of its action. Of late years, the number of these varieties has been greatly increased by the extension of the term to several operations besides those formerly included under it. See Acetification, Bread, Putrefaction, Brewing, &c.

FERN (Male). Syn. Male shield fern, Filix mas, Radix filicis, L. The root (rhizome) of the Lastræa Filix-mas, or male fern. It is bitter, astringent, or vermifuge.—Dose, 1 to 3 dr. in powder, or made into a decoction, repeated for 3 or 4 days, and followed by a purge. It is chiefly given in tapeworm. In Switzerland it is deemed almost infallible, but has proved less successful in these countries. See Oils.

FERRICY′ANIDE. Syn. Ferridcyanide, Ferridcyanuret. A compound of ferricyanogen with a metal or other basic radical. The FERRICYANIDE OF POTASSIUM, or ‘RED PRUSSIATE OF POTASH,’ as it is often improperly called, is a well-known example. The ferricyanides of AMMONIUM and the ALKALIES and ALKALINE EARTHS are soluble; those of most of the METALS, insoluble. See below.

FERRICYAN′OGEN. Syn. Ferridcyanogen, Ferric-cyanogen. The peculiar salt-radical which exists in the so-called red prussiate of potash. It is isomeric with ferrocyanogen, from which it differs in capacity of saturation (being tribasic), and in the behaviour of its compounds with solutions of the metals. It has not been isolated. See Potassium (Ferricyanide).

FERROCY′ANIDE. Syn. Ferrocyanuret, Prussiate; Ferrocyanidum, Ferrocyanuretum, L. A compound of ferrocyanogen with a metal or other basic radical. The principal substance of this kind is the FERROCYANIDE OF POTASSIUM or ‘YELLOW PRUSSIATE OF POTASH,’ as it is often called. See the respective basis—Ammonium, Potassium, Sodium, &c., and below.

FERROCYAN′OGEN. Syn. Ferrocyanogenium, L. A bibasic salt radical, composed of the elements of 3 equivalents of CYANOGEN and 1 equivalent of the metal IRON. It has never been isolated. It unites with the various bases to form FERROCYANIDES. See Cyanogen, Hydroferrocyanic Acid, Iron, &c.

FERRU′GO. [L.] Rust of iron. See Iron (Sesquioxide).

FE′VER. Syn. Febris, Pyrexia, L. In pathology a condition characterised by loss of appetite, thirst, languor, debility, unwillingness to move, accelerated pulse, increased heat of surface, and general disturbance of all the functions. A large number of diseases in which all or some of these symptoms appear are called FEVERS. They have been divided by nosologists into intermittent (INTERMITTENTES), remittent (REMITTENTES), and continued fevers (CONTINUÆ). The first of these are generally known as AGUES; the second differ from agues in there being one or more marked exacerbations and remissions of the symptoms every 24 hours, but without any entire intermission. The terms ‘hectic,’ ‘nervous,’ ‘bilious,’ ‘inflammatory,’ &c., have also been applied to particular varieties of fever; and names indicative of certain cutaneous appearances connected with them have been given to others; as ‘scarlet’ fever, ‘yellow’ fever, &c.

The usual symptoms of incipient fever (febrile symptoms) are—chilliness (varying from a simple shiver to a sensation of cold water running down the back), a quick pulse, hot and dry skin or flushing, languor, often evinced by yawning, depression of spirits, alternate fits of shivering and heat, hurried and uneasy respiration, flying pains in various parts of the body, as the head, back, and loins; loss of appetite, nausea or vomiting, dry mouth, furred tongue, costiveness, urine small in quantity, and usually of a deep colour, &c. When any of these symptoms appear, their progress may often be arrested by the timely exhibition of an emetic, followed by a saline purgative, and diaphoretics; at the same time promoting the action of these remedies by a low diet and drinking copiously of diluents, and carefully avoiding animal food, spirits, fermented liquors, or anything at all stimulant. Whenever symptoms of fever become established, medical advice should be sought and implicitly followed. In parts where it cannot be obtained the treatment recommended under Ague, Inflammation, Remittent Fever, and Typhus, may be followed with advantage.

In visiting or attending persons labouring under fevers, it is advisable to avoid immediate contact with them or their clothing, or standing near them in such a position as to inhale their breath, or the effluvia evolved (in some cases) by their bodies; and when remaining for some time in the apartment it is preferable to sit or stand near the fireplace, or between the window and door, as such parts of the room are generally better ventilated than the other portions. The greatest purifier of the atmosphere of a sick chamber is a good fire, because it occasions a continual current of the impure air up the chimney, and a corresponding influx of fresh air from without. Chloride of lime, or chloride of zinc, or their solutions, are also good purifiers. The first, however, should not be used in quantity, as the evolved chlorine might in that case impede the respiration of the patient. It is also advisable to avoid entering the room of a patient labouring under contagious diseases of any class when the stomach is empty or the spirits depressed; and it has been recommended to clear the mouth of the saliva immediately after quitting the chamber. See Ablution, &c.

FEVER DROPS (C. Warburg’s Vegetable). Camphor and aloes, 2⁄2; orange peel, 10; elecampane root, 12; digest with 90 per cent. spirit 240, mixed with ac. sulphuric dil. 24. To the tincture add quinine sulphate 9; tinct. opii crocatæ, 2⁄2. (Ragsky.)

FEVER POWDERS (James’s, also called James’s Powder and Pulvis Jacobi). It consists essentially of phosphate and antimoniate of lime with free antimonic acid.

FEVERSTONE—Lapis Anti-febrilis—Fieber Stein. Lead oxide, 54 parts; arsenic acid, 46 parts; melted together. (Winckler.)

FI′BRIN. Syn. Fibrine. An azotised substance, forming the coagulable portion of fresh-drawn blood, and the principal constituent of the muscular or fleshy parts of animals. It is eminently nutritious, and capable of yielding in the animal body albumen, caseine, and the tissues derived from them. (Liebig.)

Prep. Fibrin is easily obtained in a nearly pure state, by agitating or beating newly drawn blood with a small bundle of twigs, when it attaches itself to the latter under the form of long reddish filaments, which become white when worked with the hands in a stream of cold water. It may also be procured by washing the coagulum of blood, tied up in a cloth, in cold water, until all the soluble portions are removed. A small quantity of fat, which it still contains, may be removed by digesting it in ether.

Prop., &c. Pure fibrin occurs as long, white, elastic filaments, which are tasteless, inodorous, and insoluble in both hot and cold water. Wetted with acetic acid, it forms, after a time, a transparent jelly, which is slowly soluble in pure water. Very dilute solutions of the caustic alkalies dissolve it completely, and the new solution greatly resembles liquid albumen. Dried by a gentle heat it loses about 80% of water.

FICHTENNADEL-BRUSTZUCKER (Pine-needle Pectoral Sugar). (L. Morgenthau, Mannheim.) For irritable cough, hoarseness, tightness of the chest, asthma, stubborn lung affections, chronic catarrh, &c. Little sticks of bonbon, containing a very little opium, and wrapped in tinfoil. (Hager.)

FICHTENNADEL-TABAK (Pine-Needle Tobacco. (L. Morgenthau.) Is said to be patented in England. Ordinary tobacco moistened or sprinkled with a weak spirituous solution of wood wool extract and wood wool oil and dried; made up in cigars for smoking. (Hager.)

FIG. Syn. Ficus (B. P., Ph. L. E. & D.), Carica, Caricæ fructus, L. The figs of commerce are the dried fruit of Ficus Carica, the common fig-tree. They are demulcent, emollient, laxative, and pectoral. Roasted and boiled figs are occasionally employed as poultices to gumboils and other affections of the mouth.

FILARIA DRACUNCULUS. The Guinea worm. The female of this parasite is to be met with in tropical climates only, infesting the subcutaneous cellular tissue of man and some animals. In appearance it resembles a piece of white whip-cord of uniform thickness. According to Mr Ewart it varies in length from twelve and three quarters to forty inches, and is on an average twenty-five and a half inches long. It usually contains only one young worm, although rare instances have occurred in which as many as fifty of its progeny have been discovered in the same parent. In almost every case when this creature leaves the body, it does so by the lower extremities; occasionally, however, it does so by the mouth, the cheeks, or below the tongue. When the young of the guinea worm are placed in pure water they survive only four or five days; in foul water they will exist for three weeks. It appears that immersion in water, of the body of the person afflicted with the parasite, sometimes has the effect of inducing the creature to leave his human quarters, since Dr Lorimer states “that many people belonging to the bazaars in the vicinity of the lines, affected with the parasite, come, for the express purpose of extracting the worm, to the same tank where the men of the regiment bathe. The people so infested swim about in the water, with the worm hanging loose, drawing the limb quickly backwards and forwards, and from side to side, until the expulsion is affected.” Outside the body the guinea worm is generally found beneath organic débris in wells, tanks, and other reservoirs for water, from whence it appears to be now pretty universally admitted it effects an entrance through the skin during bathing or wading.

FILARIA SANGUINIS HOMINIS. In 1872, Dr T. R. Lewis, in examining microscopically the blood and urine of some of his patients in India, discovered a worm enveloped in an extremely delicate tube, closed at both ends, within which it could either elongate or shorten itself. This parasite (called from its principal habitat the Filaria Sanguinis Hominis) is about ⁄75th of an inch in length, and about ⁄35000th of an inch in diameter. When removed from the body with a small quantity of blood, it is described as being in a state of incessant motion, unceasingly coiling and uncoiling itself, lashing the blood-corpuscles in all directions, and insinuating itself between them.

The worms are said, when first taken from the body, to present a translucent appearance; the larger specimens, however, frequently exhibit an aggregation of granules towards the junction of the lower and middle half. Occasionally a bright spot, suggestive of a mouth, is seen at the thicker extremity. It is stated that they continue active from six to thirty hours. Mr Lewis does not believe they are able to perforate the tissues.

“These parasites,” says Mr Lewis, “are so persistently ubiquitous, as to be obtained day after day by simply pricking any portion of the body, even to the tips of the fingers and toes of both hands and both feet of one and the same person, with a finely pointed needle. On one occasion six excellent specimens were obtained in a single drop of blood by merely pricking the lobule of the ear.”

Dr Lewis estimates, from the number of the Filaria found in one drop of the blood of one patient, that his body must have contained more than 140,000. The presence of these creatures in the blood is believed to be the cause of chylous urine, which is a very common disease in the East. It seems probable they gain admission into the body from being present in drinking water.

FIL′BERT. Syn. Filberd. The fruit of the cultivated hazel or nut-tree (Corylus Avellana). Filberts are distinguished from common nuts by their lengthened figure and larger size. The best are imported from Spain.

FILES. The manufactures of these articles do not come within the limits of this work. It may, however, be useful to mention that FILES, FLOATS, and RASPS, which “cut dull” from age, dirt, or being much worn, are greatly improved by being kept wet, immersed in water for some hours, or even for a day or two.

Mr Ernest Spon recommends the following method for renovating files:—The file to be first cleansed from all foreign matter, and then dipped in a solution of one part of nitric acid, three parts of sulphuric acid, and seven parts of water; the time of immersion will be according to the extent the file has been worn, and the fineness of the teeth, varying from five seconds to five minutes. On taking it out of the mixture, wash in water, then dip in milk of lime, wash off the lime, dry by a gentle heat, rub over equal parts of olive oil and turpentine, and finally brush over with powdered coke.

FIL′TER. Syn. Filtrum, L. An instrument or apparatus for straining or filtering liquids.

FIL′TERING POWDERS. Prep. 1. Fuller’s earth washed, dried without heat, and reduced to coarse powder.

2. Pipe clay or potter’s clay, as the last. Both the above are used to filter and bleach oils.

3. Clay or fuller’s earth, 1 part; fine siliceous sand, 2 parts; the two are separately washed, after which they are drained, and mixed together, and dried as before. Used for GLUTINOUS OILS.

4. Granulated animal charcoal, sifted and fanned from the dust. Used to filter and bleach SYRUPS and VEGETABLE SOLUTIONS.

Obs. Filtering powders are prepared of several degrees of coarseness, and should be chosen with reference to the degree of fluidity of the liquid to be filtered through them. In no case should they be reduced to fine powder, as not only is the process of filtration thereby rendered unnecessarily tedious, but in some cases (as when charcoal dust is mixed with glutinous vegetable solutions and syrups) the filtrate carries off a portion of the powder, which can afterwards be separated from it only with considerable difficulty. See Charcoal, Filtration, Oil, &c.

FILTRA′TION. Syn. Filtratio, L. The separation of liquids from substances mechanically suspended in them, by passing them through media having pores sufficiently fine to retain or keep back the solid matter. Filtration is one of the most common and useful of the chemico-mechanical operations of the arts, and its successful performance in an economical and expeditious manner is therefore a matter of the highest importance in the laboratory, and, indeed, in almost every branch of human skill and industry, in which liquids are employed. Simple in principle, and apparently easily performed, it is, nevertheless, one of those operations which require no less of care than of tact and experience to conduct it with certainty and success. The losses sustained in the laboratory, by defective manipulation in this particular, often exceed those arising from ignorance and accidents in every other department conducted in it.

Filtration is generally resorted to for the purpose of freeing liquids from feculence, dirt, and other foreign matter, and for obtaining them in a clear or transparent state; but, in some cases, it has for its object the collection of the suspended substances, as precipitates, &c., and in others both these intentions are combined. The word ‘filtration’ is absolutely synonymous with ‘straining,’ but in the language of the laboratory it is usually applied to the operation of rendering liquids transparent, or nearly so, by passing them through fine media, as filtering paper, sand, and the like; whilst the term ‘straining’ is employed to designate the mere separation of the grosser portion, by means of coarse media, flannel, horsehair cloth, &c., through which they flow with considerable rapidity. Filtration is distinguished from ‘clarification’ by its mere mechanical action, whereas the latter operates by depuration, or the subsidence of the suspended substances or fæces, arising from their gravity being naturally greater than the fluid with which they are mixed, or being rendered so by the application of heat, or by the addition of some foreign substance.

The apparatus, vessels, or media, employed for filtration, are called ‘FILTERS,’ and are technically distinguished from ‘STRAINERS’ by the superior fineness of their pores.

Both strainers and filters act on the same principles as the common sieve on powders; they all, in like manner, retain or hold back the coarser matter, and permit the liquid or smaller and more attenuated particles to pass through. The term ‘medium’ (pleural ‘media’) is applied to the substance or substances through the pores of which the liquid percolates.

The form of filters, and the substances of which they are composed, are various, and depend upon the nature of the liquids for which they are intended. On the small scale, funnels of tin, zinc, copper, wedgwood-ware, earthenware, glass, or porcelain, are commonly employed as the containing vessels. (See engr.) The filtering medium may be any substance of a sufficiently spongy or porous nature to allow of the free percolation of the liquid, and whose pores are, at the same time, sufficiently small to render it limpid or transparent. Unsized paper, flannel, linen, calico, cotton wool, felt, sand, coarsely powdered charcoal, porous stone, or earthenware, and numerous other substances of a similar kind, are employed for this purpose.

For many liquids that filter easily, and in which the suspended matter is of a coarse and porous nature, it is often sufficient merely to place a little cotton wool or tow, or a small piece of sponge, in neck of the funnel, as at (a, fig. 1) in the above engr.; but such an apparatus, from the small extent of the filtering surface, acts either slowly or imperfectly, and soon gets choked up. Filters of unsized paper are well suited for all liquids that are not of a corrosive or viscid nature, and are universally employed for filtering small quantities of liquids in the laboratory. A piece of the paper is taken of a size proportionate to the quantity of the liquid to be filtered, and is first doubled from corner to corner into a triangle (see engr. a), which is again doubled into a smaller triangle b, and the angular portion of the margin being rounded off with a pair of scissors c, it constitutes a paper cone, which is placed on a funnel of proportionate capacity, and is then nearly filled with the liquid. A piece of paper so cut, when laid flat upon the table, should be nearly circular. Filtering paper is now sold ready cut in circles of various sizes, which simply require doubling for use. Another method of forming a paper filter, preferred by some persons, is to double the paper once, as above, and then to fold it in a similar way to a fan, observing so to open it and lay it on the funnel that a sufficient interval be left between the two to permit of the free passage of the filtered liquid on its descent towards the receiver. The ‘plaited filter,’ as thus formed, is exceedingly useful for general purposes; it exposes the entire surface of the paper to the liquid, and allows filtration to proceed more rapidly than a ‘plain filter’ does. (See Fig. 3.)

Mr Rother takes objection to the ordinary plain paper filter employed in the laboratory, because of the superfluous fold which in two thicknesses lies under one half of the extended surface of the filter. He says the interposition of these two extra layers compels the liquid to pass through three thicknesses of paper on the half side of the extended filter, whilst the other half side presents only a single thickness. It is evident that the two hidden layers are a very appreciable impediment to the current, aside from the more important fact that the liquid will traverse this side less rapidly than the other, and thus occasion an imperfect washing of the precipitate, or at least prolong the operation beyond reasonable limits. Recognising these objections to the old filter, Mr Rother has invented a very simple modification of the plain filter which, whilst saving 50 per cent. of the paper, he states, removes all the defects of the old form. This new filter practically presents but a single thickness of paper to penetrate, at the same time preserving an even surface, equal in all other advantages to the plain filter.

The filtrations are said to be more rapid than with the usual form, and the absence of the superfluous half sheet admits of more rapid drying.

To make the new filter:—Cut the circular disk of filtering paper in two through the line of its diameter, take either half disk, and fold it across the line of the radius, then turn down the double edge of the cut side and fold it over several times—finally, run a hard smooth surface along the seam thus produced, to compress it, and spread the finished filter into an appropriate funnel, first moistening it with water before the liquid to be filtered is poured in.

In reference to funnels, it may be remarked that those employed for filtering rapidly should be deeply ribbed on the inside, or small rods of wood or glass, or pieces of straw, or quills, should be placed between them and the paper. The neck or tubular part of the funnel should, in like manner, be deeply ribbed or fluted on the outside, to permit of the free passage of the air, when it is placed in a narrow-mouthed bottle or receiver. When this is not the case, filtration proceeds but slowly, and the filtered liquid is apt to be driven up the outside of the neck of the funnel by the confined air, and to be continually hissing and flowing over the mouth of the vessel. The breadth of a funnel, to filter well, should be about three fourths its height, reckoning from the throat (a). When deeper, the paper is liable to be continually ruptured, from the pressure of the superincumbent fluid; and when shallower, filtration proceeds slowly, and an unnecessarily large surface of the liquid is exposed to the atmosphere, and is lost by evaporation. To lessen this as much as possible, the upper edge of the glass is frequently ground perfectly smooth, and a piece of smooth plate-glass is laid thereon. When paper filters are of large dimensions, or employed for aqueous fluids that rapidly soften the texture of the paper, or for collecting heavy powders, or metallic precipitates, it is usual to support them on linen or calico, to prevent them breaking. This is best done by folding the cloth up with the paper, and cutting the filter out of the two, in the same way as would be done with doubled paper, observing so to place it in the funnel that the paper and calico may remain close together, especially towards the bottom.

The filtration of small quantities of liquid, as in chemical experiments, may often be conveniently performed by merely placing the paper on the circular top of a recipient (see engr.), or on a ring of glass or earthenware laid on the top of any suitable vessel. A filter of this kind that will hold one fluid ounce will filter many ounces of some liquids in an hour.

Good filtering paper should contain no soluble matter, and should not give more than ⁄250 to ⁄230 of its weight of ashes. The soluble matter may be removed by washing it, first, with very dilute hydrochloric acid, and secondly, with distilled water.

The ‘Munktell’ Swedish filtering paper is composed of flax fibres very much crushed and broken, and owes its value to the broken pieces of the fibres filling up the pores, and thus preventing solids from passing through the paper. Rhenish filtering paper is also made from flax, but in consequence of the more perfect condition of its fibres, is more porous than Munktell’s, and therefore inferior to it for filtering purposes. Another kind of Rhenish paper, also of flax, in which the fibres are much torn, is manufactured and is said to be a useful article, and to allow the rapid passage of fluids through it. The white filtering papers of English make have a small quantity of cotton mixed with the flax; and the fibres are much torn and crushed; hence they make serviceable filters.

The grey, circular cut filtering paper of varying sizes, of foreign make, as well as the grey sheet filtering paper of Dutch and English manufacture, contains a large quantity of wool, much of which is coloured; as well as jute and esparto grass, both of these latter in an unbleached state. The amount of ash in the Munktell paper has of late increased in quality.

For filtering a larger quantity of a liquid than can be conveniently managed with a funnel, and also for substances that are either too viscid or too much loaded with feculence to allow them to pass freely through paper, conical bags made of flannel, felt, tweeled cotton cloth or Canton flannel, linen or calico, and suspended to iron-hooks by rings or tapes, are commonly employed. The first two of the above substances are preferable for saccharine, mucilaginous, and acidulous liquors; the third for oily ones; and the remainder for tinctures, weak alkaline lyes, and similar solutions. These bags have the disadvantage of sucking up a considerable quantity of the fluid poured into them, and are therefore objectionable, except for large quantities, or when they are to be continued in actual use as filters for some time. On the large scale, a number of them are usually worked together, and are generally enclosed in cases to prevent evaporation, and to exclude dirt from the filtered liquor that trickles down their sides. These arrangements will be noticed further on.

A simple mode of filtering aqueous fluids, which are not injured by exposure to the air, is to draw them off from one vessel to another, by means of a number of threads of loosely twisted cotton or worsted, arranged in the form of a syphon. (See engr.) The little cotton rope at once performs the operations of decantation and filtration. This method is often convenient for sucking off the water from a small quantity of a precipitate.

For fuller information on the subject of laboratory filtration, the reader is referred to the following papers (which are too long for quotation here) in ‘The Chemical News’:—

“On a New Mode of Filtration,” by J. B. Cooke, May 30th, 1873; “Filtering Apparatus,” by John F. Kerr, February 6th, 1874; “Implements for Filtration,” by P. Casamajor, July 23rd, 1875, and 30th, 1875; Ibid, by W. Jago, February 4th, 1876; “On Rapid Filtration,” by E. C. H. Hildebrand, August 11th, 1876; also to ‘Journal of the Chemical Society,’ for papers on:—“Simple Suction arrangement for Rapid Filtering,” by C. Holthof, vol. xxxii, part 2, p. 508; “Employment of Compressed Air on Filtering Solutions,” by W. Leübe, vol. xxxii, part 1, p. 270.

When solid substances, as porous stone or earthenware, are used as the media for filtrations, vessels of metal, wood, or stone-ware, are employed to contain them and the supernatant liquid. In these cases the filtering medium is usually arranged as a shelf or diaphragm, and divides the vessel into two compartments; the upper one being intended to contain the dirty liquid, and the under one to receive the same when filtered. Such an apparatus is set in operation by merely filling the upper chamber, and may at any time be readily cleared out by reversing it, and passing clean water through it in an opposite direction. Small arrangements of this kind, intended to be screwed on to the water supply-pipe by either end, and which answer the purpose intended in the most satisfactory manner, have been manufactured and vended under the name of ‘REVERSIBLE’ or ‘SELF-CLEANING FILTERS,’ When pulverulent substances, as sand, coarsely powdered charcoal, &c., are employed, a similar arrangement is followed; but in this case the shelf or diaphragm must consist of any convenient substance pierced with numerous holes, over which must be placed, first a stratum of coarse pebbles, next some of a finer description, and on this a proper quantity of the sand, charcoal, or other medium. Over the whole should be placed another layer of pebbles, or a board or plate of metal or earthenware, pierced with a number of holes, to allow the liquid to be poured into the filter without disturbing its arrangement. Apparatus of this kind, of a permanent description, and arranged for filtering large quantities of liquids, are properly denominated ‘FILTERING MACHINES,’

Among the liquids usually submitted to filtration, the following may be mentioned as the principal—water, oils, syrups, tinctures, vegetable juices, infusions, and decoctions.

The filtration of water may now be considered. The water of our wells is presented by nature ready filtered to the hand of man, and often exhibits an admirable degree of transparency and purity. It acquires this state by percolating through the mineral strata of the earth, which deprives it of the organic matter it derives from the soil and subsoil, but, at the same time, it dissolves a portion of the saline and earthy media through which it passes, and hence acquires that peculiar ‘hardness’ which is constantly found in spring water. On the large scale, this natural system of filtration has been imitated by some of the commercial companies that supply our cities and towns with water. Extensive beds of sand and gravel have been employed, with variable success, as the filtering media; and were it not that filters gradually lose their porosity by the accumulation of the retained matter in their pores, such a method would be excellent. But the great expense of such filters precludes the possibility of frequently cleaning or renewing them, by which means they can alone be kept in an efficient state.

A filter which possesses the advantages of being easily and cheaply cleaned when dirty, and which frees water from mechanical impurities with immense rapidity, may be formed by placing a stratum of sponge between two perforated metallic plates, united by a central screw, and arranged in such a manner as to permit of the sponge being compressed to any required degree. Water, under gentle pressure, flows with such rapidity through the pores of compressed sponge, that it is said that a few square feet of this substance will perfectly filter several millions of gallons of water daily. This method of filtration has been made the subject of a patent, and has been favorably noticed by the legislature.

A few barrels or hogsheads of water may be easily filtered daily, by the arrangement represented in the engraving.

A. A common water-pipe or cock.

b. A false bottom fitting in perfectly water-tight.

c. A perforated wooden or metallic vessel or box covered with a bag of felt or other filtering substance (not shown in the engraving). d. A small tube, fitting water-tight into the false bottom and uniting the interior of the filter with the lower portion of the cask.

It is evident that when water is poured into the upper portion B of a vessel, so arranged, it will sink through the filter c, and pipe d, into the lower chamber C, and this filtration will go on as long as the supply continues, and water is drawn from the cock e. By uniting the cock e with a tank or casks, and by keeping the upper portion B always full by means of a ball-cock, a considerable quantity of water may be thus filtered. The advantage of this plan is, that the filter c can be always readily got at, and easily cleaned or renewed.

For filtering water on the small scale, and for domestic use, ‘alcarazzas,’ diaphragms of porous earthenware and filtering-stone and layers of sand and charcoal, &c., already referred to, are commonly employed as filtering media. The filtering power of porous stone or earthenware may be greatly increased by adopting the arrangement represented in the margin, which consists in making the diaphragm of the shape of a disc (d), supporting plates of the same material, the whole forming but one piece. The ‘PLATYLITHIC WATER-FILTERS,’ which are formed of porous stone cut on this plan, present 200 to 300 square inches of filtering surface. A cheap, useful form of portable filter, is the following, given in the ‘Proceedings of the British Association,’ “Take any common vessel, perforated below, such as a flower-pot, fill the lower portion with coarse pebbles, over which place a layer of finer ones, and on these a layer of clean coarse sand. On the top of this a piece of burnt clay, perforated with small holes, should be put, and on this again a stratum of three or four inches thick, of well burnt pounded animal charcoal. A filter thus formed will last a considerable time, and will be found particularly useful in removing noxious and putrescent substances held in solution by water.” The ‘PORTABLE-FILTERS,’ set up in stone-ware, that are commonly sold in the shops, contain a stratum of sand, or coarsely-powdered charcoal; before, however, having access to this, the water has to pass through a sponge, to remove the coarser portion of the impurities. Among the many new kinds of portable filters now offered for sale, which claim special notice, are the following, viz.—

1. The MOULDED CARBON FILTER, consisting of a spherical or cylindrical vessel formed of compressed carbon.

2. The SILICATED CARBON FILTER, in which the medium is a compact substance, formed of animal charcoal and the ashes of Boghead coal.

Of the many forms of this filter, we may mention the ‘Syphon Filter for Travellers,’ by means of which wholesome water may be drunk from any pond or stream by simply immersing the filter therein and drawing the water through the tube by suction. Of the ‘Silicated Carbon Filter,’ Professor Wanklyn says that it will render river water containing a considerable amount of free and albuminoid ammonia as pure as deep spring water.

3. Bischoff’s Patent Spongy-iron filter.—This differs from one invented many years ago by Dr Medlock, in bringing the water into contact with spongy iron instead of thin iron rods, and thus effecting filtration much more rapidly. Medlock believed that the iron rods brought about the oxidation of the nitrogenous organic matter and its consequent conversion into nitrites and nitrates. Bischoff states that he has experimentally investigated the properties of spongy iron, and finds that it—

a. Decomposes even distilled water, which has been previously boiled.

b. That it reduces nitric acid to ammonia.

c. That the amounts of organic nitrogen and albuminoid ammonia are always much reduced after filtration through spongy iron.

d. That a minute quantity of iron is dissolved by the carbonic acid contained in the water, ferrous bicarbonate being formed. The latter being soon oxidised and precipitated is easily removed by filtration.

e. That the action of spongy iron on impure water is two fold, viz. chemical and mechanical. “The chemical action is clearly indicated by the decomposition of water. The readiest explanation for the decomposition of water, is, the intimate contact between the electro-positive and electro-negative bodies, such as metallic iron and carbon, or even metallic iron and any ferric oxide, which has escaped reduction, or which has been reoxidised by exposure to air or water; and it may well be supposed that, consequent to the galvanic current thus produced, the atmospheric oxygen dissolved in water is ozonised, and caused to act as a powerful oxidising agent in organic matter.”

We extract the tables on the next page from the Sixth Report of the Royal Commission on Rivers’ Pollution. The Commissioners, we may here state, speak in high terms of this filter.

4. The so-called Magnetic carbide of iron filter. In this, the filtering material is said to be prepared by heating hæmatite with sawdust. This filter has a good repute.

⁂ The Royal Commission “on Rivers Pollution” strongly recommend filters of animal charcoal to be recharged every three to six months, “since they found that myriads of minute worms were developed in the animal charcoal, and passed out with the water when these filters were used for Thames water, and when the charcoal was not renewed at sufficiently short intervals.”

Cleansing of Filters.—Every two or three months (according to the kind of water) air should be blown through, and if the charcoal be in the block form it should be brushed. Then four to six ounces of the pharmacopœial solution of potassium permanganate, or twenty to thirty grains of the solid permanganate in a quart of distilled water, and ten drops of strong sulphuric acid, should be poured through, and subsequently a quarter to half an ounce of pure hydrochloric acid in two to four gallons of distilled water. This plan would be useful on foreign stations where the filter cannot be sent home, or taken to pieces; if it can be taken to pieces, the charcoal should be spread out in a thin layer, and exposed for some time to air or sun, or heated in an oven.

The Average Composition of Thames Water, before and after Filtration
through Spongy Iron.

Description. Dissolved Matters.

Total solid impurity. Organic carbon. Organic nitrogen. Ammonia. Nitrogen, as nitrates and nitrites. Total combined nitrogen.

As delivered from Chelsea Waterworks 28·04 ·198 ·042 ·0009 ·117 ·220

The same water filtered through spongy iron 16·8 ·069 ·018 ·019 ·018 ·049

The mean of the 14th and 15th taken after the spongy iron filter had been in operation in the Rivers Commission Laboratory for upwards of eight months. As supplied from Waterworks 24·47 ·170 ·055 ·001 ·098 ·154

After filtration through spongy iron 14·26 ·083 ·016 0 0 ·016

Description. Dissolved Matters.

Previous Sewage or Animal contamination. Chlorine. Hardness. No. of samples analysed.

Temporary. Permanent. Total.

As delivered from Chelsea Waterworks 1·464 2·01 15·5 6·2 21·7 15

The same filtered through spongy iron ·177 2·00 6·8 4·9 11·7 15

The mean of the 14th and 15th samples taken after the spongy iron filters had been in operation in the Rivers Commission Laboratory for upwards of eight months. As supplied from Waterworks ·675 Analysis of the 15th sample. 1·95 — — 19·1 —

After filtration through spongy iron 0 1·95 — — 9·6 —

If sponges are at all used, they should be removed from time to time, and thoroughly washed in hot water.

Oils are filtered, on the small scale, through cotton-wool, or unsized paper, arranged in a funnel; and on the large scale, through long bags, made of tweeled cotton-cloth (Canton flannel). These bags are usually made about 12 or 15 inches in diameter, and from 4 to 8 feet long (see engr.), and are inclosed in bottomless casings, or bags of coarse canvas, about 5 to 6 or 8 inches in diameter, for the purpose of condensing a great extent of filtering surface into the smallest possible space. A number of these double bags (from 1 to 50 or 60) are connected with corresponding holes in the bottom of a block-tin or tinned-copper cistern, into which the oil to be filtered is poured. The mode in which these bags are fastened to the cistern is of the utmost importance, as on the joint being close and secure depends the integrity of the apparatus. Three methods of doing this are figured in the engraving, which, with the references, will explain themselves, the same letters referring to the same parts of each.

Filtering-bag of cotton-cloth.

Cotton filtering-bag, ‘creased,’ or enclosed in its canvas envelope, ready for fixing.

The second of the above arrangements is the least expensive, and certainly the most convenient in practice; and when the cylinder l fits the hole closely (allowing for the bag), is as safe, or safer, than an ordinary screw.

a. Bottom of cistern.

b. Filtering-bag.

c. Screw of the conical nozzle fitting into the cistern.

d. Binding cord connecting bag and nozzle.

e. Binding cord connecting bag and lower nozzle.

f. Bayonet-catch, connecting the lower portion of the nozzle fastened to the bag with the upper and fixed part, g.

i. The thick hem at the top of the bag (purposely made large by enclosing a piece of thick cord therein), resting on the shoulders, k.

l. A metallic cylinder, loosely fitting the hole in the cistern, and over which the top of the bag is drawn, before being put into its place; when fitted, as in the engraving, it retains the hem i securely in its place above the shoulder k.

The bags are surrounded by a wooden screen fitted up with doors for the purpose of keeping off the dust; and the bottom of the apartment is furnished with large steam-pipes, by which a proper temperature may be kept up in cold weather. The use of heat should, however, never be had recourse to when it can be avoided, as although it vastly increases the rate of filtration, the oil so filtered is more apt to become opaque in cold weather than when the process is conducted at the natural temperature of the atmosphere. This is particularly the case with castor oil and sperm oil. In the United States of America, where the latter is consumed in enormous quantities for illumination, the best is always ‘winter strained,’ as it is popularly called. In practice, it is more convenient to have a number of small cisterns at work (say 50 or 100 galls. each), than one or two larger ones, as any accident that may occur is more easily remedied, and that without stopping the whole operation.

When cotton-cloth bags are employed without being ‘creased,’ or enclosed in others of canvas, they should not be longer than about 3 or 4 feet, and not wider than about 5 or 6 inches when filled. When larger they are dangerous.

A convenient method of filtering a single cask of oil is, to insert the pipe of a two-way patent filter into the cork-hole, by which means the whole will be filtered as drawn off, without any trouble on the part of the operator. This filter consists of a porous bag stretched over a perforated metallic vessel, nearly the shape and size of the exterior casing, and its edge is tightly screwed between the sides and bottom of the latter, so as to be quite water-tight. The cock communicates with the interior of the perforated plate and filter, and the supply-pipe with the exterior. By this means the interior chamber, which occupies ⁄6ths of the vessel, rapidly fills with filtered oil, and continues full as long as any liquor remains in the cask. This arrangement is also well adapted to the filtration of wines, beer, cordials, porter, and various other liquors. It is unequalled in simplicity and usefulness. The same filter may be removed from cask to cask, with the facility of a common cock.

The filtration of SYRUPS is now generally effected on the large scale by passing them through the ‘CREASED BAG FILTER’ just described. On the small scale, as employed by confectioners and druggists, they are usually passed through CONICAL FLANNEL BAGS. (See page 726.) The filtration of thick syrups is, however, attended with some difficulty, and it is therefore a good plan to filter them in a somewhat dilute state, and afterwards to reduce them to a proper consistence by evaporation in clean vessels of tinned copper, by steam heat. Syrups, when filtered in a heated state, run well for a time, but the pores of the fabric rapidly get choked, from the thickening of the syrup and partial crystallization of the sugar, occasioned by the evaporation of the aqueous portion from the surface of the bag. This may be partially prevented by enclosing the bag in a metallic casing. On the whole clarification is preferable for syrups to filtration on the small scale. They need only be well beaten up while cold with a little white of egg, and then heated; a scum rises, which must be removed as soon as it becomes consistent, and the skimming continued until the liquid becomes clear. Any floating portions of scum that may have escaped notice are easily removed by running the syrup through a coarse flannel strainer, whilst hot. The most extensive application of the process of filtration in the arts is in the refining of sugars.

Tinctures and dilute spirits are usually filtered, on the small scale, through BIBULOUS or UNSIZED PAPER placed on a funnel; and on the large scale, through thin and fine COTTON BAGS. In general, however, tinctures clarify themselves by the subsidence of the suspended matter, when allowed to repose for a few days. Hence it is the bottoms alone that require filtering; the supernatant clear portion need only be run through a small hair sieve, a piece of tow or cotton placed in the throat of a funnel, or some other coarse medium, to remove any floating substances, as pieces of straw, &c. Spirits which are largely loaded with essential oil, as those of ANISEED, &c., run rapidly through paper or calico, but usually require the addition of a spoonful or two of magnesia before they will flow quite clear. When possible, tinctures, spirits, and all similar volatile fluids, are better and more economically cleared by subsidence or clarification than by filtration, as, in the latter way, a portion is lost by evaporation, and the strength of the liquid is thereby altered.

Vegetable juices should be allowed to deposit their feculous portion before filtration. The supernatant liquid will then be often found quite clear. It is only when this is not the case that filtration should be had recourse to. A small quantity may be filtered through coarse or woollen filtering paper, supported on a piece of coarse calico placed on a funnel; when the quantity is large, one of the CONICAL BAGS before described should be employed. The bottoms from which the clear portion has been decanted should be placed on a separate filter, or else not added until the whole of the other portion has drained through. Vegetable juices are often rendered clear by simply heating them to about 180° or 200° Fahr., by which their albumen is coagulated; they are also frequently clarified by the addition of a little white of egg and heat, in the same way as syrups. Many of them (as those of hemlock, henbane, aconite, &c.) are greatly injured by heat, and must consequently be filtered, or only simply decanted after repose. In all cases they should be exposed to the air as little as possible, as they rapidly suffer decomposition.

Vegetable infusions and decoctions may be cleared by defecation followed by filtration. The conical bags of flannel before described are usually employed for this purpose. When the liquid is to be evaporated to an extract, they are commonly suspended by a hook over the evaporating pan. A convenient method of straining these fluids, practised in the laboratory, is to stretch a square of flannel on a frame or ‘horse,’ securing it at the corners by pieces of string. (See engr.) Such a frame, laid across the mouth of a pan, is more easily fed with fresh liquid than a bag, whose mouth is 40 or 50 inches higher. The same purpose, for small quantities of liquid, is effected by laying the flannel across the mouth of a coarse hair sieve. The concentrated infusions and decoctions being usually weak tinctures, may be filtered in the same way as the latter. (See above.) Many vegetable solutions, that from the viscidity of the suspended matter can scarcely be filtered, may be readily clarified with white of egg in the cold, or pass the filter rapidly if a very small quantity of acetic, tartaric, sulphuric, or other strong acid, is previously added.

Corrosive liquids, as the STRONG ACIDS, are filtered through powdered glass, or SILICEOUS SAND, supported on pebbles in the throat of a glass funnel, or through asbestos or gun-cotton placed in the same manner. Charcoal has also been employed for the same purpose, but is not fit for some acids. Strong caustic alkaline lyes are also filtered through powdered glass or sand. Weak alkaline lyes may be filtered through fine calico, stretched across the mouth of a funnel. Many corrosive liquids, as solution of potassa, &c., require to be excluded from the air during filtration. The simplest apparatus that can be employed for this purpose is that figured in the margin:—(a) is a globular bottle fitted with the ground stopper (d), and having a perforated neck (f) ground to the bottle (b); (c) is a small tube, wrapped round with as much asbestos, linen, or calico, as is required to make it fit the under neck of the bottle through which it passes. The tube (c) may also be fixed by placing pebbles and powdered glass or sand round it, as before mentioned. For use, the solution to be filtered is poured into the bottle (a) nearly as high as the top of the tube (c), and the stopper is replaced. The liquid then descends into (b), and a similar quantity of air passes up the tube into (a). Liquor potassæ may be always obtained fine by depuration in close vessels, when the sediment of lime only need be filtered, which may be effected with calico fixed across the mouth of a funnel.

When a precipitate, or the suspended matter in a liquid, is the object of the filtration, the filter should be of such a nature that the powder may be easily separated from it, when dry, and that with the least loss possible. Linen filters are for this reason preferable for large quantities, and those of smooth bibulous paper for small ones. The powder should be washed down the sides of the filter, and collected, by means of a small stream of water, in one spot at the bottom, assisting the operation with a camel-hair pencil; and, when the whole is dry, it should be swept off the paper or cloth with a similar pencil or brush, and not removed by a knife, as is commonly done, when it can be possibly avoided.

The ‘first runnings’ of liquid from a filter are commonly foul, and are pumped back or returned until the fluid runs perfectly limpid and transparent, when it is ‘turned into’ the ‘filtered liquor cistern,’ or proper receiver. In many cases the liquid does not readily become transparent by simply passing through the filter; hence has arisen the use of FILTERING POWDERS, or substances which rapidly choke up the pores of the media in a sufficient degree to make the fluid pass clear. In the employment of these powders care should be taken that they are not in too fine a state of division, nor used in larger quantities than are absolutely necessary, as they are apt to choke up the filter, and to absorb a large quantity of the liquid. The less filtering powder used, the more rapid will be the progress of the filtration, and the longer will be the period during which the apparatus will continue in effective action. For some liquids these substances are employed for the double purpose of decolouring or whitening, as well as rendering them transparent. In such cases it is preferable first to pass the fluid through a layer of the substance in coarse powder, from which it will ‘run’ but slightly contaminated into the filter; or, if the powder is mixed with the whole body of the liquid, as in bleaching almond oil, &c., to pass the mixture through some coarser medium to remove the cruder portion before allowing it to run into the filter. Another plan is, after long agitation and subsequent repose, to decant the clearer portion from the grosser sediment, and to employ separate filters for the two. Granulated animal charcoal is used according to the first method, to decolour syrups, oils, &c.; and filtering powder by the second and third, to remove a portion of the colour, and to clarify castor and other oils. The common plan of mixing large quantities of filtering powder with castor oil, and throwing the whole into the filter, as adopted by the druggists, is injudicious. When simple filtration is required, it is better to use little or no powder, and to continue returning the oil that ‘runs’ through, until, by the swelling of the fibres of the filter bags, it flows quite clear. By this plan the same filters may be used for a long period of time (for many years), and will continue to work well; whilst, by the usual method, they rapidly decline in power, and soon deliver their contents slowly, and after a short time scarcely at all.

It is often of great advantage to render a filter ‘self-acting,’ or to construct it in such a way that it may ‘feed itself,’ so that it may continue full and at work without the constant attention of the operator. On the small scale, this may be readily effected on the principle of the common fountain lamp (see engr.); and on the large scale, by placing the vessel containing the unfiltered liquid on a higher level than the filter, and by having the end of the supply-pipe fitted with a ball-cock, to keep the liquid in the filter constantly at the same height.

The rapidity of filtration depends upon—the porosity of the filtering medium—the extent of the filtering surface—the relative viscidity or mobility of the filtering liquid—the pressure or force by which the liquid is impelled through the pores of the filter, and—the porosity and fineness of the substances it holds in suspension. The most efficient filter is produced when the first two or the first three are so graduated to the others that liquid filters rapidly, and is at the same time rendered perfectly transparent.

In the common method of filtration no pressure is exerted beyond that of the weight of the column of the liquid resting on the filtering medium, but in some cases additional pressure is employed. This is had recourse to for the purpose of producing a more rapid filtration, and more especially for filtering liquids that, from their viscidity, will scarcely pass through the pores of substances sufficiently fine to remove their impurities in the ordinary way.

One of the easiest means of employing pressure in filtration is to increase the height of the column of the filtering liquid. From the peculiar properties of fluids, by which they transmit pressure in an equal degree in all directions, this column need not be of equal diameter throughout, but may be conveniently contracted to the size of a small pipe, as in the accompanying engraving, which represents a small filter on this construction at work. (a) Is the funnel or reservoir of foul liquid; (b) a small pipe conveying the liquid to the filter; (c c) a chamber, of which the upper portion (d) is filled with the descending liquid, and the lower portion (e) with the filtering media; (i i) are screws by which the bottom plate is fastened on, which plate is removed to clean out or renew the filter. For use, the cocks (k) and (l) are closed, and the liquid poured into the funnel (a); the cock (k) is next opened, and, in a few minutes after, the cock (l), when an uninterrupted flow of filtered liquor will be obtained as long as any fluid remains in the funnel (a) and the tube (b). The length of the tube determines the degree of pressure. Care must be taken first to pass the foul liquid through a hair sieve, or some other strainer, to remove any substance that might choke up the pipe (b).

Another method of employing pressure in filtration is the withdrawal of the air from the receiving vessel, as in the vacuum filter, by which a pressure of about 14⁄2 lbs. to the square inch becomes exerted on the surface of the liquid by the atmosphere. The vacuum in the receiving vessel may be produced by the air-pump, by steam, or by the Bunsen or Sprengel pump.

A commoner method of applying pressure than either of those already mentioned is to condense the air over the surface of the liquid by means of a forcing-pump, or by steam.

On the small scale, pressure may be applied to filtration by means of a syphon, whose shorter leg has its mouth blown into the shape of a bell or funnel, over which filtering paper or fine calico may be stretched.

The application of pressure to filtration is not always advantageous, and beyond a certain limit is generally attended with inconvenience, if not with absolute disadvantage. It is found in practice that fluids under pressure take a longer period to run clear than without pressure, and that ruptures of the media more frequently take place in the former case, or with pressure, than in the latter. Great pressure is in no case advantageous.

The filters already noticed are those that act by the fluid descending through the media; but in some cases the reverse method is employed, and the liquid filters upwards, instead of downwards. These are called ascending filters, and are often preferable to those on the descending principle, because the suspended matters that require removal by filtration usually sink, and thus a portion escapes being forced into the pores of the filter. They are also more convenient when pressure is employed. The construction depends upon the same principles as the common filter, and merely requires that the feeding vessel should be higher than the upper surface of the filtering media. Oils are conveniently filtered in this way, because of their little specific gravity. By fixing a small filter on this principle into the head of a cask, and pouring in water through a funnel, whose neck reaches nearly to the bottom of the cask, the oil will float up and pass the filter, leaving the sediment behind. In cold weather hot water may be employed.

a. Cask of oil.

b. Stand.

c. Funnel for water.

d. Filter.

In some cases the upward and downward systems of filtration are united in the same apparatus, and this plan is advantageous where the space for operating is limited. For this purpose it is merely necessary to connect the bottom of an ascending filter with the top of a descending one, or the reverse; the proper pressure being in either case applied.

Filtration, the Laws of. The ‘Revue Universelle des Mines,’ 1874, pp. 469, 551 contains a paper by M. Paul Havre recording his investigations on the rapidity of the filtration of water through sand, wool, &c., which resulted in ascertaining and measuring the influences which may modify the flow of water. In all cases of filtration, the influences which are exerted are:—the pressure and temperature of the water, the thickness of the filtering medium, compression in the case of fibrous filters, the size of the grains and their mixture in the case of a filtering medium analogous to sand. The influence of obstruction, due to the dirtiness of the filter, depends on circumstances too variable to be taken into account. The delivery of a filter per square mètre per 24 hours is equal to two cubic mètres multiplied by the pressure of water in mètres, divided by the thickness of the filtering medium in mètres. An application of this formula is made to existing filter beds, including those at Southwark and at the Chelsea waterworks.

The first experiments for ascertaining the influence of a head of water on the delivery led to the following results:—The delivery increases in a higher ratio than the square root of the pressure, due to the height (Torrecelli’s Law); the delivery increases in direct ratio to the height of the column of water above the filter, admitting a previous initial delivery, due solely to the pressure of water above the filter; the co-efficient of the increase of delivery is constant, and in this case of a filtering substance 8·662 inches (22 centimètres) thick, is equal to 0·106 pint (6 centilitres) for sand to 0·528 pint (30 centilitres) for compressed wool, and to 0·792 pints (45 centilitres) for wool only slightly compressed.

The subsequent experiments were made with graduated transparent cylinders, 3·28 feet (1 mètre) high, with the ends perfectly level, the filtering substances being kept in place by a thick double cloth tied tightly under the bottom of the tube. This apparatus presented no other obstacle to the running of the water than the layer of filtering substance; it permitted experiments to be made at all temperatures, and the thickness of the filtering medium to be measured exactly.

In these experiments sand is ‘taken as the type of pulverulent substances,’ but an unexpected difficulty was encountered in the settling or partial agglomeration of the large and small grains of the unsifted sand, thus diminishing the delivery of water to one half, one third, and ultimately to one fifth of its previous volume. This led to the adoption of sand—the grains of which were uniform in size, and to the discovery of the fact that, other tissues being equal, the resistance of filtration is constant when the sand is coarse, when the grains of fine sand are of nearly equal size, and when there is but little fine sand mixed with the coarse. From experiments in filtering through a layer of coarse sand approximately 4 inches (10 centimètres) thick, it was found that the higher the temperature the more rapid was the delivery, and by filtering through a layer of coarser sand 11·8 inches (30 centimètres) thick, the conclusion was arrived at that the temperature exerts an influence in proportion to the thickness of the layer.

See Air-Pump, Bunsen’s Water-Air Pump; Clarification; Defecation; Finings, &c.

FI′NINGS. Substances used by publicans, brewers, wine merchants, &c., to clarify their liquors.

Prep. 1. (Brewer’s finings; Cooper’s f.) Isinglass (finely shredded), 1 lb., and sour beer or cider or vinegar, 3 or 4 pints, are macerated together, and more of the sour liquor added as the isinglass swells, until about a gallon has been used, agitation with a whisk or a small bundle of twigs being occasionally had recourse to, for the purpose of promoting the solution. As soon as the whole of the isinglass is dissolved, the mixture is reduced to the consistence of thin syrup, with weak mild beer, or cider, or any other liquid that the finings are intended for. The whole is next strained through a tammy cloth or a hair sieve, and at once reduced to a proper state of dilution, by the addition of more liquor. Product, 6⁄2 to 7 galls. “A pound of good isinglass will make about 12 galls. of finings.” (Ure.) Used to clarify fermented liquors, especially beer. 1 to 1⁄2 pint is the usual dose for a barrel of ale or porter; and a quart for a hogshead of cider or wine.

2. (Spirit finings.)—a. Alum (ord. cryst.), 1 lb.; powder, and divide it into 12 equal portions, which are to be separately wrapped in blue paper, and marked No. 1. Next take of carbonate of soda (sesquicarbonate of the shops), 6 oz.; divide this as the last, wrap it in white paper, and mark each parcel No. 2. Keeps dry anywhere.

b. From alum, 1 lb.; salt of tartar (dry), ⁄4 lb.; proceed as before. The white papers containing the salt of tartar must be kept in a dry, well-corked, wide-mouthed bottle or jar. Both of the last two are used to clarify gin and cordials. The contents of one of the blue papers are dissolved in about a pint of hot water, and the resulting solution is well ‘rummaged up’ with the liquor. A solution of the contents of one of the white papers, in about ⁄2 pint of hot water, is then added, and the agitation continued for some minutes longer; after which the cask is ‘bunged’ close and the whole allowed to repose until the next day. This is sufficient for a barrel (say 30 to 36 galls.), but many persons use double the quantity. The effect is not only to clarify, but also to ‘blanch’ the liquor.

Obs. Good liquors, either fermented or spirituous, need no artificial ‘fining,’ as they always clarify themselves by repose. With those, however, which are out of ‘condition,’ or of inferior quality, it is often necessary, as, without such a proceeding, they remain unsaleable. This is particularly the case with malt liquor. “Attempts to clarify it in the cask seldom fail to do harm. The only thing that can be used with advantage for fining foul or muddy beer is isinglass.” (Ure.) The disadvantages resulting from the artificial clarification of fermented liquors are—that they do not afterwards ‘stand well on draught,’ that much of the conservative astringent matter which they contain is precipitated with the ‘finings,’ that their piquancy and flavour is more or less diminished, and that they are more than usually liable to become flat and vapid, whether in cask or bottle. The larger the proportion of ‘finings’ used, the more marked are their injurious effects, and the shorter the interval which elapses before the accession of the several symptoms referred to. We have seen the most disastrous consequences follow the injudicious use of ‘finings,’ more especially in respect to those liquors in which a certain amount of piquancy, astringency, and briskness, is an essential condition. In one instance which came under our notice upwards of 30 barrels of ‘underground’ (a very strong old ale) was thus reduced in value to less than 1-3rd its original cost; and in another, a large bottled stock of the ‘finest old Burton’ was found to be utterly unsaleable. In both cases the ‘spoiled liquor’ was got rid of by mixing it in and selling it with 3d. and 4d. beer.

Liquors which ‘refuse to fine’ or become clear, when treated with ‘finings’ in the usual manner, are called ‘stubborn’ by coopers and cellarmen. See Brewing, Gin, Malt, Liquors, Wines, &c.

FIRE. The calamities resulting from this destructive agent are of such frequent occurrence, as to justly claim a notice of the subject here. The causes of fires are numerous, and of a varied character, and, in most instances, difficult to determine, because it is the interest of those concerned to suppress all evidence connected with the matter. Accident, that convenient word given to the imaginary hack to which so many fires are referred, if truthfully interpreted, will, in general, be found to be equivalent to carelessness, recklessness, or guilt. We believe that there are few fires which have happened that might not have been prevented by the exercise of common prudence, and that a vast number have been caused by direct negligence, arising from sheer laziness and indifference, to use no harsher terms. As familiar instances, may be mentioned—allowing sparks to fall on the ground and remain there without extinguishing them; carrying a naked candle into rooms containing inflammable substances; smoking carelessly and in dangerous places, as workshops, warehouses, on shipboard, &c.; keeping instantaneous light matches in improper places, and neglecting to pick up those that may happen to fall on the ground, &c. &c. The list might easily be extended, but we believe every reflecting reader can do so for himself. The great increase in the number of fires since the introduction of lucifer matches, and the almost general use of tobacco, cannot fail to have attracted the attention of every one. The danger of matches falling about might be avoided by the use of those which can only be ignited by rubbing them on the prepared surface of the box. These ‘safety matches’ are coming into general use, and must eventually supersede all the more dangerous kinds.

The late Mr Braidwood classes the causes of fires under the following heads:—1. Inattention in the use of fires and lights. 2. Improper construction of buildings, &c. 3. Furnaces or close fires, for heating buildings, or for mechanical purposes. 4. Spontaneous ignition. 5. Incendiarism.

Amongst many other causes of fire, too numerous to specify, may be noticed—incautiously approaching window- and bed-curtains with a candle or lamp, airing linen before the fire, allowing children to play with fire, women’s dresses taking fire, and taking off the burning coals from a fire and laying them on the hearth. Another very common cause of fire is covering up a fire-place when not in use with wood, or paper and canvas, &c. The soot falls either from the flue itself or an adjoining one into the grate; a neighbouring chimney takes fire, a spark from this falls down the blocked-up flue, ignites the soot in the grate, which smoulders until the covering is burnt through, and thus sets the building on fire.

Another cause of fire, and one which cannot be too strongly condemned, is the dangerous practice of reading in bed by candle-light. A very serious annual loss of property is also caused by want of proper care in hanging up or removing the goods in linendrapers’ shop windows when the gas is burning. Another frequent cause of fire is the employment of young children in lighting fires, from their propensity to play with flame.

The employment of close fires with brick flues is also a frequent source of danger. Frequently, from various causes, the furnace almost always cracks, thus giving egress to smoke and flame. When this occurs no time should be lost in thoroughly repairing the defect, or building a new furnace; merely plastering over the surface will be found an ineffective and dangerous remedy.

To guard against the dangers arising from the ignition of wearing apparel many methods have been suggested for rendering fabrics flame proof, all of them consisting in soaking the dress in a weak solution of a non-inflammable substance, such as chloride of zinc, alum, tungstate of sodium, sulphate of ammonia, &c. Of these alum has the advantage of greatly improving the appearance of the fabrics, especially if they be coloured.

Fire-guards, particularly where there are children, ought to be adopted much more generally than they appear to be.

Prev. This consists of the exercise of those ordinary precautions which the good sense of every careful and trustworthy man, be he taskmaster or servant, cannot fail to suggest. It would be useless to enumerate them.

Immediately on the fire being discovered, secure an alarm being given to the nearest of the fire escape stations, not delaying an instant; do not wait “to see if it is wanted.” Life is more valuable than property, and events have often proved how fatal even a moment’s hesitation is in sending for the fire-escape.

The late Mr Braidwood’s advice was, “that if the fire appears at all serious, and there are fire-engines within a reasonable distance, that it is best to wait until they arrive; many buildings have been destroyed from opening doors, and trying to extinguish fires with insufficient means. If no engines are within reach it is advisable to keep a hand-pump. If that is not to be had, the next best thing is to collect as many buckets outside the room on fire as can be obtained, keeping the door shut; then to creep into the room on hands and knees (if the heat and smoke are considerable), and throw the water as nearly in the direction of the fire as possible, keeping the door shut while more water is being collected.

“The police of the metropolis understand shutting up fires so well, that they have in many instances kept fires two or three miles distant from the engine-stations, shut up till the fireman arrived in time to extinguish them.”

Fires might often be readily extinguished when first discovered by the timely application of a few buckets of water. When an apartment is found to be on fire, the door, chimney, and windows should be immediately closed, if possible, and only opened for the purpose of projecting water on the flames. By this means the supply of air will be cut off, and rapid combustion prevented. The same applies to the lower doors and windows of a house (especially the shop window), which are often injudiciously kept open or removed, under the pretence of rendering assistance. The neglect of this precaution has often caused a mere smouldering fire, that might have been easily put out, to burst into an unextinguishable mass of flame.

It has been proposed at various times to make certain additions to the water used for the purpose of extinguishing fires, in order to render its action more certain and effective. It is found that sal ammoniac (5 oz. to the gall.) exerts this property in a remarkable degree. Several other articles, as common salt, pearlash, and kitchen soda, act in the same way, though less effectively. A few buckets of such water will speedily arrest the progress of a fire before it has much extended itself. Such a plan is easily applied, by adding the saline matter to the buckets of water, which are either used by hand, or to feed the engine for the first few minutes of its working. When, however, a fire has made much progress, the action of such substances becomes scarcely perceptible.

Chimneys on fire are readily extinguished in several ways, without having recourse to throwing water down them from the top, by which much damage is frequently done to the furniture in the rooms. One of the simplest methods is, to cautiously scatter a handful of flowers of sulphur over the dullest part of the burning coals; the sulphurous vapours, being incapable of supporting combustion, rapidly extinguish the flames. Another method is, to shut the doors and windows, and to stop up the bottom of the chimney with a piece of wet carpet or blanket, throwing a little water or flowers of sulphur, or even common salt, on the fire immediately before doing so. By this means the draught is stopped, and the burning soot extinguished for want of air. In many of the first-class houses recently erected, ‘fire-place shutters’ are provided, which, when partly drawn down, act as powerful bellows or ‘blowers’ and which, when wholly drawn down, so as to touch the hearth-stone, entirely close up the fireplace, and instantly extinguish the combustion of the fuel in the grate, or that of the soot in the chimney. This simple arrangement, the advantages of which were pointed out in an early edition of this work, renders fires in chimneys of little moment, as it is only necessary to draw down the shutter to put them out. If a chimney is stopped at top, instead of at the bottom, the whole of the smoke must, of necessity, be driven into the apartment.

In France, M. Marateuh has successfully applied the principle of Davy’s safety lamp for the prevention of fires in chimneys. He places fire-frames of iron work near the base of the chimney, one above the other, about one foot apart; no flame passes through them, whilst the draught in the chimney is not interfered with, the result being that no fire can happen in the chimney.

Escape from apartments on fire may be best effected by creeping on the hands and knees. In this way the window or door may be reached. It is found that the atmosphere of a room so full of smoke as to produce suffocation to a person standing upright, may generally be safely breathed on nearly a level with the floor. A damp cloth, or handkerchief, tied over the mouth and nostrils, or, still better, over the whole face and head, will enable a person to effect a passage through the densest smoke, and, in many cases, to escape from buildings on fire, when otherwise it would be impracticable. Should descent by the staircase be found impossible, then the window should be immediately sought, and a ladder or fire-escape waited for. In the absence of either, if the danger is imminent, a rope should be made by tying the sheets and blankets of the bed together, one end of which should be firmly secured to a chair or table, or preferably to one of the bed-posts, and with this apparatus descent should be cautiously attempted. Jumping out of the window should be avoided, as persons who have not been brought up as clowns, or harlequins, run just as much danger in performing such an exploit as they do by remaining in the burning building. When it is impossible to escape from a burning building by the stairs or windows, retreat may be sometimes secured by a trap door opening on to the roof, or by a skylight, when, unless it be an isolated house, the roof of one of the adjoining buildings may probably be gained with safety.

Fire-escapes of various kinds have been employed of late years in the metropolis, and have proved of the greatest value in rescuing persons from burning buildings.

It is said that there is no instance on record of a person being burnt to death in a dwelling-house in Edinburgh, where the houses are usually high; yet in London, where fire-engines and fire-escapes are provided in greater numbers, deaths are very frequent from this cause. The reason of this difference is, that in the former city the stairs are all made of stone, by which means a road of escape is secured.

The clothes of females and children, when on fire, may be most readily extinguished by rolling the sufferer in the carpet, hearth-rug, table-cover, a great-coat, cloak, or any other woollen article at hand. If this be expertly done, the flames may be rapidly put out, unless the skirts of the dress be distended by hoops or crinoline, when there is great difficulty in staying the progress of the flames. Should assistance not be at hand, the person whose clothes are on fire should throw herself on the ground, and roll the carpet round her, as before described; or if such a thing is not in the room, she should endeavour to extinguish the flames with her hands, and by rapidly rolling over and over on the floor. In this way the fire will be stifled, or at least the combustion will proceed so slowly that less personal injury will be experienced before assistance arrives. The advantage of assuming the horizontal position is manifest from the fact that nine times out of ten it is the lower parts of the dresses of females that first catch fire.

The extinction of fires on board ships by means of carbonic-acid gas was some years since suggested to the Admiralty by Mr J. R. Hancorn. He proposes that a simple and economical apparatus should be attached to every decked vessel capable of supplying this gas, which is a well-known non-supporter of combustion, and will extinguish fire at the very instant of coming in contact with the burning matter. Chalk with sulphuric acid diluted with water (vinegar with any other acid will do) yields 44% of the gas; hence, a ton of chalk, and a fourth part of that quantity of sulphuric acid, will be found sufficient to extinguish any fire on board a ship. Mr Hancorn also proposed this as a method of destroying vermin in ships, such as rats and cockroaches, for which purpose it is more easily applied and more effectual than that usually adopted. This plan was rejected by the Admiralty, from a fear that the destructive action of the gas might extend to the crew as well as the fire. But “it surely is possible by mechanical means to expel the gas before again entering the ship’s hold. At any rate, the grand point would be obtained of extinguishing the fire, though the crew might have only the deck to stand on.”

Precautions to be taken against a Fire amongst Farming Stock.—The following are the suggestions of Mr Beaumont, the secretary of the County Fire Office:—

“Forbid your men to use lucifer matches, to smoke or light pipes or cigars, destroy wasp nests, or fire off guns in or near the rickyard, or to throw hot cinders into or against any wooden out-building on the farm, on pain of instant dismissal.

“Place your ricks in a single line, and as far distant from each other as you conveniently can. Place hayricks and cornstacks alternately; the hayrick will check the progress of the fire. Keep the rickyard, and especially the spaces between the stacks and ricks, clear of all loose straw, and in all respects in a neat and clean state. The loose straw is more frequently the means of firing than the stack itself. Have a pond close to the rickyard, although there may be a bad supply of water. When a steam thrashing machine is to be used, place it on the lee-side of the stack or barn, so that the wind may blow the sparks away from the stacks. Let the engine be placed as far from the machine as the length of the strap will allow. Have the loose straw continually cleared away from the engine; see that two or three pails of water are kept close to the ashpan, and that the pan itself is kept constantly full of water.”

It is often difficult to get horses out of buildings on fire, but it is said that they will readily come out if, after being blindfolded, the saddle and bridle, or the harness, &c., to which they are accustomed, are thrown over them as usual.

We learn from the last report issued by Captain Shaw that the actual number of fires in the year 1877 in London was 1533. Of these fires 1374, or 90 per cent., were slight, no persons being endangered, and no considerable destruction of property taking place. The number of really serious conflagrations was 150; in 88 of these life was endangered, and in 24 cases there was loss of life. The actual number of persons whose lives were in danger was 165; but of these 136 were saved, and the lives eventually lost amounted only to 29. The smallness of the loss is due in great degree to the courage of the members of the Brigade, seven of whom have been commended for special efforts for saving life during the year. Even of the twenty-nine persons who perished fourteen were taken alive out of the burning buildings, and died in hospital of their wounds. It is very satisfactory in view of the vast height of buildings used in business, and the flimsy character of so many London houses, that the risk of death from fire should be so small. It is one of the very slightest risks to which we are exposed in modern London. The fire-escapes must of course be credited with much of this security. There are now 108 stations of these useful machines; and instances of their utility in rescuing the inmates of burning houses are constantly occurring.

The various tables which Captain Shaw appends to his report give some very curious details as to the character of London fires. The hours at which they most commonly break out are by no means those which are popularly supposed to be the most dangerous. No considerable proportion occur after people have gone to bed. From seven o’clock in the evening till eleven o’clock there are more alarms of fire than in an equal portion of the twenty-four hours. Not a third of the number which occur in these evening hours take place in the small hours of the morning, which are in fact less destructive than the same period in the afternoon. There are, moreover, in the detailed list of fires some curious statistics, illustrating the comparative security of private houses over places of business. A very large part of the half million houses in London must come under the description of private dwellings, yet the alarms of fire in this class of buildings were only 316 in the year, and only in five of those were there serious conflagrations. In the lists of business premises nearly every trade in the metropolis is mentioned; and next to houses let out in lodgings, public-houses seem to suffer most. The causes of fires tell the old story of carelessness. They were instances of the almost inconceivable folly of seeking for an escape of gas with a lighted candle. The throwing down of lights is responsible for a considerable number of fires. Ordinary cases of chimneys on fire are not included in Captain Shaw’s summary; but they give the brigade a good deal of work. The number of calls of this kind was 3744, of which 1256 proved to be false alarms. The number of these false alarms will probably be reduced when the stations at which men with hose are situated are more numerous.

Fire Anni′hilator (Phillips’s). This is essentially a gaseous fire engine, which at any moment can be made to discharge a stream of mixed gases and vapours having the power of checking combustion. When first introduced it was generally regarded as a most important invention, but it has not proved an effective substitute for the common water engine. For extinguishing fires on board ship and in close apartments it is undoubtedly well adapted, but as a street engine it is comparatively useless, owing to the unmanageable nature of its fire-annihilating vapours.

The composition with which the ‘Fire Annihilator’ is charged is a mixture of dried ferrocyanide of potassium, sugar, and chlorate of potassa. It is set in action by a blow on a glass vessel containing oil of vitriol, which, being fractured, permits the acid to flow over the ‘charge,’ when the anti-combustion gas is liberated, and rushes forth with great impetuosity.

Fire-damp. See Hydrogen (Light Carburetted).

Fire-engine. The common fire-engine is a compound forcing-pump, consisting of two ‘forcing-pumps’ placed on opposite sides of an ‘air-vessel,’ with which both communicate. The ‘fulcrum’ of the ‘lever’ by which both pumps are worked is placed midway between them; consequently they act alternately in charging the air-vessel. In order to obtain a very forcible jet it is necessary to prevent the escape of any portion of the contents of the air-vessel until the confined air is considerably compressed. The lever is connected with handrails on each side of the engine, and these are alternately raised and depressed by the workers. Engines worked by steam power are now common in London and most of our large towns.

Fire-Extinguishing Powder (Feuerloschpulver), Bucher Leipzig. Nitre, 59 parts; sulphur, 36 parts; coal, 4 parts; iron oxide, 1 part. (Wittstein.)

Fire, how to light a. In a close stove the first thing is to empty the fireplace. Take out the larger cinders and half-burnt coal with your fingers, and lay them on one side for lighting the fire; then rake out all the ashes (this can be done with the lids on, then it will not make so much dust). Next take off all the lids, and sweep all the soot carefully out; once or twice a week the flue pipe must be taken off and cleared out, also the flues under the oven. The soot should be carried away at once, as it blows about. Then blacklead the stove; put in a few cinders, lay on them a piece of paper and a few sticks crossing each other; on these lay very lightly some pieces of half-burnt coal and a few cinders, leaving space for the draught.

Do not fill the grate full; put the lids on, draw out the damper, light the fire, and shut the front door. An open fire is lighted in much the same way. There are no flues to clean out; but the chimney, as high as one can reach and behind the register door, should be cleared from soot daily.

Fire-proofing. See Incombustibility, &c.

Fireworks. See Pyrotechny, and below.

FIRES. (In pyrotechny.) Coloured fires may be termed, not inaptly, the chefs-d’œuvre of the pyrotechnist’s art, since on their excellence the attractions of most other varieties of fireworks depend. The following forms, under judicious management, yield fires of remarkable beauty.

Blue Fire. Prep. 1. From metallic antimony, 1 part; sulphur, 2 parts; nitre, 5 parts.

2. From realgar, 2 parts; charcoal, 3 parts; chlorate of potassa, 5 parts; sulphur, 13 parts; nitrate of baryta, 77 parts.

3. (Mr A. Bird.) Charcoal and orpiment, of each 1 part; black sulphuret of antimony, 16 parts; nitre, 48 parts; sulphur, 64 parts.

4. (Fownes.) Tersulphuret of antimony, a part; sulphur, 2 parts; dry nitre, 6 parts. This is the composition used for the Bengal or blue signal light employed at sea.

5. (Prof. Marchand.) Sulphur, sulphate of potassa, and ammonio-sulphate of copper, of each 15 parts; nitre, 27 parts; chlorate of potassa, 28 parts. For theatrical illuminations. This may be rendered either lighter or darker coloured by lessening or increasing the quantities of the sulphate of potassa and ammonio-sulphate of copper.

6. (Light blue—Marchand.) Sulphur, 16 parts; calcined alum, 23 parts; chlorate of potassa, 61 parts.

7. (Dark blue—Marchand.) Calcined alum and carbonate of copper, of each 12 parts; sulphur, 16 parts; chlorate of potassa, 60 parts.

8. (Marsh.) Sulphate of copper, 7 parts; sulphur, 24 parts; chlorate of potassa, 69 parts.

9. (Ruggieri.) Nitre, 2 parts; sulphur and zinc, of each 3 parts; gunpowder, 4 parts.

10. From sulphur, 1 part; dried verdigris, 2 parts; chlorate of potassa, 9 parts.

Fire, Crimson. Prep. 1. (Marsh.) Chlorate of potassa, 4⁄4 parts; charcoal (alder or willow), 5⁄4 parts; sulphur, 22⁄2 parts; nitrate of strontia, 67⁄2 parts. For pots.

2. (Marsh.) Charcoal, 4⁄4 parts; sulphuret of antimony, 5⁄2 parts; chlorate of potassa, 17⁄4 parts; sulphur, 18 parts; nitrate of strontia, 55 parts. For boxes and stars.

3. (Marchand.) Sulphur, 16 parts; chalk (dry), 23 parts; chlorate of potassa, 61 parts. Turns on the purple. See Red Fire (below).

Fire, Green. Prep. 1. Nitrate of baryta, 77 parts; chlorate of potassa, 8 parts; fine charcoal, 3 parts; sulphur, 13 parts.

2. From metallic arsenic, 2 parts; charcoal, 3 parts; chlorate of potassa, 5 parts; sulphur, 13 parts; nitrate of baryta, 77 parts. Very beautiful, particularly when burnt before a reflector.

3. (Mr A. Bird.) Charcoal and black sulphuret of antimony, of each 2 parts; chlorate of potassa, 5 parts; sulphur, 6 parts; nitrate of baryta, 80 parts.

4. (Fownes.) Lampblack, 1 part; chlorate of potassa, 4 parts; sulphur, 6 parts; dry nitrate of baryta, 18 parts.

5. (Marchand.) Boracic acid, 10 parts; sulphur, 17 parts; chlorate of potassa, 73 parts. Very beautiful.

6. (Marchand.) Chlorate of potassa, 18 parts; sulphur, 22 parts; nitrate of baryta, 60 parts. For theatrical illuminations.

7. (Light green—Marchand.) Sulphur, 16 parts; carbonate of baryta, 24 parts; chlorate of potassa, 60 parts. Extremely delicate.

8. (Marsh.) Charcoal and sulphuret of arsenic, of each 1⁄4 parts; sulphur, 10⁄2 parts; chlorate of potassa, 23⁄4 parts; nitrate of baryta, 62⁄2 parts. For pots or stars.

Fire, Lilac. Prep. 1. (Marsh.) Black oxide of copper, 6 parts; dry chalk, 20 parts; sulphur, 25 parts; chlorate of potassa, 49 parts. For pans.

2. (Marsh.) From black oxide of copper, 3 parts; dried chalk, 22 parts; sulphur, 25 parts; chlorate of potassa, 50 parts. For stars.

Fire, Orange. See Red Fire, No. 8 (below).

Fire, Pink. Prep. (Marchand.) Charcoal, 1 part; chalk and sulphur, of each 20 parts; chlorate of potassa, 27 parts; nitre, 32 parts. For theatrical illuminations. See Red Fire, No. 10 (below).

Fire, Purple. Prep. 1. From lampblack, realgar, and nitre, of each 1 part; sulphur, 2 parts; chlorate of potassa, 5 parts; fused nitrate of strontia, 16 parts.

2. (Marsh.) Sulphuret of antimony, 2⁄4 parts; black oxide of copper, 10 parts; sulphur and nitrate of potassa, of each 22⁄4 parts; chlorate of potassa, 42 parts. For pans.

3. (Marsh.) Sulphate of copper, 9⁄4 parts; sulphur, 13 parts; chlorate of potassa, 77⁄4 parts. For stars.

4. From sulphur, 12 parts; black oxide of copper, 12 parts; chlorate of potassa, 30 parts. See Crimson Fire, No. 3 (above), and Red Fire, No. 9 (below).

Fire, Red. Prep. 1. From sulphur, sulphuret of antimony, and nitre, of each 1 part; dried nitrate of strontia, 5 parts.

2. (Mr A. Bird.) Charcoal, 1 part; black sulphuret of antimony, 4 parts; chlorate of potassa, 5 parts; sulphur, 13 parts; dried nitrate of strontia, 40 parts.

3. (Fownes.) Lampblack, 2 parts; chlorate of potassa, 8 parts; sulphur, 9 parts; dried nitrate of strontia, 32 parts.

4. (Marchand.) Sulphur, 16 parts; carbonate of strontia, 23 parts; chlorate of potassa, 61 parts.

5. (Marchand.) Chlorate of potassa, 20 parts; sulphur, 24 parts; nitrate of strontia, 56 parts. For theatrical illuminations.

6. (Marsh.) Coaldust, 2 parts; gunpowder, 6 parts; sulphur, 20 parts; dried nitrate of strontia, 72 parts.

7. (Ruggieri.) Sulphuret of antimony, 4 parts; chlorate of potassa, 5 parts; sulphur, 13 parts; fused nitrate of strontia, 40 parts. A little charcoal or lampblack makes it burn quicker.

8. (Orange red—Marchand.) Sulphur, 14 parts; chalk, 34 parts; chlorate of potassa, 52 parts.

9. (Purple red—Marchand.) Sulphur, 16 parts; chalk, 23 parts; chloride of potassa, 61 parts.

10. (Rose-red—Marchand.) Sulphur, 16 parts; dried chloride of calcium, 23 parts; chlorate of potassa, 61 parts. See Pink Fire.

11. From charcoal, 2 parts; chlorate of potassa, 6 parts; sulphur, 13 parts; dried nitrate of strontia, 40 parts.

Fire, Violet. Prep. 1. From charcoal, 8 parts; sulphur, 10 parts; metallic copper, 15 parts; chlorate of potassa, 30 parts.

2. (Dark violet—Marchand.) Alum and carbonate of potassa, of each 12 parts; sulphur, 16 parts; chlorate of potassa, 60 parts.

3. (Pale violet—Marchand.) Sulphur, 14 parts; alum and carbonate of potassa, 16 parts; chlorate of potassa, 54 parts.

Fire, White. Prep. 1. From nitre, 60 parts; sulphur, 20 parts; black antimony, 10 parts; meal powder, 6 parts; powdered camphor, 4 parts. For either pans or stars.

2. (Mr A. Bird.) White arsenic, 1 part; charcoal, 2 parts; black antimony, 16 parts; nitre, 48 parts; sulphur, 64 parts.

3. (Marchand.) Charcoal, 2 parts; sulphur, 22 parts; nitre, 76 parts. For theatrical illuminations.

4. (Marchand.) Gunpowder, 15 parts; sulphur, 21 parts; nitre, 64 parts. As the last.

5. (Marsh.) Gunpowder, 12⁄2 parts; zinc filings, 18 parts; sulphur, 23 parts; nitre, 46⁄2 parts. For pans.

6. (Marsh.) Zinc dust or filings, 15 parts; sulphur, 28 parts; nitre, 57 parts. For stars.

7. (Ruggieri.) Sulphur, 13⁄4 parts; sulphuret of antimony, 17⁄4 parts; nitre, 48 parts.

8. (Ruggieri.) From realgar, 2 parts; sulphur, 7 parts; nitre, 24 parts.

9. (Ruggieri.) Charcoal, 1 part; sulphur, 24 parts; nitre, 75 parts.

10. (Ruggieri.) Iron or zinc borings, 25 parts; gunpowder, 100 parts.

Fire, Yellow. Prep. 1. From sulphur, 16 parts; dried carbonate of soda, 23 parts; chlorate of potassa, 61 parts.

2. (Marchand.) Gunpowder, 14 parts; sulphur, 16 parts; dried soda, 20 parts; nitre, 50 parts.

3. (Marchand.) Charcoal, 1⁄2 parts; sulphur, 17⁄2 parts; dried soda, 20 parts; nitre, 61 parts.

Green-coloured Fires.

No. Potassium Chlorate,
per cent. Barium Nitrate,
per cent. Sulphur,
per cent.

1 36 40 24

2 29 48 23

3 24 53 23

4 21 57 22

5 18 60 22

6 16 62 22

7 14 64 22

8 13 66 21

9 12 67 21

10 11 68 21

11 10 69 21

12 9·5 69·5 21

13 9 70 21

14 8·5 70·5 21

15 8 71 21

Red-coloured Fires.

No. Potassium Chlorate,
per cent. Strontium Nitrate,
per cent. Sulphur,
per cent. Carbon Powder,
per cent.

1 40 39 18 3

2 32 46 19 2

3 27 51 20 2

4 23 55 20 2

5 20 58 20·5 1·5

6 18 60 21 1

7 16 61·6 21·2 1·2

8 15 63 21 1

9 13 64 22 1

10 12 65 22 1

11 11 66 22 1

12 10 67 22 1

13 10 67·25 22 0·75

14 9·25 68 22 0·75

15 9 68·35 22 0·65

Violet-coloured Fires.

No. Potassium Chlorate, per cent. Calcium Carbonate, per cent. Malachite powdered, per cent. Sulphur, per cent.

1 52 29 4 15

2 52 28 5 15

3 52 26 7 15

4 52 24 9 15

5 52 23 10 15

6 52 21 13 15

7 51 20 14 15

8 51 18 16 15

9 51 16 18 15

10 51 15 19 15

11 51 13 21 15

12 51 11 23 15

13 51 10 24 15

14 51 8 26 15

15 51 6 28 15

4. (Marsh.) Charcoal, 6 parts; sulphur, 19⁄2 parts. For pans. Very beautiful.

In preparing coloured fires for fireworks according to the usual formulæ given in manuals of pyrotechny, it is often important to know the speed at which they burn; as in some cases, such as decorations and lances, they should burn slowly; whereas in others, such as wheels, stars for rockets, and Roman candles, they ought to burn quicker. The foregoing tables are so arranged that every formula with a higher number yields a slower burning mixture than one with a lower number. Thus No. 5 burns quicker than No. 6, and slower than No. 4.

Obs. The ingredients in the above compounds are to be separately reduced to powder and sifted through lawn, after which they should be kept in well-corked wide-mouthed bottles until the time of mixing them for use. The chlorate of potassa, more especially, must be separately treated and cautiously handled, in order to prevent the possibility of explosion from friction whilst it is in contact with combustible matter. The requisite quantity of each of the ingredients being weighed out and placed on a clean sheet of white paper, the whole is to be thoroughly but carefully mixed together with a light hand, by means of a bone or wooden knife. The compound is next lightly packed into small cups or pans for illuminations, or into small pill-boxes for stars and trains, a little priming and quick-match being lastly attached to each. To ensure success the several ingredients must be dry and commercially pure; and though reduced to the state of a uniform powder, care must be taken that they are not absolutely ‘dusty,’ or too finely pulverised. The nitrate of strontia, alum, saltpetre, carbonate of soda, &c., before being weighed, require to be gently heated in an iron pot or pan until they fall to powder, and lose their hygrometric moisture, or water of crystallisation. To ensure the perfect admixture of the ingredients, the whole, after they have been stirred together on paper, as before directed, may be passed through a hair or perforated zinc or brass sieve. Further, as coloured fires rapidly deteriorate by keeping, and even sometimes inflame spontaneously, to prevent disappointment and accidents they should not be prepared long before they will be required for use, and should be stored in some situation in which their spontaneous combustion would be productive of no disastrous consequences.

Of the above formulæ, those bearing the name of the late Mr Marsh, of Woolwich, more especially deserve the attention of the pyrotechnist. To guard against the danger sometimes arising from the spontaneous combustion of coloured fires containing sulphur and chlorate of potash, Mr Saunders recommends intimately mixing 120 grains of bicarbonate of potash with each pound of sulphur before using it in the manufacture of any composition into which chlorates enter. See Flame, Pyrotechny, &c.

FISH. Syn. Pisces, L. Fishes form the fourth class of vertebrate animals (VERTEBRATA) in the Cuvierian arrangement of the animal kingdom, and in the variety of their genera and species are second only to the INSECTA, whilst in prolificness and number they probably exceed all other animated beings that reach a size equal to that of even the smallest member of their prodigious race. Besides their value to man as food, they furnish him with oil, isinglass, and various other articles of utility and luxury, and provide, either directly or indirectly, an inexhaustible supply of manure for the fertilisation of his fields. As food fish are undoubtedly wholesome and nutritious, although less so than the flesh of animals or the grains of the cereals. Of all the various substances used as aliments by man, fish are, however, the most liable to run into a state of putrefaction, and should therefore be only eaten when perfectly fresh or, if not recently taken, then only when their perfect preservation has been ensured by any of the ordinary methods employed for the purpose. Those that are the whitest and most flaky when cooked, as cod, flounders, haddock, hake, soles, turbot, whiting, &c., are the most easily digested; and those abounding in oily matter, as eels, herrings, mackerel, salmon, &c., are most nutritious, though the most likely to offend the stomach. Salt-water fish have been said to be more wholesome than river fish, but without sufficient reason. Salted fish are hard of digestion, unless when carefully cooked and well masticated. Skin diseases are said to be more common among those who live continually on fish than among those who abstain from it; but this probably arises from their use being unaccompanied by a proper quantity of fresh vegetables or fruit, both of which are scarcer on the sea-coast than further inland. As one of the components of a mixed diet, the value of fish is indisputable. Acid sauces and pickles are the proper additions to fish, from their power of retarding the progress of putrefaction, and of correcting the relaxing tendency of large quantities of oil and butter.

Artificial Propagation. The fecundity of fish is positively marvellous. According to the recent observations of Mr Frank T. Buckland, salmon yield about 1000 ova or eggs to every lb. of their weight; a trout weighing 1 lb. produced upwards of 1000; a mackerel (1 lb.), 86,120; a herring (⁄2 lb.), 19,840; a sole (1 lb.), 134,466; a turbot (8 lbs.), 385,200; and a cod (20 lbs.), 4,872,000. The ova here spoken of form what is commonly called the ‘hard roe’ of the female fish; the ‘soft roe’ is ‘the milt’ of the male fish. To protect the spawn, and the fry, when hatched, is the object of the art of fish culture, which has made great progress during late years. When the spawn is not artificially protected, the greater portion is always wasted, being swept away by the stream, and devoured by fish, birds, and insects. The natural enemies of the newly hatched fish are, again, so numerous, that it is really surprising that any should escape destruction. According to given data and accurate calculations of the returns of fisheries made by Messrs Ashworth and Buist, only one salmon egg out of every thousand deposited ever becomes a fish fit for human food. Other fish, both fresh and salt water, suffer in proportion. The hatching of fish by artificial means has been carried out on a large scale in France, and has been commenced in Scotland and Ireland, and on a small scale in England. The spawning fish, having been caught by a net, is made to deposit her eggs by gently pressing on the abdomen; these are impregnated by ‘milt’ expressed from the male fish in a similar manner, and mixed with them in a shallow tub or other vessel prepared for the purpose. The impregnated eggs are placed in long shallow boxes, bottomed with gravel and pebbles, and so arranged that a small stream of water from a reservoir may flow from one to another. The time of hatching depends entirely upon the temperature of the water; from 40° to 45° Fahr. seems to be the healthiest temperature. After about 50 days (in the case of salmon), when all goes well, the young fish makes its appearance as a misshapen creature about an inch long, with a bag containing the yolk of the egg attached to its abdomen. At 3 days old the fry is about 2 gr. in weight; at 16 months it has increased to 2 oz. To preserve the young fish in health, the boxes must be covered with shades of slate or zinc. The French fish-breeders generally feed the young fry with boiled frogs powdered fine. The Scotch give boiled liver. Mr Buckland prescribes a diet of roe of sole, or plaice, or whiting. As to the age at which it is advisable to turn the young fish out of the nursery, there is much difference of opinion. Some breeders recommend turning them out as soon as the ‘umbilical bag’ is absorbed; others think they should be taken care of till they are older and stronger, and better able to defend themselves or escape from attack. For full details respecting the artificial propagation of fish, the reader is referred to Mr Buckland’s recent work, entitled ‘Fish-Hatching.’

Nutritive Value of Fish.—The white varieties of fish, such as whiting, cod, haddock, sole, plaice, flounder, and turbot, according to Letheby, contain only about twenty-two per cent. of solid matter, of which eighteen is nitrogenous. To increase their nutritive value, therefore, these fish should be eaten with butter.

According to the same authority mackerel, eels, and salmon are richer in fat than the above kinds; mackerel containing about seven per cent., and salmon about six, whilst the oily matter of eels amount to nearly fourteen per cent. The same is the case with the sprat, the herring, and the pilchard, as well as with most of our fresh-water fish.

As regards shell-fish, all the different varieties of them afford about the same amount of nutrition. They contain about thirteen per cent. of solid matter, which in composition is similar to that of white fish. Shell-fish vary in digestibility; mussels, limpets, and whelks being rather difficult of digestion, whilst scallops, cockles, periwinkles, lobsters, and crabs are a trifle more easy of digestion, and oysters still more so. All shell-fish are unsuited for delicate stomachs; although they are largely eaten by the poorer dwellers on the coast.

On the Continent, vineyard snails, and in China, slugs, are eaten, and are said to possess a delicate flavour and nutritive properties.

Choice, &c. “The flesh of any fish is always in the highest perfection, or in season, as it is called, during the period of the ripening of the milt and roe. After the fish has deposited the spawn, the flesh becomes soft, and loses a great deal of its peculiar flavour. This is owing to the disappearance of the oil or fat from the flesh, it having been expended in the function of reproduction.” (Fleming’s ‘Phil. Zoology.’) Fish should be dressed as soon after being caught as possible, as much of their peculiar delicacy and flavour is lost by keeping, even for a few hours. Turbot and salmon are said by the fishmongers to be improved in flavour when 2 or 3 days old, but this is surely a mistake, as the former, when dressed immediately after being caught, possesses a fine creamy taste, which it afterwards loses; whilst the latter, by the loss of a single tide, loses a portion of the fine white curd which is previously found between the flakes, and by longer keeping, this curd, with the larger flakes, disappear altogether. In the eyes of some epicures the richness, is however, increased by this change. Mackerel, and some other fish suffer so much from keeping only a few hours, that they become quite unwholesome. Herrings offer a remarkable example of the advantage of dressing fish as fresh as possible. When cooked soon after being caught, they possess considerable delicacy and flavour, but after being kept for only a few hours, the oil separates from the flesh, and they become soft, greasy, and strong-flavoured.

In the choice of every kind of fish, stiffness, brightness of the eyes, and redness of the gills, may be regarded as invariable signs of freshness. A peculiar elasticity will also be perceived in fish recently caught, little or no permanent impression being made by the ordinary pressure of the fingers, from the flesh immediately rising when the pressure is withdrawn. Fresh fish also lie in a partly curled position, and never quite straight, as in the case when they have been kept for some time. Thickness and fleshiness are deemed marks of the good condition of all fish.

Cleaning, dressing, &c. On the proper cleaning of fish preparatory to dressing it, depends much of its delicacy and flavour. Ordinary cooks seldom do this well, from not slitting the fish sufficiently open to permit the inside to be thoroughly washed, and seldom using sufficient water. The superior flavour of fish cleaned by the fishmongers arises from their performing the operation more completely, and from the large quantity of water they employ about them. The flavour of all fish is improved by adding a little salt or vinegar to the last water in which they are washed. The sound, milt, and roe, should be carefully cleaned and preserved.

Fish is preferably ‘dressed’ by simple boiling, broiling, or frying; in fact, the finer kinds of fish are often injured by the excessive interference of the cook. When boiled, “all large fish, with the skin whole, must be placed on the fire in cold water; if crimped, or cut into slices or pieces, in boiling water; if whole, it must not be covered with more than two or three inches of water, or the skin will crack, and not only spoil the appearance of the fish, but will diminish the gelatine and gluten it contains, and instead of eating firm and full of flavour, it will be soft and woolly, especially if over-boiled.” (Soyer.) As soon as a scum rises from boiling, it should be removed by the skimmer. The addition of a little salt or vinegar to the water improves the flavour of most fish, and renders the flesh firmer. The proportions should be “two teaspoonfuls of salt to every quart of water.” “If the fish be whole, as soon as it begins to boil remove the cover on one side, and let it simmer gently until done. (Soyer.) A fish is known to be sufficiently dressed by the flesh in the thicker parts separating easily from the bone. “If a large fish I generally try it by gently pushing a wooden skewer through the thickest part; if it goes in easily it is done.” (Soyer.) When this is the case it should be removed from the kettle, as by soaking in the water fish loses its firmness, and becomes soddened. Sole, skate, and mackerel, are usually put into boiling water, whether whole or sliced. Fish for broiling should be well washed in strong vinegar, wiped dry with a towel, and floured before placing them on the gridiron; and the bars of the latter should be hot, and well buttered. (Rundell.) Fish for frying should be prepared as for broiling, and the butter, oil, or lard should be allowed to boil for a minute or two before putting them into the frying-pan. The latter should be perfectly smooth and bright, and the butter or oil in abundance, to prevent the fish sticking to it and burning. As the fish are cooked solely by the heat of the melted fat, to fry them in the highest perfection there should be enough of it to cover them. Butter or oil is the best for the purpose. To avoid loss, the contents of the frying-pan, after the fish is removed, should be poured into a clean jelly-jar or basin, and reserved for another occasion. The fish being removed from the pan, the superfluous fat should be drained from them preparatory to ‘serving’ them. When fish is divided into fillets or cutlets before being cooked, it is usual to take out the bones, and to dress it with force-meat, &c.

In serving fish of the finer kinds, no other additions are required than melted butter and the ordinary fish sauces and pickles. The dishes are commonly garnished with raw parsley, for the sake of appearance, but boiled parsley, chopped small, should accompany it. All kinds of fish should be served on a napkin.

Caution. It sometimes happens that a fishbone accidentally swallowed remains in the œsophagus, and occasions serious inconvenience; in fact, instances have been known where so much irritation has arisen that death has followed. In such cases it is advisable, as soon as possible, to take of tartar emetic, 4 gr., dissolved in warm water, ⁄2 pint; and immediately afterwards the whites of six eggs. The coagulated mass will not remain in the stomach more than two or three minutes, and the remedy has been known to “remove no less than 24 pins at once.”

FISH GLUE. See Glue and Isinglass.

FISH POISONING. See Accidents.

FISH SKIN. Syn. Shark skin. The skin of the spotted dog-fish or rough hound (chien de mer, Fr.), stretched and dried. Used for polishing wood and ivory. Several other varieties of fish skin are employed in the arts. The dressed skin of the ‘rousette’ (peau de rousette, F.), is transparent, and very beautiful. Cemented on green paper, and rubbed down and polished, it is used as veneer for fancy boxes. The skins of several varieties of Squalus are also used for both the above purposes. See Shagreen.

FIVE HERBS. See Species.

FIX′ATURE Syn. Bandoline, Clysphitique, Eau collante, Fixateur, Fr. This consists of any of the simple vegetable mucilages, combined with a little spirit, to preserve it, and with a little perfume, to render it more agreeable.

Prep. 1. From carrageen, Irish, or pearl moss, soaked in cold water for an hour or two, and after being drained, and pressed dry in a clean napkin, dissolved by boiling in soft water, q. s. The decoction is strained through cambric, and when nearly cold is mixed with about ⁄3rd or ⁄4th of its volume of eau de Cologne or other scented spirit, with the further addition of a few drops (5 or 6) of oil of cloves. Sometimes a little brandy is added to the mucilage, and when it is intended for present use, as is common with home manufactures, the spirit is frequently omitted altogether. ⁄4 oz. of the prepared moss is fully enough for ⁄4 pint of strained decoction, if rightly managed.

2. From quince seed boiled in water, as the last. ⁄4 oz. yields nearly ⁄4 pint of strained decoction.

3. Pale gum arabic (picked), 1⁄2 oz.; rose water, 2 fl. oz.; pure water, 3 fl. oz.; dissolve.

4. Gum arabic, 3⁄4 oz.; water, ⁄2 pint; dissolve, and drop in eau de Cologne, gradually, until the cloudiness at first occasioned ceases to be removed by agitation; the next day decant the clear portion. All of the above are very superior, and keep well.

5. (Redwood.) Gum tragacanth, 1⁄2 dr.; water, 7 oz.; proof spirit, 3 oz.; otto of roses, 10 drops; macerate 24 hours, and strain.

6. Malt, 7 oz.; hot water (that will barely permit the finger to be held in it without pain), ⁄2 pint; infuse in a covered jug or basin, gently press out the liquid, and as soon as cold add of proof spirit (or brandy or Cologne water), 2⁄2 fl. oz. and strain.

Obs. Bandoline is used by ladies and by hairdressers for stiffening the hair, and to make it curl firmly and remain in place. It is applied either by moistening the fingers and passing the hair through them, or by means of a small sponge. See Pommade.

FIXED AIR. See Carbonic Acid.

FIXED OILS. See Fat and Oils.

FLAKE WHITE. See White Pigments.

FLAME. Gas or vapour in an incandescent state. The light emitted from pure flame is exceedingly feeble; illuminating power being almost entirely dependent upon the presence of solid matter. See Illumination, and below.

Flame Colours. The vapours of metallic compounds communicate colours to flames. The characteristic colours of some metals are very beautiful, and their exhibition forms a favorite experiment of chemical lecturers. The coloured flames are generally produced by the combustion of alcohol or rectified spirit upon certain salts in fine powder. In this way a GREEN colour is communicated by boracic acid or chloride of copper; a RED one by the nitrates of iron, lime, or strontia; a VIOLET, by potassa and its salts; and a YELLOW, by nitrate of soda. Messrs Church and Crookes have recently described a mode of exhibiting the characteristic flames of the metals which is admirably adapted for the lecture-table. ‘Gun-paper,’ made in the same way as ‘gun-cotton,’ is to be soaked in solutions of the chlorates of the different metals, dried with care, and kept dry. A good ‘gun-paper’ for the purpose is prepared by soaking strips of Swedish filtering-paper for ten minutes in a mixture of 4 parts oil of vitriol with 5 parts strong nitric acid, both by measure. The strips, when taken out of the acid, should be washed first with cold, and then with hot rain or distilled water, till the washings are no longer sour to the taste. The solutions of the metallic salts need not be very strong; but if they are warm, the strips of ‘gun-paper’ will be more easily and completely saturated with them. Since some of the chlorates attract moisture from the air, it is better to dry the papers prepared with them before the fire previous to lighting them. They are shown to best advantage when a strip is loosely crumpled up into a pellet, lighted quickly at one corner, and thrown up into the air against a dark back ground. They leave after burning, if properly prepared, no ash whatever. Paper prepared with the salt of potassa gives a flash of VIOLET flame, that prepared with the soda salt the characteristic YELLOW flame, and that with chlorate of baryta a very beautiful GREEN light. The chlorates of strontium, lithium, and calcium, when thus ignited, give intense colours. The VIOLET-BLUE flame of copper is well seen, even with the chloride of that metal, while paper soaked in nitrate of potassa shows the potassium flame better than if the chlorate be used. ‘Gun-paper’ prepared with a very weak solution of chloride or chlorate of thallium shows the characteristic SPRIG-GREEN flame of that metal with great distinctness. Chlorate of barium, being an article of commerce, may be employed for the preparation of the other chlorates, it being merely necessary to add to this salt in solution an exactly equivalent quantity of the sulphate or carbonate of the metal whose chlorate is desired. For instance, in order to make ‘chlorate of copper,’ 15·1 gr. of chlorate of barium being dissolved in hot distilled water, a boiling solution containing 12·5 gr. of pure crystallised sulphate of copper is to be added to it. Insoluble white ‘sulphate of baryta’ falls, while the solution, filtered and evaporated, yields the new chlorate in crystals. See Fires, Pyrotechny, &c.

FLAN′NEL. It has been shown by the experiments of Count Rumford that the conducting power of the different materials employed for clothing varies considerably. A thermometer surrounded with cotton wool, and heated by immersion in boiling water, took 1046 seconds to lose 135° Fahr., when plunged into a bath of melting ice; but, under the same circumstances, when sheep’s wool was employed, 1118 seconds elapsed before a like sinking of the thermometer took place (‘Phil. Trans.,’ 1792); thus showing the greater conducting power of the former, and consequently the superiority of the latter substance for the manufacture of warm clothing. But the chief advantage of wool, as an article of underclothing, depends less upon its actual power of conducting heat than its peculiar texture. Flannel acts as a gentle stimulus on the skin, and exercises the most beneficial action, by keeping the pores clean, and in a state most favorable to perspiration. This action is a species of friction similar in character, although inferior in degree, to that of the common flesh-brush or horse-hair glove, so long employed as a skin stimulant. Flannel has also the advantage of absorbing the perspiration as soon as emitted, and allowing its watery portion to pass off into the atmosphere almost as soon as formed, but this is not the case with cotton and linen fabrics. The different effects of flannel and linen are particularly susceptible during brisk exercise. When the body is covered with the former, though perspiration be necessarily increased, the perspired matter freely passes off through the flannel, and the skin remains dry and warm. If the same exercise be taken in linen shirts, perspiration, as in the former case, is indeed also increased, but the perspired matter, instead of being dispersed into the atmosphere, remains upon the linen, and not only clogs the pores of the skin, but gives a disagreeable sensation. From this property of flannel, persons who wear it next the skin seldom catch cold from changes of temperature, even though perspiring profusely; but in similar cases, when linen or calico shirts are worn, chilliness immediately comes on, followed by sniffling, sneezing, and cough, and all the other symptoms of severe catarrh.

The common objections raised against the use of flannel are founded on vulgar prejudices, ignorance, obstinacy, or bravado, and are undeserving of the notice of sensible people. In a fickle and moist climate like that of England, every person should wear a robe of flannel next the skin, or at all events a waistcoat of flannel reaching below the loins; and this should not be discarded as soon as the cold weather has passed, but its use should be continued all the year round; for in reality flannel is, if possible, even more required in summer than in winter, because persons perspire more freely in hot than in cold weather, and are consequently more susceptible of cold, while at that period of the year their clothing is less capable of protecting them from the effects of sudden changes of temperature and draughts of cold air, moisture, &c. Females, children, persons of delicate constitutions, and all others who from their habits of body or life perspire freely, or are much exposed, should wear flannel.

In washing flannels it is recommended that they should only be put into warm water, by which method their colour will be preserved, and they will be prevented from shrinking.

FLASH. Prep. From burnt-sugar colouring, 1 gall.; fluid extract of capsicum or essence of Cayenne, ⁄4 pint, or enough to give a strong fiery taste. Used to colour spirits, and to give them a false strength. It is made by the brewers’ druggists, and labelled ‘ISINGLASS AND BURNT SUGAR,’

FLASKS. The late lamented and ingenious Mr Fownes suggested the employment of Florence oil-flasks as cheap substitutes for retorts, receivers, digesters, and some other vessels used for chemical purposes. His plan was to cut the neck smoothly round with a hot iron, and softening it in the flame of a good argand gas-lamp, to turn over the edge so as to form a lip, or border. The neck will then bear a tight-fitting cork without splitting.

FLATULENCE. Syn. Flatulency, Wind. In pathology, a morbid collection of gas in the stomach and bowels. Its most common cause is indigestion. When the natural fluids of the stomach are secreted in a healthy state, they exercise an antiseptic and digestive action on the food, by which it is speedily reduced to a magma that is little liable to spontaneous change whilst in the body; but when the reverse is the case, fermentation soon commences, and the stomach and associated viscera become distended with gas, and all the well-known symptoms of flatulency are developed in rapid succession. The quantity of gas thus accumulated in the ‘primæ viæ’ is often enormous. An ordinary apple during fermentation yields about 600 times its bulk of gas, and many vegetables yield much more. (Dr Hales.) It is, therefore, not at all surprising that so much inconvenience should be felt when the food, instead of being digested and assimilated, runs into the state of active fermentation.

The treatment of flatulency consists mainly in the selection of proper articles of food. Oleraceous vegetables, peas, beans, under-dressed potatoes, and indigestible fruits should be especially avoided, as well as the use of large quantities of weak or warm liquids. The diet should consist principally of animal food, carefully but not over-cooked, with a sufficient quantity of good mealy potatoes (mashed, not whole), and good wheaten meal-bread, moderately seasoned with common salt and spices. The most suitable beverages are toast-and-water, and a little good brandy largely diluted with water. The healthy tone of the stomach may be re-established by the proper use of tonics, bitters, and mild aperients.

To relieve the fit of flatulency, carminatives and aromatics, as black pepper, mustard, peppermint, ginger, cinnamon, lavender, and most spices, may be had recourse to. A glass of peppermint cordial, or of brandy strongly flavoured with peppermint or ginger, is a popular and efficient remedy. A few drops (15 to 30) of ether, with a little tincture of capsicum or spirit of sal volatile, seldom fail to give relief. See Dyspepsia.

FLAVOURING SUBSTANCES. See Essence, Oil (Volatile), Spice, Wine, &c.

FLAX. See Linen, Linseed, and Oil.

FLEA. This troublesome little animal is the Pulex irritans of Linnæus, and belongs to the Suctoria, or fourth order of the Insecta. Its favorite haunts are our warm underclothing, and its most productive breeding-places are in the ‘flue’ which careless servants allow to accumulate underneath our beds. Cold, light, perfumes, and ventilation, are inimical to its propagation.

FLECHTENKAPSELN (Tetter Capsules, or Dr Berkeley’s Antiherpetic Capsules for Skin Diseases, Tetter, &c.) Capsules filled with tar. (Hager.)

FLECHTENMITTEL—Tetter Cure. (Paris). 1. A Washing Fluid.—Common water, containing 1⁄2 per cent. sulphuric acid. 2. A Salve. A mixture of lard and spermaceti, with ⁄24 of their weight of calomel. (X. Schmidt.)

FLECHTENPULVER—Tetter Powder (St Lube’s, France). Nitre, 100; antimony chloride, 10; antimony oxide, 200, 1·5 grammes for a dose. (Wittstein.)

FLECHTENSALBE—Tetter Salve (Fontaine, Paris). For all skin diseases. Olive oil and white wax, with ⁄16 of white precipitate. (Wittstein.)

Flechtensalbe (Bruno Reichel, Apolda). A mixture of wax and lard coloured green. (Schädler.)

Flechtensalbe (F. Schwarzlose, Berlin, and S. G. Schwartz, Breslau). For salt-flux, tetters, and similar skin diseases. Peru balsam, 1; carbolic acid, 2; yellow wax, 10; lard, 30. (Schädler.)

Flechtensalbe (Surbi, Paris). For all kinds of skin diseases. A mixture of beef tallow, 30; olive oil, 10; zinc oxide, 2; steatite, 2. (Wittstein.)

FLECHTENSEIFE, Tetter Soap (Dr Berkeley). Ordinary tar soap. (Hager.)

FLECHTENWASSER. The wonderful wholesome mineral vegetable tetter-water (Dr A. von S.). Corrosive sublimate, ·25 grammes; water, 180 grammes; benzoin tincture, 6 grammes. (Weber.)

FLECKENWASSER (Bronner). Cleansing fluid (literally spot or stain water) for the removal of grease and dirt spots. Benzine only.

Fleckenwasser, Englisches (English cleansing fluid for removing acid, resin, wax, tar, and grease spots.) A mixture of 95 per cent. alcohol, 100 grammes; liq. ammon., sp. gr. ·875, 30 grammes; benzine, 4 grammes. (Artus.)

FLEISCH-EXTRACT-LIQUEUR (Eau de Vie Alimenteuse—Extract of Meat Liqueur—Aqua Vitæ Incarnativa) (A. Hensel, Berlin). A beautiful red spicy liquor, leaving, when distilled, 32 per cent. of solid matter. This residue contains in 100 parts (besides anilin-red), resin and extractive (partly from ginger and partly from cinnamon), 3⁄4; sugar, 27⁄2; extract of meat, 1⁄4. (Hager.)

Fleisch-Extract-Syrup (Syrup of Extract of Meat) (Meyer, Berk). Blood-serum made into a syrup with sugar. (Hager.)

FLEISCHFASER-ZWIEBACK FÜR HUNDE—Fibrin Dog Biscuits (New York). Said to be made of pure meal, fibrin, dates, and other ingredients, and recommended as an excellent food for dogs. According to the prospectus its use makes all other foods unnecessary, as it gives the animals peculiar endurance, strong muscles, and sound bones. The directions for use say that it is most advantageously given in its unprepared form, as dry, heavy, hard cakes, and only in case it is refused should it be softened for a short time in cold water. According to the analysis performed in the laboratory of the Poppelsdorf Agricultural Academy the proportion of nitrogenous to non-nitrogenous ingredients is 1 to 3·70. Microscopic analysis detects the presence of dried fibrin, and also a considerable admixture of structureless hyaline cartilaginous matter. From this it follows that the nitrogen revealed by analysis does not all represent protein or fibrin, and that the proportion which arises from indigestible gelatinous matter will be of smaller value. (Dr E. Kern.)

FLESH. Syn. Caro, L. The muscular substances of animals; the softer, solid portions of the body, as distinguished from the bones and fluids. See Fibrin, Food, &c.

Flesh-brush. This simple instrument is used for exciting the cutaneous circulation. Those which have the bristles set on a leather back are esteemed the best. The flesh-glove or hair flesh-rubber is a useful modification of the common flesh-brush. Those manufactured by Messrs Savory and Moore, in imitation of the Indian kheesah or mitten, are superior to all others. In the absence of both flesh-brush and glove, a rough towel wound round the hand is no bad substitute. See Friction.

FLIEGENPAPIER, GIFTFREIES—Non-Poisonous Fly Papers (Bergmann & Co., Rochlitz). Contains abundance of arsenious acid. (Hager.)

FLIEGENPULVER—Fly Powder (Baumann, now Markel, Austria). 93 to 94 per cent. of dry sandy ferruginous clay (ordinary loam) saturated with a decoction of some bitter substance, as quassia or gentian. (Hager.)

FLIES. See Fly.

FLIP. See Egg Flip.

FLÖHEMITTEL—Flea Powder (Leipsic). Powdered soap. (Fischer.)

FLÖHEWASSER—Flea Water (Koch, veterinary surgeon, Vienna). 7 brandy, 1 benzine, 1 black soap. (Hager.)

FLORILINE—Vegetable Tooth Paste made by John Yates (Albin Müller, Brünn). It is contained in a quadrangular china pot, and is a red, dry, rather hard mass made from prepared chalk, 20 grammes; starch powder, 10 grammes; glycerin, 8 grammes; pellitory tincture, 3 grammes; peppermint oil, 10 drops; and water q. s., coloured with Florentine lac. (Hager.)

FLOUN′DER. A flat fish, very like the plaice, but smaller, and of more obscure colour. It is very common about the British coast, and is found in the Northern, Baltic, and Mediterranean seas. Its flesh is very wholesome.

FLOUR. Syn. Farina, L. The finely ground and ‘dressed’ meal of bread corn, and of the seeds of some of the leguminosæ. That known specifically as ‘flour’ in this country is obtained from spring varieties of Triticum vulgare (the common wheat).

Var., &c. Of varieties of flour there are several, depending chiefly on the amount of bran which they contain, and the relative fineness of the sieves through which they are passed:—

Fine wheat flour, Pastry flour; Farina, F. tritici, F. seminis tritici. The finest flour, obtained from the meal produced in the first grinding of wheat between sharp stones, by means of a sieve of 64 wires to the inch. Used for pastry.

Middlings. The remainder of the flour of the first grinding, obtained by means of a slightly coarser sieve. Used for making household bread, but is mostly reground for the next variety.

Seconds. The finest part of the flour, obtained by regrinding ‘middlings’ between blunt stones. Used by the bakers for their finest wheaten bread.

Pollard. The coarse flour, from which the seconds has been sifted. Used for making sea biscuits and gingerbread, and to fatten poultry and hogs.

Country household flour. This is usually ground only once, and sifted to ⁄5ths of the weight of the wheat.

Ammunition flour is ground and sifted to nearly ⁄6ths the weight of the wheat.

According to Mr Accum, thirty-two pecks of wheat in the London mills yield, of flour 38⁄2 parts; pollard, 8 parts; and bran (furfur tritici), 12 parts; the bulk of the wheat being doubled by grinding.

According to Mr Hard, miller, of Dartford, quoted by Dr Pereira, the wheat having been ground in the usual way, is allowed to remain in the state of meal for some time before ‘dressing,’ which removes the heat caused by the process, and enables the miller to obtain more flour, and the baker a better quality, than if ‘dressed’ immediately it is ground.

“The process of dressing is by a wire cylinder containing a certain number of sheets of different texture or fineness, which cylinder contains eight hair brushes attached to a spindle passing through the centre of the cylinder, and laid out so as to gently touch the wire. This cylinder is fed by a ‘shoe’ with the meal; then the ‘flour’ and ‘offal,’ after passing through the wire in this way, are divided by wooden partitions fixed close to the outside of the cylinder.” “The produce of the wheat-meal dressed through the wire machine consists of—1, Flour;—2, White Stuff, or Boxings, or Sharps;—3, Fine Pollard;—4, Coarse Pollard, or Horse Pollard;—5, Bran. The 2nd product (i. e. the white stuff) is then submitted to another ‘dressing’ through a fine cloth machine, and produces—1, Fine Middlings, for biscuits;—2, Toppings, or Specks;—3, Dustings;—4, Best Pollard, Turkey Middlings, or Coarse Middlings.

Table of the Produce of One Quarter of Wheat
(= 504 lbs.) By Mr Hard.

Flour 392 lbs.

Biscuit or fine middlings 10 ”

Toppings or specks 8 ”

Best pollard, Turkey p., or twenty-penny 15 ”

Fine pollard 18 ”

Bran and coarse pollard 50 ”

Loss by evaporation and waste 11 ”

504 ”

Analysis of Flour.

Peligot. Mean of 14 Analyses. Letheby. Payen. Wanklyn. Fine Wheaten Flour.

Per cent. Per cent. Per cent. Per cent.

Water 14·0 15·0 14·22 16·5

Fat 1·2 2·0 1·25 1·2

Nitrogenous matters, gluten, &c. 12·8 10·8 14·45 12·0

Ditto, soluble in water 1·8 — — —

Non-nitrogenised substances, dextrin, sugar, &c. 7·2 70·5 68·48 69·6

Starch 59·7

Cellulose 1·7

Salts (ash) 1·6 1·7 1·6 0·74

According to Vauquelin, French wheat flour contains about 10% of water, 11% of gluten, 71% of starch, 5% of sugar, and 3% of gum; and the water of the dough amounts to about 50%. The quantity of the bran in wheat ranges under 2%.

Pur. This article of food is very frequently adulterated both by the miller and the baker, as has been before alluded to in the article on bread. The principal physical characteristics of wheat flour of good quality are the following—it has a dull white colour, somewhat inclining to yellow;—it exhibits no trace of bran, even when pressed smooth with the hand, or with a polished surface;—its cohesiveness is so great that, on being squeezed in the hand, the lump is some time before it loses its shape;—it has a homogeneous appearance, and does not lose more than from 6% to 12% by being carefully dried in a stove. The smaller the loss in this way the finer is the quality, other matters being equal, and the more economical in use. (See below.)

Tests. 1. Solution of ammonia turns pure wheat flour yellow; but if any other corn has been ground with it, pale brown; or if peas or beans have been ground with it, a still darker brown.

2. Solution of potassa, containing about 12% of caustic alkali, dissolves pure wheat-flour almost completely; but when it is adulterated with the flour of the leguminous seeds (beans, peas, &c.), the cellulosæ of these substances remains undissolved, and its hexagonal tissue is readily identified under the microscope. Mineral substances (chalk, plaster of Paris, bone dust, &c.) are also insoluble in this test, and appear as a heavy white sediment.

3. Boiling water poured on the sample causes the evolution of the peculiar odour of pea or bean flour when these substances are present. Bread made with such flour evolves a like odour on being toasted.

4. Pure hydrochloric acid poured on potato flour, or on wheat flour adulterated with it, develops a smell of rushes; it also dissolves starch, but changes the colour of pure wheat-flour to a deep violet.

5. Nitric acid turns wheat flour of an orange-yellow colour, but forms a stiff and tenacious jelly with potato fecula, the colour of which it does not alter.

6. A portion of the suspected sample submitted to dry distillation in a stoneware retort, and the distillate collected in a receiver containing a little water, the latter is found to remain perfectly neutral if the wheat flour is pure, but acquires a distinctly alkaline reaction when beans, pulse, or pea meal is present. (Rodrigues.)

7. Triturate 300 gr. of the sample with an equal weight of clean siliceous sand, and after five minutes form a homogeneous paste with water; afterwards further adding more water, until about 2 fl. oz. have been used. The filtered liquid, treated with an equal quantity of a strong and pure aqueous solution of iodine, develops a pink colour, which gradually disappears when the specimen examined consists of pure wheat flour; but assumes a deep-purple colour, which disappears much more slowly, if the flour is adulterated with even 10% of fecula or potato flour. This test succeeds, not only with flour and meal, but also with macaroni, vermicelli, &c. (M. Chevallier.)

8. The milky liquid holding the starch in suspension (see Anal., page 749) is poured into a small conical glass, and left at rest for some time; the clear liquid is then decanted, and any remaining water carefully sucked up with a pipette, and the whole left for some time, in order that the deposit may harden. The upper gray layer is next removed with a teaspoon, and the harder and stiffer second layer left undisturbed until it becomes quite solid by drying. When in this state, it may be upset in the form of a cone, upon a lump of dry plaster. The fecula or potato starch (if any is present), being heavier than that of wheat, forms the apex of the cone, and its quantity may be estimated in the following manner:—The operator cuts from the apex of the little cone above mentioned a slice, which he triturates only for a short time in an agate mortar (one of glass, or porcelain, or wedgwood-ware, will not do), and he tests that with aqueous solution of iodine. If it turns blue, it is fecula. Another slice is treated in the same manner, until the operator comes to the wheat starch, which, in the present instance, is not affected by the aqueous solution of iodine. This difference of behaviour of the two species of starch with iodine is due to the friction of the pestle and mortar, which is sufficient to divide or tear the envelopes of the particles of the potato starch, which then become blue when treated by solution of iodine. The particles of wheat starch, on the contrary, are not disaggregated by that treatment, and being therefore protected by their envelope, are not acted upon by the solution of iodine, or, at most, assume only a brown tinge. (M. Robine.)

9. Wheat flour adulterated with plaster of Paris, ground bones, chalk, and potato flour, has a higher specific gravity than a sample of the pure flour. This may be readily ascertained by any person by filling a small vessel with some pure flour, and then with the given sample. “A vessel which will contain 1 lb. of wheat flour will contain 1⁄2 lb. of fecula” (potato flour), and hence “the proportion of this adulteration may be easily estimated.” (Ure.)

10. If to a sample of wheat flour is added a solution of potassa, containing about 1⁄4% of the pure alkali, the granules of potato farina, or of bean meal, or pea meal, present (if any), will acquire 4 or 5 times their original volume, while those of the pure wheat starch will be scarcely affected by it. This change is very perceptible under a microscope of small power. 2 parts of liquor of potassa (Ph. L.) and 5 parts of distilled water form a mixture that answers for the above purpose.

11. By means of the microscope the admixture of the cheaper feculas and meals with wheat flour is readily detected by the characteristic appearance of the starch grains; and when the adulteration exceeds 9% or 10%, its extent may be readily estimated with considerable accuracy. As the range of adulteration is generally from 12% to 27%, this method is applicable in the greater number of cases.

Analysis. The value of wheat flour as an aliment depends upon the quantity of gluten, sugar, starch, and phosphate of lime, which it contains; and its superiority over the flour of the grains of the other cereals is referred to its containing a larger proportion of the first and last of these substances than they do. The quantitative analysis of flour is very simple, and may be easily made by persons unacquainted with chemistry, by attending to the instructions below:—

a. Make 1000 gr. of the sample into a dough with a little water, let it rest an hour and then gently knead it in successive water, until the starchy particles are perfectly removed. Collect the portion (GLUTEN) left in the hand, drain off the water, place it on a piece of filtering or blotting paper, several times doubled, and set it aside.

b. Mix the several waters employed in the preceding process, and set them aside in a tall vessel, to deposit the suspended portion (STARCH). After a sufficient time pour off the clear liquid, and throw the whole of the sediment on a weighed paper filter, placed in a funnel, observing to remove the portion adhering to the bottom of the vessel by means of a little clean water, that none may be lost.

c. Evaporate the decanted liquid, as well as what runs from the filter, until it becomes curdy, then filter it through a piece of weighed blotting paper, and preserve the sediment (ALBUMEN); next evaporate the residuum to the consistence of a syrup, agitate it with 10 times its weight of alcohol, and filter, observing to wash the paper filter clean with a little alcohol after the solution has passed through it. The substance on the paper is PHOSPHATE OF LIME and GUM, and must be set aside. By subsequent digestion in water, filtration, and evaporation, the two may be obtained separately.

d. Evaporate or distil off the spirit from the solution and washings, as above; the residuum is SUGAR.

e. Dry the substances educed as above, by a gentle heat, and weigh them. The weight of the albumen may be taken with that of the gluten, as it possesses about the same nutritive value, and also because it has been asserted by some persons that the former substance is in reality gluten, and not albumen. By dividing the given weights by 10, the per-centage value of the sample is obtained. The pieces of filtering paper employed should be carefully dried and weighed before using them, and the same degree of heat should be employed for this purpose as that to which they will be afterwards exposed in the drying of the substances resulting from the operations.

Obs. The above method of ascertaining the actual value of any sample of flour as an article of food, though not strictly accurate, approximates sufficiently to the truth for all practical purposes, and is well adapted to the wants of the baker and large purchaser. In many cases it will only be necessary to perform the first part of the process (a), which will give the per-centage of the most important constituent of the flour; the rest being of minor consequence.

In addition to what has been already stated in the article on Bread, it may be useful to mention that a pound of the best flour, from thoroughly dried wheat, will take 10 fl. oz. of water to form it into ordinary dough, or 9 fl. oz. to form it into bread dough. Under the old parliamentary acts, a sack of flour (280 lbs.) was presumed to produce 80 loaves (quartern or quarter-peck), the weight of which, within 48 hours after being baked, was to be 4 lbs. 5⁄2 oz. each. At the present time fully 92 loaves, weighing 4 lbs. each, are produced by the London bakers from one sack of flour, when honest weight is given; but as the latter is rarely the case, and the bread is frequently ‘slack’ or ‘under-baked,’ and thus contains more water than good bread ought to do, a much larger product is commonly obtained. The dough loses about ⁄7th of its weight in baking, if in batches; but fully ⁄6th, if baked in small loaves, and placed in the oven separately. The best bread contains about ⁄4-⁄6th of its weight of added water; and common bread, often much more than ⁄4th. The proportion of water in the London bread has greatly increased during the last few years, owing to the introduction of the fraudulent plan of making the dough with rice jelly or moss jelly. This is the reason why the bread of some bakers suffers such a loss of weight in a few hours after being taken from the oven. A 4 lbs. loaf of bread purchased from a baker at Lambeth, after remaining on the sideboard of a sitting-room for 24 hours, was found to have lost no less than 6⁄2 oz. by evaporation, and in two days longer its interior cells were covered with green mould, and the whole was unfit for food. The bakers, aware of these facts, are particularly careful not to bake more bread than they can dispose of whilst ‘new,’ and are in the habit of refusing to weigh their bread before selling it, when it is more than 10 or 12 hours old, although they are liable to be ‘fined’ for such a refusal. See Bread, Cakes, Farina, &c., also below.

Flour, Baked. Syn. Farina tosta, F. tritici tosta, L. Prep. From wheat flour, carefully baked in a ‘slack’ oven, until it acquires a pale-buff hue. Astringent; used to make food for infants troubled with diarrhœa. See Farina.

Flour, Barley (Prepared). Syn. Farina hordei preparata, L. Prep. (Ph. Bor.) From barley flour, compressed into a tin cylinder until the vessel is 2-3rds full, which is then suspended at the upper part of a still 2-3rds filled with water, and after the ‘head’ is fitted on, the water is kept boiling for 30 hours (2 days of 15 hours each). Lastly, the upper layer being removed, the rest is reduced to powder, and kept in a dry place.

Flour, Boiled. Syn. Triticina, Farina Preparata, L. Prep. From fine flour, tied up in a linen cloth as tight as possible, and after it has been frequently dipped into cold water, the outside of the cloth is dredged over with flour, until a crust is formed round it, to prevent the water soaking into it whilst boiling; it is then boiled for a long time, and when cold, it is divided into small oblong pieces. For use, it is reduced to powder, either by grinding or grating it, and is then prepared like arrow-root. It forms a good diet for children, in diarrhœa, &c.; and as it may be easily prepared at home, it has the advantage of being free from adulteration.

Flour, Jones’s Patent. Prep. From kiln-dried flour, 1 cwt.; tartaric acid, 10⁄2 oz.; mix thoroughly; after 2 or 3 days, add, of bicarbonate of soda, 12 oz.; lump sugar, ⁄2 lb.; common salt, 1⁄2 lb.; mix, and pass the compound through the ‘dressing-machine.’ It is necessary that the whole of the ingredients should be perfectly dry, and separately reduced to fine powder before adding them to the flour. By simply mixing it with cold water, and at once baking it, it produces light, porous bread.

Obs. We have already had occasion to pay a passing tribute to the excellence and usefulness of Jones’s Patent Flour. It is, indeed, invaluable to every household, as furnishing the means of producing, with great economy, and extemporaneously, not merely cakes, puddings, pastry, and fancy bread, but the ‘staff of life’ itself, household bread, of a purity, flavour, and lightness, seldom, if ever, met with in that purchased of the bakers.

Flour, Sewell’s Patent. a. (No. 1.) Flour, 1 sack (280 lbs.); hydrochloric acid (sp. gr. 1·14), 45 oz.; mix, by adding the acid in a ‘spray,’—b. (No. 2.) To the last, add (expertly) bicarbonate of soda, 39 oz.; mix thoroughly, and pass the whole through a sieve or ‘dressing machine.’

Obs. This flour is used as the last, to which, however, it is inferior in quality. No. 1 will keep 5 weeks. No. 2 will keep a month. Jones’s flour will keep good in a dry place for years. If No. 1 is alone employed for the dough, to each pound of the flour, 65 gr. of bicarbonate of soda, with salt q. s., must be added. The patentee claims for his invention the merit of the soda and acid being converted into culinary salt in the process of making up the flour and baking the dough.

FLOWER DEW (F. J. Weber, successor of Rau, Bamberg). A flat bottle with the name of Rau moulded on it; its gross weight is more than 80 grammes, but it contains scarcely 22 grammes of a nearly colourless but slightly yellow fluid, consisting of a pleasant aromatic solution of oils of bergamot, lemon, orange flowers, and rose in strong spirit.

FLOWERS. Syn. Flores, L. These beautiful and fragrant ornaments of our gardens and our dwellings are too highly esteemed by all classes of the community to require anything in favour of their cultivation to be said here. Our remarks will, therefore, chiefly refer to their collection, improvement, and preservation.

‘Full’ or ‘double flowers,’ or those in which the internal organs become petals, are so much more beautiful than the ‘single flowers’ of the corresponding species and varieties, that their production, with tolerable ease and certainty, has long been a desideratum with both the professional and amateur florist. Various plans have been proposed having this object in view, among which are the following:—1. The use of the best seed only, but not before it is at least 3 or 4 years old. 2. The selection of the outer row of seed only, and its careful preservation intact for at least 2 seasons before sowing it. We are assured that this method is particularly successful with dahlias. 3. The removal of the plants to a shady situation as soon as the flower-buds begin to develop themselves, and stinting them with water and nourishment for a few weeks. In this method a few only of the buds are permitted to mature; the rest being snipped off with a pair of scissors as early as possible. 4. The use of small pots and a scanty supply of water until the flowers are partly developed, when water is supplied in abundance, with or without the addition of a little liquid manure.

To hasten the blooming of flowers, it is a common practice with some gardeners to grow them in as small pots as is consistent with their healthy existence, and carefully to avoid transplanting them to larger pots, for several weeks before their usual time of blossoming. A plant on the point of flowering, if transferred to a larger pot and a richer soil, immediately commences making roots and leaves, whilst the embryo flowers either wholly decay, or their development is checked until the usual season of their production has passed over.

The following liquid has been used with great advantage to promote the vigorous growth and the early flowering of plants:—Sulphate or nitrate of ammonia, 4 oz.; nitrate of potassa, 2 oz.; sugar, 1 oz.; hot water, 1 pint; dissolve and keep it in a well-corked bottle. For use, put 8 or 10 drops of this liquid into the water of a hyacinth glass or jar, for bulbous-rooted plants, changing the water every 10 or 12 days. For flowering plants in pots, a few drops must be added to the water employed for them. The preference should be given to rain water for this purpose. The fluid sold under the name of liquid guano may be used in the same manner.

Flowers may be preserved in a fresh state for a considerable time, by keeping them in a moist atmosphere. When growing on the parent stem, the large amount of evaporation from the surface of their leaves is compensated for by an equivalent proportion of moisture supplied by the roots; but when they are plucked, the evaporation from the surface continues, while the supply of moisture is cut off. To supply, in part, this loss of moisture by evaporation, has arisen the almost universal practice of placing flowers in water; but their mutilated stems possess a far inferior power of sucking up fluids to that of the roots, and thus their decay is only deferred for a time. To preserve them more effectually, or at least to render their existence less ephemeral, we may surround them with a moist atmosphere, by which the loss of water from the surface of their leaves will be reduced to the smallest possible amount. “It is now eighteen years ago since we first saw, in the drawing-room of a gentleman, in the hot dry weather of the dog-days, flowers preserved day after day in all their freshness by the following simple contrivance—A flat dish of porcelain had water poured into it. In the water a vase of flowers was set; over the whole a bell-glass was placed, with its rim in the water. This was a ‘Ward’s case’ in principle, although different in its construction. The air that surrounded the flowers being confined beneath the bell-glass, was kept constantly moist with the water that rose into it in the form of vapour. As fast as the water was condensed it ran down the sides of the bell glass back into the dish; and if means had been taken to inclose the water on the outside of the bell-glass, so as to prevent its evaporating into the air of the sitting-room, the atmosphere around the flowers would have remained continually damp. We recommend those who love to see plenty of fresh flowers in their sitting-rooms in dry weather to adopt this method. The experiment can be tried by inverting a tumbler over a rose-bud in a saucer of water.” (‘Gardener’s Chron.’)

Another method by which some flowers may be preserved for many months is to carefully dip them, as soon as gathered, in perfectly limpid gum water, and after allowing them to drain for 2 or 3 minutes, to set them upright, or arrange them in the usual manner in an empty vase. The gum gradually forms a transparent coating on the surface of the petals and stems, and preserves their figure and colour long after they have become dry and crisp.

Yet another method (given in the ‘Pharmaceutical Journal’) is as follows:—“A vessel with a movable cover is provided, and having removed the cover from it, a piece of metallic gauze of moderate fineness is fixed over it, and the cover replaced. A quantity of sand is then taken sufficient to fill the vessel, and passed through a sieve into an iron pot, where it is heated with the addition of a small quantity of stearin, carefully stirred so as to thoroughly mix the ingredients.

“The quantity of stearin to be added is at the rate of half a part to 100 parts of sand. Care must be taken not to add too much, as it would sink to the bottom and injure the flowers. The vessel with its cover on and the gauze beneath it is then turned upside down, and the bottom being removed, the flowers to be operated upon are carefully placed on the gauze and the sand gently poured in, so as to cover the flowers entirely, the leaves being thus prevented from touching each other. The vessel is then put in a hot place, such, for instance, as the top of a baker’s oven, where it is left for 48 hours. The flowers thus become dried, and they retain their natural colours. The vessel still remaining bottom upwards, the lid is taken off, and the sand runs away through the gauze, leaving the flowers uninjured.

Faded flowers may be generally more or less restored by immersing them half-way up their stems in very hot water, and allowing them to remain in it until it cools, or they have recovered. The coddled portion of the stems must then be cut off, and the flowers placed in clean cold water. In this way a great number of faded flowers may be restored, but there are some of the more fugacious kinds on which it proves useless.

Flowers may be produced in winter by taking up the plants, trees, or shrubs in the spring, at the time when they are about to bud, with some of their own soil carefully preserved around the roots, and placing them upright in a cellar till Michaelmas; when, with the addition of fresh earth, they are to be put into proper tubs or vessels, and placed in a stove or hot-house, when they must be treated in the usual manner. By this method, in the month of February, fruits or roses will appear. Flowers sown in pots about Michaelmas may thus be made to bloom at Christmas.

The apparently instantaneous flowering of plants, exhibited a few years ago by M. Herbert to an astonished audience, was, we believe, effected by the heat generated by fragments of quicklime concealed in the mould close to, but not in immediate contact with, the roots. The plants selected by M. Herbert—a group of geraniums and a rose tree—were planted in two rather deep boxes of garden mould, and were covered with glass shades. The operator commenced by pouring over the roots, from a small watering-pot, a liquid which, uniting to the ingredients already in the earth, caused a great heat, as was shown by an intense steam or vapour, which was evolved within the shades, and allowed, to some extent, to escape through a small hole in the top, which at first was kept closed. The effect upon the geraniums was certainly almost instantaneous; the buds beginning to burst in about five or six minutes, and the plants being in full bloom within ten minutes, when the blossoms were gathered by M. Herbert, and distributed amongst the ladies present. With the rose tree the exhibitor was less fortunate. The invention may prove useful where ladies require to decorate their drawing-rooms or boudoirs with the beauties of the floral world somewhat earlier in the season than they can otherwise be obtained. It must not, however, be forgotten that the plants are, as it were, parboiled during the process, and die after a few days.

As regards the sanitary value of flowers, Mantegazza, of Pavia, states that ozone is generated in larger quantities by certain plants possessing spicy aromatic odours, than by the action of electricity upon the air. He says that in some plants this ozone is developed by the direct rays of the sun, whilst in others the action, once begun in solar light, is continued in darkness; and that cherry-laurel, clove, lavender, mint, lemon, fennel, narcissus, heliotrope, hyacinth, mignonette, &c., all produce ozone largely on exposure to the rays of the sun. He also finds that whilst the ozonigenic properties of flowers reside mainly in their perfumes, the most odoriferous yielding the largest amount of ozone, certain others possessing no particular perfume, have extraordinary ozonigenic power; as, for instance, the sunflower, broad belts of which were planted by the late Commodore Maury around the grounds of the national observatory at Washington, to the effect of which he attributed the after immunity of his family from intermittent fevers.

The collection and preservation of flowers for medicinal purposes and distillation, will be found noticed under Vegetables.

Flowers, Artificial. The beauty and value of these pleasing articles of personal decoration mainly depend upon the taste and ingenuity of the maker. The delicate fingers of woman, and her ready powers of imitation and invention, combined with her natural affection for the chaste and beautiful, have enabled her the more especially to excel in this manufacture. The productions of the female artificial florists of the French capital are justly admired everywhere.

The French employ velvet, kid, and fine cambric for the petals, and taffeta for the leaves. Very recently thin plates of bleached whalebone have been used with great success for some portions of artificial flowers.

As colours and stains, the following are employed in Paris:—

Blue. Indigo dissolved in oil of vitriol, and the acid partly neutralised with salt of tartar or whiting.

Green. A solution of distilled verdigris.

Lilac. Liquid archil.

Red. Carmine dissolved in a solution of salt of tartar, or in spirits of hartshorn.

Violet. Liquid archil, mixed with a little salt of tartar.

Yellow. Tincture of turmeric.

The above colours are usually applied to the petals with the fingers.

Flowers. Syn. Flores, L. Among chemists, this term is applied to various pulverulent substances obtained by sublimation, as flowers of antimony, benzoin, zinc, sulphur, &c. The term has been discarded from modern chemical nomenclature, but is still commonly employed in familiar language and trade.

FLUID CAM′PHOR. Prep. (Sir J. Murray.) From camphor (in powder), 1 dr.; freshly precipitated carbonate of magnesia, 2 dr.; cold distilled water, 1 pint; the solution is effected by forcing in carbonic acid gas under pressure. Each fl. oz. contains 3 gr. of camphor, and 6 gr. of carbonate of magnesia. See Essence of Camphor.

FLUID MAGNE′SIA. Syn. Liquor Magnesiæ carbonatis, L. M. BICARBONATIS, L. The preparations sold under this name are mere solutions of freshly precipitated carbonate of magnesia in water, formed by means of carbonic acid gas, under powerful pressure, and long agitation. Those best known are Sir J. Murray’s and Mr Dinneford’s, each fl. oz. of which is said to contain about 17⁄2 gr. of the carbonate, but their actual richness in the latter seldom exceeds 10 or 12 gr., and by the time they reach the consumer is often as low as 5 or 6 gr. Recently precipitated carbonate of magnesia placed in a bottle or other suitable vessel, which is then filled by means of a soda-water apparatus with water fully charged with carbonic acid gas, readily dissolves on slight and cautious agitation, and the aërated water becomes saturated with magnesia. A scruple of carbonate of magnesia put into a soda-water bottle, and thus treated, is all taken up in from 20 minutes to half an hour, and the beverage continues beautifully clear.

FLUID-OZON (J. Krohn, Munich, with a certificate from Justus von Liebig). A mouth wash and toilet water. An aqueous solution of permanganate of soda, 1 in 9, contaminated with traces of sodium sulphate and chloride. (Wittstein.)

FLUM′MERY. A species of thick hasty-pudding made with oatmeal or rice, flavoured with milk, cream, almonds, orange flowers, lemons, &c., according to fancy.

Prep. 1. (Dutch flummery.) From blancmange and eggs, flavoured with lemon peel and sweetened with sugar.

2. (French flummery.) From equal parts of blancmange and cream, sweetened, and flavoured. The above are poured into forms, and served cold, to eat with wine, spirit, cider, &c.

3. (A. T. Thomson.) Take oatmeal or groats, 1 quart; rub it for a considerable time with hot water, 2 quarts; and let the mixture stand until it becomes sour; then add another quart of hot water, and strain through a hair sieve. Let stand till a white sediment is deposited, decant the fluid portion, and wash the sediment with cold water. This is now to be boiled with fresh water, until it forms a mucilage, stirring the whole time. A light and nutritious food, during early convalescence.

FLUOBORIC ACID. Syn. Borofluoric acid. This may be easily prepared by saturating hydrofluoric acid with boracic acid, keeping the mixture cool, and then concentrating it in platinum vessels till dense fumes arise.

FLUOHYDRIC ACID. See Fluoride of hydrogen.

FLU′ORIDE OF HYDROGEN. HF. Syn. Fluohydric acid; Hydrofluoric acid; A. hydrofluoricum, L. An acid composed of hydrogen and fluorine. It was discovered by Scheele, but was first obtained in a pure state by Gay-Lussac and Thénard, in 1810.

Prep. Pour concentrated sulphuric acid on half its weight of fluor spar, carefully separated from siliceous earth, and reduced to fine powder. The mixture must be made in a capacious leaden retort, and a gentle heat only applied, and the evolved gas must be collected in a leaden receiver, surrounded by ice.

Prop., &c. A colourless fluid below 59° Fahr., which speedily evaporates in dense white fumes when exposed to the air. Its affinity for water exceeds that of sulphuric acid, and its combination with that fluid is accompanied with a hissing noise, and a considerable increase of its sp. gr. up to a certain point. It attacks glass and silica, for which reason it cannot be preserved in glass vessels. Bottles of lead, silver, platinum, or pure gutta percha, are used to keep it in. It is highly corrosive, instantaneously destroying the skin on contact, and producing deep and serious ulcerations; its vapour is pungent, irritating, irrespirable, and poisonous. With the bases it unites to form FLUORIDES.

In the arts, hydrofluoric acid is used for etching on glass.

FLU′ORIDES. Compounds of fluorine with metals and other basic radicals. The fluorides of the metals are, with the exception of those of the alkaline metals, insoluble in water, while the fluorides of hydrogen, boron, and silicon, are gaseous, condensing at a low temperature to volatile liquids.

FLU′ORINE. F. Syn. Fluorinium, L. An element that has not yet been isolated, owing to its attacking and combining with every element or compound that at present has been exposed to it, except oxygen. It is presumably gaseous, and of a pale greenish-yellow colour.

FLU′OSILICIC ACID. Syn. Fluoride of silicon and hydrogen; Hydrofluosilic acid. Prep. From powdered fluor spar, and siliceous sand or powdered glass, of each 1 part; concentrated sulphuric acid, 2 parts: mix in a glass retort, apply a gentle heat, and pass the evolved gas into water through a layer of mercury. Decomposition ensues, silica being deposited in a gelatinous state, and hydrofluosilicic acid or fluosilic acid remains in solution. The acid liquor is used as a test for potassium and barium, with whose salts it yields nearly insoluble precipitates.

FLUX. Syn. Fluxus, Fluor, L. In medicine, a term formerly applied to several diseases attended with a copious discharge, as diarrhœa (FLUX), dysentery (BLOODY FLUX), English cholera (BILIOUS FLUX), fluor albus (WHITE FLUX), &c. These terms are still current among the vulgar.

Flux. In metallurgy, &c., a term applied to various substances of easy fusibility, which are added to others which are more refractory, to promote their fusion.

Prep. 1. (Black flux.) Nitre, 1 part; crude tartar or cream of tartar, 2 parts; mix, and deflagrate, by small quantities at a time, in a crucible, heated to dull redness. The product consists of carbonate of potassa, mixed with charcoal in a finely divided state. Used for smelting metallic ores. It exercises a reducing action, as well as promotes the fusion. It must be kept in a dry corked bottle.

2. (Christison’s flux.) Carbonate of soda (cryst.), 8 parts; charcoal (in fine powder), 1 part; heat the mixture gradually to redness. For reducing arsenic.

3. (Cornish reducing flux.) Crude tartar, 10 parts; nitre, 4 parts; borax, 3 parts; triturate together.

4. (Cornish refining flux, White flux.) Crude tartar and nitre, equal parts, deflagrated together. See Black Flux.

5. (Crude flux.) Same as BLACK FLUX, omitting the deflagration. Reducing.

6. (Fresenius’s flux.) Carbonate of potassa (dry), 3 parts; cyanide of potassium, 1 part. For the arsenical compounds.

7. (Liebig’s flux.) Carbonate of soda (dry) and cyanide of potassium, equal parts. As the last. See Arsenious Acid.

8. (Morveau’s reducing flux.) Powdered glass (free from lead), 8 parts; calcined borax and charcoal, of each, 1 part; all in fine powder, and triturated well together. Used as BLACK FLUX.

9. (White flux.) See above.

10. (Fluxes for enamels.) See Enamels.

11. (Various.) Borax, tartar, nitre, sal-ammoniac, common salt, limestone, glass, fluor spar, and several other substances, are used as fluxes in metallurgy.

Obs. On the large scale, crude tartar is employed in the preparation of fluxes; on the small scale, commercial cream of tartar or bitartrate of potassa.

FLY. The common house-fly (Musca domestica) causes considerable annoyance to the person in hot weather, as well as damage to handsome furniture, especially to picture frames, gilding, and the like. The best way to exterminate them is to expose on a plate one or other of the mixtures given under Fly Poison (below). The blow-fly (Musca vomitoria), and other insects, may be kept from attacking meat by dusting it over with black pepper, powdered ginger, or any other spice, or by skewering a piece of paper to it on which a drop or two of creasote has been poured. The spices may be readily washed off with water before dressing the meat.

It is a fact not generally known, that flies will not pass through a netting made of fine silk, thread, or wire, even though the meshes may be an inch apart, unless there is a window or light behind it. This affords us a ready means of excluding these insects from all our apartments which have windows only on one side of them, without keeping the latter closed. It is merely necessary to have an ornamental netting stretched across the opening, when, although flies may abound on the outside, none will venture into the room so protected. If, however, there is a window on the other side of the room, they will fly through the netting immediately. See below.

Fly-blow in Sheep. Oil of turpentine, 3 oz.; oil of amber, 1 oz.; corrosive sublimate, 1 dr. The sublimate must be first dissolved in a pint of whey, and then mixed with the oils.

Fly Papers. Those papers which, a few years ago, were sold about the streets of London by harsh-voiced cries of “Catch ′em alive-oh!” and which might be seen in many shop-windows covered with dead and dying flies, were prepared by rubbing factitious birdlime over sheets of paper. It would be difficult to conceive a more cruel or more offensive mode of catching flies than that of glueing their living bodies to an adhesive surface. A preferable kind of fly-paper is that called ‘PAPIER MOURE,’ which contains a large quantity of arsenic in its substance. This paper is kept wet when in use, and the flies, by sipping the moisture, are poisoned.

Fly Poison. Prep. 1. A strong solution of white arsenic (say 1 dr. to the pint), sweetened with moist sugar, treacle, or honey. Sold under the name of ‘Fly water,’

2. Treacle, honey, or moist sugar, mixed with about ⁄12th their weight of King’s yellow or orpiment.

Obs. Both the above are dangerous preparations, and should never be employed where there are children.

3. (Redwood.) Quassia chips (small), ⁄4 oz.; water, 1 pint; boil 10 minutes, strain, and add of treacle, 4 oz. “Flies will drink this with avidity, and are soon destroyed by it.”

4. Black pepper, 1 teaspoonful; brown sugar, 2 teaspoonfuls; cream, 4 teaspoonfuls. See below.

Fly Powder. The dark grey-coloured powder (so-called ‘sub-oxide’) obtained by the free exposure of metallic arsenic to the air. Mixed with sweets, it is used to kill flies.

Fly Water. See Fly Poison (above).

FOG. The influence of very intense foggy weather upon the death-rate is well illustrated by a reference to the Registrar-General’s returns for 1873. From the 8th to the 12th of December of that year an unprecedently thick fog prevailed in London. The mortality in the metropolis for the week ending December 6th was twenty-three persons per thousand; in the week following, during which the fog occurred, the death-rate rose to twenty-seven; and in the week after that, when the full effects of the fog could be estimated, the deaths were found to be thirty-eight in the thousand. In the same periods the deaths from phthisis and diseases of the respiratory organs were respectively 520, 764, and 1112. That this increased death-rate was not the result of the inclement weather by which the fog was accompanied is evidenced by the circumstance that in large provincial towns, where the weather was equally severe, but in which no fog occurred, the increase in the mortality, when compared to London, was slight.

The mean of the deaths registered in London, in the two weeks ending December 20th, showed an increase of 41 per cent. upon the number returned in the first week of the month; whilst during the same date the deaths in seventeen large English towns were only 8 per cent. This fatal fog occurred during the London cattle-show week, and killed a great number of the animals sent for exhibition.

In a specimen of the air of Manchester, obtained during the visitation of that city by a very dense fog, Dr Angus Smith discovered it contained a diminished amount of oxygen when compared with a favorable sample of air.

FOILS. These are thin leaves of polished metal, placed under precious stones and pastes, to heighten their brilliancy, or to vary the effect. Foils were formerly made of copper, tinned copper, tin, and silvered copper, but the last is the one wholly used for superior work at the present day.

Foils are of two descriptions:—white, for diamonds and mock diamonds, and—coloured, for the coloured gems. The latter are prepared by varnishing or lacquering the former. By their judicious use the colour of a stone may often be modified and improved. Thus, by placing a yellow foil under a green stone that turns too much on the blue, or a red one under a stone turning too much on the crimson, the hues will be brightened and enriched in proportion.

Prep. 1. (Crystal, Diamond, or White foil.)—a. This is made by coating a plate of copper with a layer of silver, and then rolling it into sheets in the flatting mill. The foil is then highly polished, or covered with crystal varnish.

b. The inside of the socket in which the stone or paste is to be set is covered with tin foil, by means of a little stiff gum or size; when dry, the surface is polished and the socket heated, and whilst it is warm, filled with quicksilver; after repose for two or three minutes the fluid metal is poured out, and the stone gently fitted in its place; lastly, the work is well fitted round the stone, to prevent the alloy being shaken out.

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 cassia and cloves. This method vastly increases the brilliancy both of real and factitious gems, and the work is very permanent.

2. (Coloured foils.) The following formulæ 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 shell-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 shell-lac varnish.

f. (Green.)—α. From pale shell-lac, dissolved in alcohol (lacquer), and tinged green by dissolving verdigris or acetate of copper in it.

β. From sesquiferrocyanide of iron and bichromate of potassa, of each ⁄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 mass becomes homogeneous 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.)—α. From lake or carmine, ground in isinglass.

β. Lake ground in shell-lac varnish. Both are used when the colour turns on the purple.

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

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

β. 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 isinglass 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 glass or paste; and by applying them to foils set under coloured pastes (FACTITIOUS 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 quantities, 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 quantity 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 coarseness of the flannel is not a matter of indifference. The coarser 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 quantity of liquid forming a fomentation, as well as the size of the cloths employed, must entirely depend upon circumstances. 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 ⁄2 pint to a pint of liquid may be found a sufficient quantity; whilst in others several quarts will be required. Under all circumstances, 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 formulæ 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), 1⁄2 oz.; water, 3⁄2 pints; boil to 2⁄2 pints; add of elder flowers, ⁄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 ⁄4 pint, add pyroligneous acid, 2 fl. oz.; boil for 10 minutes longer, then further add of sherry wine, ⁄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 potassium, 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 arnicæ, 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, ⁄2 oz.; boiling vinegar, q. s. to strain 6 fl. oz. of infusion, in which dissolve of carbonate of ammonia, 2 dr. Used in œdema of the scrotum.

Fomentation, Aromat′ic. Syn. Fomentatio aromatica, Fotus aromaticus, L. Prep. 1. Sea wormwood, southernwood, and chamomiles, of each 1 oz.; laurel leaves, ⁄2 oz.; water 5 pints; boil to half gall., and strain. In rheumatism, cutaneous affections, colic, &c.

2. (Augustin.) Rosemary, ⁄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, 2⁄2 pints; digest 1 hour, and strain.

4. (Ricord.) Tannin, 2⁄2 dr.; aromatic wine (hot), ⁄2 pint; dissolve.

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

Fomentation of Belladon′na. Syn. Fotus belladonnæ, 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 dulcamaræ, L. Prep. Bitter-sweet stalks, 10 dr.; water, 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.

Fomentation, Com′mon. Syn. Fotus communis. (L. 1744.) Prep. Dried southernwood, sea wormwood, chamomile, of each 1 oz.; dried bay leaves, ⁄2 oz.; water, 5 pints; boil slightly, and strain.

Fomentation, Compound of Hemlock. (Guy’s Hosp.) Syn. Fomentum conii compositum. Prep. Dried hemlock, 2 oz.; dried chamomiles, ⁄2 oz.; boiling water, 1⁄2 pint; macerate for 2 hours, strain, and press.

Fomentation, Diuret′ic. Syn. Fomentatio diuretica, L. Prep. (Trousseau.) Tinctures of squills and foxglove, of each 2 oz.; hot water, 6 fluid oz.; mix. Applied by lint or linen compresses to the insides of the thighs, in dropsies, when the stomach will not bear diuretics.

Fomentation of El′der Flowers. Syn. Fotus sambuci, L. Prep. From elder flowers, 1 oz.; boiling water, 2 quarts; digest in a hot place for 1 hour, and express the liquor. Emollient.

Fomentation, Emol′lient. Syn. Fomentatio emolliens. L. Prep. 1. Marshmallow root and poppy heads, of each 1 oz.; water, 3 pints; boil to a quart, and strain.

2. (P. Cod.) Emollient herbs, 1 oz.; boiling water, 1 quart; infuse 1 hour, and strain with expression. (See above.)

Fomentation, Foxglove. Syn. Fomentum digitalis. Dried foxglove, 1 oz.; boiling water, 1⁄2 pint; infuse, and strain.

Fomentation of Galls. Syn Fomentum gallæ. Prep. Bruised galls, ⁄2 oz.; boiling water, 2 lbs.; macerate for an hour and strain.

Fomentation, Narcot′ic. Syn. Fomentatio narcotica, L. Prep. (P. Cod.) Narcotic herbs, 1 oz.; boiling water, 1⁄2 pint; infuse as last.

Fomentation, Poppy. Syn. Fomentum papaveris. As Decoction of Poppies.

Fomentation, Resol′vent. Syn. Fotus resolvens, L. Prep. (Richard.) Fomentation of elder flowers, 8 fl. oz.; liquor of diacetate of lead, ⁄2 fl. dr.; mix. Used to discuss tumours, &c.

Fomentation, Stim′ulant. Syn. Fomentatio stimulans, L. Prep. 1. Sesquicarbonate of ammonia, 1 oz.; tincture of cantharides, 2 fl. oz.; warm water, 1 pint.

2. Household mustard, 4 oz.; hot water, 1⁄2 pint; mix. Both the above are rubefacient and counter-irritant, and excellent in rheumatism, neuralgia, &c.

Fomentation, Tannin. Syn. Fomentum tannini. (Ricord.) Prep. Tannin, 2 dr.; aromatic wine, 8 oz.

Fomentation, Ver′mifuge. Syn. Fomentatio vermifuga, Fotus anthelminticus, L. Prep. Leaves and flowers of tansy, wormwood, and chamomile, of each 3 oz.; water, 1 quart; boil to 1⁄2 pint, and strain. Applied to the abdomen, &c., in worms.

Fomentation, Wine. Syn. Fotus vinosus (Par. Cod.) Prep. Red wine, 2 pints; honey 4 oz.

FOOD. Syn. Cibus, Materia alimentaria, L. Anything which feeds or promotes the natural growth of organic bodies, by supplying them with materials which, by assimilation, may be converted into the substances of which they are composed; or which, by its decomposition or slow combustion, maintains the temperature, or some other essential condition of life, at the proper standard. The numerous articles employed as food are all compounds; and in many cases they consist of mechanical mixtures or chemical combinations of two or more compounds. Organized matter, or that which has possessed either animal or vegetable life, or which has been produced by living organs, seems to be alone capable of assimilation, to any extent, by the animal system; and hence it is from the organic kingdom that our aliments are necessarily derived. Water, iron, earthy phosphates, chloride of sodium, and other salts, which form the inorganic constituents of the body, though not of themselves nourishing, are also assimilated when taken in conjunction with organic aliments, and then contribute essentially to nutrition. In the animal and vegetable substances employed as food, these inorganic compounds are provided in small but sufficient quantities to meet the requirements of the healthy body, and in this state of combination alone can they be regarded in the light of aliments. A complete consideration of this subject embraces, not only all the substances used as food, but also those things which when taken with them improve their flavour, promote their digestion, and render them more wholesome and nutritive; and also their preparation for the table in its various relations with health and disease.

The following ‘BILLS OF FARE,’ for which we are indebted chiefly to Soyer, Rundell, and others, exhibit the various articles in season at different periods of the year.

First quarter. January.—Poultry and game: Pheasants, partridges, hares, rabbits, woodcocks, snipes, turkeys, capons, pullets, fowls, chickens, and tame pigeons.—Fish: Carp, tench, perch, lampreys, eels, cray-fish, cod, soles, flounders, plaice, turbot, thornback, skate, sturgeon, smelts, whitings, lobsters, crabs, prawns, and oysters.—Vegetables: Cabbage, savoys, colewort, sprouts, leeks, onions, beet, sorrel, chervil, endive, spinach, celery, garlic, scorzonera, potatoes, parsnips, turnips, brocoli (white and purple), shalots, lettuces, cresses, mustard, rape, salsafy, and herbs of all sorts (some dry and some green); cucumbers, asparagus, and mushrooms are also to be had, though not in season.—Fruit: Apples, pears, nuts, walnuts, medlars, and grapes.

February and March.—Meat, fowls, and game, as in January, with the addition of ducklings and chickens.—Fish: As the last two months (cod is not thought so good from February to July, although it is still sold at the fishmonger’s).—Vegetables: The same as the previous months, with the addition of kidney-beans.—Fruit: Apples, pears, and forced strawberries.

Second quarter. April, May, and June.—Meat: Beef, mutton, veal, lamb, and venison (in June).—Poultry: Pullets, fowls, chickens, ducklings, pigeons, rabbits, and leverets.—Fish: Carp, tench, soles, smelts, eels, trout, turbot, lobsters, chub, salmon, herrings, cray-fish, mackerel, crabs, prawns, and shrimps.—Vegetables: As before; and in May, early potatoes and cabbages, peas, radishes, kidney-beans, carrots, turnips, cauliflowers, asparagus, artichokes, and numerous salads (forced).—Fruit: (in June) strawberries, cherries, melons, green apricots, and currants and gooseberries for tarts; pears, grapes, nectarines, peaches, and some other fruit.

Third quarter. July, August, and September.—Meat, as before.—Poultry, &c.: Pullets, fowls, chickens, rabbits, pigeons, green geese, leverets, and turkey poults. Two former months, plovers and wheat-ears (in September), partridges, geese, &c.—Fish: Cod, haddocks, flounders, plaice, skate, thornback, mullets, pike, carp, eels, shellfish (except oysters), and mackerel (during the first two months of the quarter, but they are not good in August).—Vegetables: Of all sorts, beans, peas, French beans, &c.—Fruit: (In July)—Strawberries, gooseberries, pine-apples, plums (various), cherries, apricots, raspberries, melons, currants, and damsons. (In August and September)—Peaches, plums, figs, filberts, mulberries, cherries, apples, pears, nectarines, and grapes. (During the latter months)—Pines, melons, strawberries, medlars, and quinces. (In September)—Morella cherries, damsons, and various plums.

Fourth quarter. October, November, and December.—Meat, as before, and doe venison.—Poultry and Game: Domestic fowls, as in first quarter; pheasants (from the 1st of October); partridges, larks, hares, dotterels (at the end of the month), wild-ducks, teal, snipes, widgeon, and grouse.—Fish: Dories, smelts, pike, perch, halibuts, brills, carp, salmon-trout, barbel, gudgeons, tench, and shellfish.—Vegetables: (As in January), French-beans, last crops of beans, &c.—Fruit: Peaches, pears, figs, bullace, grapes, apples, medlars, damsons, filberts, walnuts, nuts, quinces, services, and medlars. (In November)—Meat, &c.: Beef, mutton, veal, pork, house-lamb, doe venison, and poultry and game as in the last month.—Fish: As the last month.—Vegetables: Carrots, turnips, parsnips, potatoes, skirrets, scorzonera, onions, leeks, shalots, cabbage, savoys, colewort, spinach, chardbeats, chardoons, cresses, endive, celery, lettuces, salad-herbs, and various pot-herbs.—Fruit: Pears, apples, nuts, walnuts, bullace, chestnuts, medlars, and grapes. (In December)—Meat, &c.: Beef, mutton, veal, house-lamb, pork, and venison.—Poultry and Game: Geese, turkeys, pullets, pigeons, capons, fowls, chickens, rabbits, hares, snipes, woodcocks, larks, pheasants, partridges, sea-fowls, guinea-fowls, wild ducks, teal, widgeon, dotterels, dun-birds, and grouse.—Fish: Cod, turbot, halibuts, soles, gurnets, sturgeon, carp, gudgeons, codlings, eels, dories, and shell-fish.—Vegetables: As in last month. Asparagus, &c., forced.—Fruit: As before, except bullace.

Food, Inspection of. The Public Health Act enacts that—

“Any medical officer of health or inspector of nuisances may at all reasonable times, inspect and examine any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk exposed for sale, or deposited in any place for the purpose of sale, or of preparation for sale, and intended for the food of man, the proof that the same was not exposed or deposited for any such purpose, or was not intended for the food of man, resting with the party charged; and if any such animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk, appears to such medical officer or inspector to be diseased, or unsound, or unwholesome, or unfit for the food of man, he may seize and carry away the same himself or by an assistant, in order to have the same dealt with by a justice.” (P. H., s. 116.)

“If it appears to the justice that any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk so seized is diseased, or unsound, or unwholesome, or unfit for the food of man, he shall condemn the same and order it to be destroyed, or so disposed of, as to prevent it from being exposed for sale, or used for such food; and the person to whom the same belongs or did belong at the time of sale, or of exposure for sale, or in whose possession, or on whose premises the same was found, shall be liable to a penalty not exceeding £20 for every animal, carcase, or fish, or piece of meat, flesh, or fish, or any poultry or game, or for the parcel of fruit, vegetables, corn, bread, or flour, or for the milk so condemned, or at the discretion of the justice, without the infliction of a fine, to imprisonment for a term of not more than three months.

“The justice who, under this section, is empowered to convict the offender, may be either the justice who may have ordered the article to be disposed of or destroyed, or any other justice having jurisdiction in the place.” (P. H., s. 117.)

“Any person who in any manner prevents any medical officer of health or inspector of nuisances from entering any premises and inspecting any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk exposed or deposited for the purpose of sale, or of preparation for sale, and intended for the food of man, or who obstructs or impedes any such officer or inspector, or his assistant, when carrying into execution the provisions of this Act, shall be liable to a penalty, not exceeding £5.” (P. H., s. 118.)

“Any complaint made on oath, by a medical officer of health, or by an inspector, or other officer of a local authority, any justice may grant a warrant to any such officer, to enter any building, or part of a building in which any such officer has reason for believing that there is kept or concealed any animal, carcase, meat, poultry, game, flesh, fish, fruit, vegetables, corn, bread, flour, or milk which is intended for sale for the food of man, and is diseased, unsound or unwholesome, or unfit for the food of man and to search for, seize, and carry away any such animal, or other article, in order to have the same dealt with by a justice under the provisions of this Act.

Any person who obstructs any such officer in the performance of his duty, under such warrant shall, in addition to any other punishment to which he may be subject, be liable to a penalty not exceeding £20.” (P. H., s. 119.)

FOOL. Cooks give this name to a species of jam made of boiled and crushed fruit, mixed with milk or cream, and sweetened.

Fool, Ap′ple. From the peeled and cored fruit, placed in a jar, with moist sugar, q. s. to render it palatable, and a very little cider or perry; the jar is set in a saucepan of water over the fire, and the heat continued until the apples become quite soft, when they are pulped through a colander, and a sufficient quantity of milk, a little cream, and some sugar, added to bring them to the proper ‘palate.’

Fool, Goose′berry. From gooseberries, as the last. Those which are unripe are generally preferred. These preparations, when nicely made, are very pleasant and wholesome.

FOOT (Human). See Feet.

FOOTS. Coarse moist sugar. The scrapings of the sugar hogsheads, refuse sugar, waste, and dirt, is also sold to the publicans under this name, who use it in the adulteration of their beer; chiefly to make it stand more water, and to impart ‘briskness.’

FORCE′MEAT. Syn. Farce, Stuffing. A species of sausage meat, either served up alone, or employed as an ingredient in other dishes.

Mrs Rundell truly remarks that “at many tables, where everything else is done well, it is common to find very bad forcemeat or stuffing.” To avoid this error, care should be taken to so proportion the ingredients that “no one flavour should predominate; yet if several dishes be served the same day, there should be a marked variety in the tastes of the forcemeats as well as of the gravies. A general fault is, that the tastes of lemon peel and thyme overcome all others; therefore they should only be used in small quantities.” Forcemeats should be just consistent enough to cut with a knife, but not dry and heavy. Herbs are very essential ingredients; and it is the copious and judicious use of them that chiefly gives the cookery of the French its superior flavour. “To force fowls, meat, &c., is to stuff them.” (Mrs Rundell.)

FOR′CING. Horticulturists apply this term to the art of accelerating the growth of plants, so as to obtain fruits or flowers at unusual seasons. Dung-beds, bark-beds, and frames, pits, and houses, with glass roofs, are commonly employed by the gardeners for this purpose.

FORGERIES, PROTECTION FROM. See Paper, Protective.

FORMATE. Syn. Formiate. Salts, in which one atom of hydrogen in formic acid is replaced by a metal or other basic radical. They are best obtained either by direct saturation of the acid, or by double decomposition; most of them are very soluble, and are decomposed by hot oil of vitriol. Formate of ammonium crystallises in square prisms; formate of sodium, in rhombic prisms; formate of potassium is deliquescent, and crystallises with difficulty; the formates of barium, calcium, magnesium, and strontium, form small prismatic crystals; formate of lead assumes the shape of small colourless needles, soluble in 40 parts of water; the formates of cobalt, iron, manganese, nickel, and zinc, are easily crystallisable, whilst that of copper forms very beautiful, large, bright-blue rhombic prisms; formate of silver is less soluble than the salt of lead, and is decomposed at a gentle heat.

FORMIC ACID. HCHO2. Syn. Hydrogen Formiate. An organic acid, obtained by oxidizing many organic substances, and found in the red ant.

Prep. Sugar, 1 part; water, 2 parts; binoxide of manganese, 3 parts; mix in a retort capable of holding fully 10 times the bulk of the ingredients, and add, cautiously, oil of vitriol, 3 parts, diluted with an equal weight of water; as soon as the first violent effervescence has subsided, heat may be applied, and the product collected and purified, as below.

Formate of lead in fine powder is introduced into a long glass tube, one end of which is connected with an apparatus evolving sulphuretted hydrogen, and the other with a receiver. As soon as the salt is entirely decomposed (blackened) a very gentle heat is applied, and the distilled liquid collected; the product is, lastly, boiled for a minute or less, to expel any adhering sulphuretted gas. This furnishes chemically pure formic acid.

From wood spirit, 1 part; bichromate of potassium and sulphuric acid, of each 3 parts; the sulphuric acid, diluted with an equal weight of water, being gradually added last. A portion of wood spirit distils over with the acid, and may be again treated with bichromate of potassium and sulphuric acid, when a fresh portion of formic acid will be produced. This process yields a large product.

Prop., purific., &c. The products of the above processes are limpid and colourless; the stronger ones fume slightly in the air, and possess an extremely penetrating odour. The acid obtained by the second process boils at 209° Fahr., crystallises in brilliant scales below 32°, and has the sp. gr. 1·2353. Its vapour is inflammable, and burns with a blue flame. It is extremely corrosive, and rapidly destroys the texture of living organic substances. The products of the other processes are very dilute, and possess the above properties in only a minor degree. They may all be purified and concentrated by saturating them with pure carbonate of sodium or of potassium, and after subjecting the liquid to a gentle heat for a short time, and liberating the formic acid from the salt by means of dilute sulphuric acid, finally submitting the mixture to distillation, when the hydrated acid will come over perfectly pure.

Formic acid reduces the salts of mercury and silver, and forms salts with the bases termed formiates.

Formic acid is readily distinguished from acetic acid, which in many points it resembles, by heating it with a little solution of oxide of silver or mercury; the metal is reduced, and precipitated in a pulverulent state, while carbonic acid is extricated. The odours of the two acids also vary.

FORMICA. Syn. The Ant. The following are the principal species of the genus Formica. F. flava, the yellow ant. Many careful observers say this species keeps in its nest the Aphis radicans, which when its abdomen is touched by the ant, excretes a saccharine substance on which the ants feed. F. rufa, or large red ant, F. fusca; or brown ant, Polyergus rufescens, and F. sanguinea. These two latter are sometimes called amazon ants, from their pugilistic propensities. They have been known to make regular raids against other species of ants, and to carry off their larvæ and pupæ to their own nests, where they rear the insects that come of them, and afterwards employ them as slaves, causing them to excavate passages, to collect food, to carry larvæ and (so dependent do the masters become on the exertions of their bondsman) even to feed them; it being a well-attested fact that the slave holders would starve if left to themselves. See Ant.

FORMOBENZOIC ACID. (HC7H6O,CHO2). Syn. Formiate of Hydride of Benzoyle. Mandelic acid. When the distilled water of bitter almonds (containing hydrocyanic acid and the essential oil) is boiled with hydrochloric acid, a curious reaction occurs; the hydrocyanic acid is decomposed—into ammonia which unites with the hydrochloric acid, and formic acid which enters into combination with the oil of almonds—producing a new body possessed of acid properties, and termed Formobenzoic acid. On evaporating the solution the acid may be obtained in mixture with ammonia hydrochlorate, from which it may be separated by ether; the ethereal solution deposits it in rhomboidal tables. It has a sour taste and is easily soluble in alcohol. When heated it fuses at a low temperature, emitting an agreeable odour of hawthorn blossoms. (Miller.)

FORM′ULA. [L.] In pharmacy and medicine, a short form of prescription; a recipe. By chemists the term is applied to a grouping of symbols, expressing the composition of a body; thus, HCl (standing for 1 atom of hydrogen united to 1 atom of chlorine) is the formula for hydrochloric acid. A chemical formula is termed empirical when it merely gives the simplest possible expression of the composition of the substance to which it refers. A rational formula, on the contrary, aims at describing the exact composition of molecule, or combining weight of the substance, but stating the absolute number of atoms of such of the elements essential to that object, as well as the mere relations existing between them. The empirical formula is at once deduced from the analysis of the substance, reckoned to 100 parts; the rational formula requires, in addition, a knowledge of its combining quantity, which can only be obtained by direct experiment, by synthesis, or by the careful examination of one or more of its most definite compounds. Thus, the composition of acetic acid is expressed by the formula CH2O, which exhibits the simplest relations of the three elements; if we want to express the quantities of these, in atoms required to make up one molecule of acetic acid, we have to adopt the formula C2H4O2 or HC2H3O2.

FOR′MYL. Syn. Formyle. A hypothetical organic radical, having the composition C2H. Its existence was inferred from the constitution of certain organic compounds which are now referred to the methyl-series. Formic acid was supposed to be an oxide of formyl; and chloroform, the terchloride of formyl.