Chapter LXXXIV: Part 2 (45)

In this latter case the balance of nature is interfered with, and the system of checks which she has established for the prevention of the undue preponderance of one tribe of the animal kingdom over the other being interfered with, the result will be the undue propagation of particular species inimical to the operations of the husbandman, &c.

As illustrating this, we may mention the destruction to various crops in France caused some years ago by the ravages of certain grubs and insects, the unusual increase in the numbers of which was clearly traced to the foolish practice, amongst French farmers, of shooting all the small birds. See BUG, LOUSE, RATS.

=VERT′IGO.= Dizziness and swimming of the head. In its more serious forms there is more or less mental confusion, the objects around the patient appear in motion, the ears are oppressed with strange sounds, and visible illusions are experienced, whether the eyes be closed or open, and in darkness as well as in the light. The causes are fulness of the vessels of the head, nervous derangement, general debility, hæmorrhage, the use of narcotics, an overloaded stomach, and, in some cases, an empty one. It is also frequently symptomatic of fevers and inflammations, and of a condition threatening apoplexy. The treatment must be varied, according to the cause and the peculiar habit or condition of the patient.

=VES′ICANTS.= _Syn._ EPISPASTICS; EPISPASTICA, VESICANTIA, L. Substances which vesicate or raise blisters. Among these are the cantharis or blistering fly, mezereon, croton oil, boiling water, &c.; the first only of which is now in common use in England.

“It is a principle sufficiently established with regard to the living system, that, where a morbid action exists, it may often be removed by inducing an action of a different kind, in the same or a neighbouring part. On this principle is explained the utility of blisters in local inflammation and spasmodic action, and it regulates their application in pneumonia, gastritis, hepatitis, phrenitis, angina, rheumatism, colic, and spasmodic affections of the stomach——diseases in which they are employed with the most marked advantage. A similar principle exists with respect to pain; exciting one pain often relieves another. Hence blisters often give relief in toothache, and some other painful affections. Lastly, blisters, by their operation, communicate a stimulus to the whole system, and raise the vigour of the circulation. Hence, in part, their utility in fevers of the typhoid kind, though in such cases they are used with still more advantage to obviate or remove local inflammation.” (‘Med. Lex.’)

Blisters are commonly prepared with cantharides plaster, or with some other preparation of cantharides; and, in the former case, are usually lightly covered with the powdered fly. In order to prevent the action of the cantharides upon the mucous membrane of the bladder, blistering plasters are often sprinkled with a little powdered camphor, or, better still, are moistened with camphorated ether, which leaves a thin layer of camphor. In all these cases the layer should not be too thick, for in that case the plaster would not take effect.

When it is not wished to maintain a discharge from the blistered part, it is sufficient to make a puncture in the vesicle, to let out the fluid; but when the case requires the blister to be ‘kept open,’ as it is called, the whole of the detached cuticle is carefully removed with a pair of scissors, and the part is dressed with either the ointment of cantharides or of savine, at first more or less diluted with lard, or simple ointment, with an occasional dressing of resin cerate. According to Mr Crowther, the blistered surface is best kept clean by daily fomentation with warm water.

Of late years, to obviate the unpleasant effects occasionally arising from the common blister, various compounds having cantharides for their base have been brought before the public. Of these, the vesicating collodion noticed under COLLODION is the most convenient and effective. The following also deserve notice:——

1. Take of cantharides, in fine powder, 2 parts; spermaceti, 2 parts; olive oil, 4 parts; white wax, 8 parts; water, 10 parts; simmer, with constant agitation, for 2 hours, strain through flannel, separate the plaster from the water, gently remelt it with common turpentine, 1 part, and spread the mass whilst still fluid. This nearly resembles the form recommended by MM. Henry and Guibourt.

2. (P. Cod.) Distil off the ether from a concentrated ethereal tincture of cantharides, melt the oily residue with twice its weight of white wax, and spread the mixture on thin oiled silk, or on cloth, prepared with wax plaster.

3. (Oettinger.) Cantharidal ether (prepared from cantharides, l part; ether 2 parts), and sulphuric ether, of each 10 dr.; turpentine and black resin, of each 2-1/2 dr.; mix, dissolve, and apply it to the surface of stretched silk or taffeta which has been previously prepared with two coatings of a solution of isinglass.

4. (CHARTA EPISPASTICA, B. P.). Digest 4 oz. of white wax, 1-1/2 oz. spermaceti, 2 oz. fluid of olive oil, 3 oz. of resin, 1 oz. of cantharides in powder, and distilled water 6 oz., in a water bath for two hours, stirring constantly, strain, and separate the plaster from the watery liquid. Mix 1/4 oz. fl. of Canada balsam with the plaster, melted in a shallow vessel, and pass strips of paper over the hot liquid, so that one surface of the paper shall receive a thin coating of plaster. It may be convenient to employ paper, ruled in square inches.

5. (CHARTA SINAPIS, B. P.) Black mustard seeds, in powder, 1 oz.; solution of gutta percha, 2 oz., or q. s. Mix so as to make a semi-fluid, and having poured this into a shallow flat-bottom vessel, such as a dinner plate, pass strips of cartridge paper ever its surface, so that one side of the paper shall receive a thin coating of the mixture. Then lay the paper on a table, with the coated side upwards, and let it remain exposed to the air until the coating has hardened. Before being applied let the mustard paper be immersed for a few seconds in tepid water.

6. (VESICATING SPARADRAP, P. Cod.) Gum elini, 1 oz.; olive oil, 1/2 oz.; basilicon ointment, 2-1/4 oz.; resin, 1 oz.; yellow wax, 3-3/4 oz.; cantharides, in fine powder, 4-1/4 oz. Melt the first five substances together, and stir in the cantharides; when sufficiently cold, and well mixed, spread on waxed strips of linen.

_Obs._ The above compounds are spread on leather, linen, paper, silk, oiled silk, taffeta, &c., and then form the numerous compounds vended under the names of——blistering tissue, rannus vesicatorius, papier epispastique, sparadrapum vesicatorium, taffetas vesicans, tela vesicatoria, &c.

Acetic extract of cantharides, croton oil, or extract of mezereon, is sometimes substituted for the ethereal extract ordered in the above formulæ.

The ‘papier epispastique’ of Vée is prepared of three strengths, which are respectively distinguished by the colours white, green, and red. The composition is made by boiling powdered cantharides for an hour with water, lard, and green ointment, or with lard coloured with alkanet root, adding white wax to the strained fats, and spreading the mixture whilst fluid:——No. 1 is made with 10 oz. of cantharides to 4 lbs. of lard; No. 2 of 1 lb. of cantharides to 8 lbs. of green ointment; and No. 3, of 1-1/2 lb. of flies to 8 lbs. of reddened lard. To each are added 2 lbs. of white wax. (Dorvault.)

The magistral blister of Valleix is a revival of the vesicating epithem. See BLISTER, CANTHARIDES, COLLODION, &c., and _below_.

=VESICA′TION.= The formation of a blister is a vital process, and its success may be taken as a proof of the presence of life. Hence a French physician, Dr Mandl, has suggested such a stimulation of the skin as would ordinarily cause a blister as a test of life, in those cases of long-continued trance which we occasionally hear of, where all the functions of life seem to be extinct. Dr Mandl’s plan is to apply a stick of lunar caustic. The application of a little strong vinegar of cantharides, or other cantharidal blister, of the size of a sixpenny piece, or of two or three spoonfuls of boiling water by means of a bent tube of like diameter, is however, more certain and satisfactory.

=VESICA′TORIN.= _Syn._ CANTHARIDIN, CANTHARIDINA, CANTHARIDES CAMPHOR. The blistering principle of Spanish flies, discovered by M. Robiquet.

_Prep._ 1. (P. Cod.) Exhaust powdered cantharides with concentrated alcohol by percolation; distil off the spirit from the filtered tincture, and leave the residuum to deposit crystals; these may be purified by dissolving them in boiling alcohol, digestion with animal charcoal, filtration whilst hot, and crystallising by refrigeration.

2. (Thierry.) Macerate cantharides (in coarse powder) for several days in ether, in a closed displacement apparatus; then, after the whole of the soluble matter has been extracted by the addition of fresh portions of ether, pour on sufficient water to displace the retained ether; next distil off the ether, dissolve the remaining extract in boiling alcohol, filter while hot, and abandon the filtrate to spontaneous evaporation. _Prod._ ·5%.

3. Digest the aqueous extract of cantharides in hot alcohol, filter, evaporate to dryness, digest the residuum in sulphuric ether, evaporate, and slightly wash the resulting crystals with cold alcohol.

_Prop., &c._ Micaceous plates resembling spermaceti; fusible; vaporisable; insoluble in water; soluble in ether, oils, acetic acid, and hot alcohol; powerfully vesicant and poisonous. Its vapour, even at ordinary temperatures, frequently produces temporary blindness. The 1-100th part of a grain, placed on a piece of paper, and applied to the edge of the lower lip, caused small blisters in 15 minutes, which, when rubbed with a little simple cerate, extended over a large surface, and covered both lips with blisters. (Robiquet.)

=VETCH.= The common name of various leguminous plants of the genera _Vicia_ and _Ervum_, now much cultivated as green fodder for milch cows and working stock. The seeds (tares) were formerly reputed detersive and astringent. Those of “the Canadian variety make good bread.” (Lindley.)

=VET′ERINARY MEDICINES.= The common form of medicine for horses is that popularly known as horse balls. They are usually prepared by mixing the dry ingredients, in the state of powder, with a sufficient quantity of treacle, or syrup bottoms, to give the mass a proper consistence for rolling into balls; adding, when necessary, linseed meal, or any other simple powder, to increase the bulk. The usual practice among the veterinary druggists is to keep a compound known in the trade as ‘ball-mass,’ or ‘common mass,’ ready prepared to give form and bulk to more active ingredients. This is usually made of about equal parts of linseed meal and treacle, together with a little palm or lard, thoroughly incorporated by kneading with the hands; and it is kept in a cool situation, tied over to prevent it drying and hardening. For use, the ball-masses are either rolled or moulded into small cylinders of about 1-1/2 to 1-3/4 oz. in weight; and in size, from 2 to 2-3/4 inches long, and from about 1/2 to 7/8 of an inch in diameter; and they are wrapped in soft paper, which is administered with them. Those for dogs are commonly formed into large boluses or nut-like pieces. The common practice in some houses of adding a little salt of tartar or acetate of potassa to ball-masses kept in stock, for the purpose of preserving them in a soft state, is not to be commended, since these articles decompose many of the saline and mineral compounds which are subsequently added to them.

Medicines for neat cattle are always administered in a liquid form, popularly called drenches. A similar plan is adopted with small cattle, as sheep and goats. For these, however, the quantity should seldom exceed 1/4 pint. In all cases, drenches should be very slowly administered.

The following are a few useful horse-balls:

=Alterative Balls.=——1. Levigated sulphide of antimony, sulphur, and linseed meal, of each 3 oz.; nitre, 4 oz.; palm oil, q. s. to form a mass; for 12 balls. One to be taken every day, or every other day.

2. (Bell.) Sulphide of antimony, nitre, sulphur, and Æthiops mineral, of each 3 oz.; soft soap, 10 oz.; oil of juniper, 1/2 oz.; for 12 balls. As the last.

3. (White.) Sulphide of antimony, caraways, and treacle, of each 1/4 oz.; for one ball. As the last.

CORDIAL BALLS.——1. (Blaine). Coriander seed, caraway, and gentian, of each 8 oz.; ginger, 4 oz.; oil of aniseed, 1/2 oz.; honey or palm oil, q. s. to form a mass. Cordial, warming, and stomachic.——_Dose_, 1-1/2 oz.

2. (Hill.) Anise, caraway, and cumin seed, of each 4 lbs.; ginger, 2 lbs.; treacle, q. s.; divide into 1-3/4 oz. balls. _Prod._ 21 lbs.

COUGH BALLS.——1. (Blaine.) Ipecacuanha, 1 dr.; camphor 2 dr.; honey, q. s. to form a ball. One night and morning.

2. (B. Clark.) Emetic tartar and benzoin, of each 2 dr.; squills, 4 dr.; spermaceti and balsam of copaiba, of each 1 oz.; elecampane and sulphur, of each 2 oz.; syrup of poppies, q. s. to mix; for 8 balls. As the last.

DIURETIC BALLS.——1. (Bracy Clark.) Nitre and common turpentine, of each 1 lb.; Castile soap, 1/2 lb.; barley meal, 2-1/2 lbs., or q. s. For common-sized balls.

2. (Morton.) Digitalis 1 oz.; aloes, 2 oz.; liquorice, 13 oz.; honey or Barbadoes tar, q. s. to mix; for 1-oz. balls. One, twice a day with care.

PHYSIC BALLS, PURGING B., CATHARTIC B.——1. Aloes and hard soap, of each 5 oz.; salt of tartar and cayenne pepper, of each 1 oz.; melt together. For 8 balls.

2. (Vet. Coll.)——_a._ (Common physic ball.) Aloes, 8 oz.; treacle, 3 oz.; olive oil, 1 oz.; melted together.——_Dose_, 1 to 1-1/2 oz.

_b._ (Stronger ball.) To each dose of the last, add of croton oil, 4 to 8 drops.

=Obs.= The _dose_ of the above is 1 ball, fasting in the morning, preceded by a bran mash, on one or two successive nights, and followed by gentle exercise until the ball begins to operate.

WORM BALLS.——1. Barbadoes aloes, 5 dr.; calomel and ginger, of each 2 dr.; oil of cloves, 12 drops; treacle, q. s. for a ball.

2. (J. Bell & Co.) Barbadoes aloes, 5 to 8 dr.; powdered tin,Æthiops mineral, and ginger, of each 2 dr.; oils of aniseed and savine, of each 20 drops; treacle, q. s. for a ball.

3. (Clater.) Sulphur and emetic tartar, of each 1 dr.; linseed meal, 4 dr.; palm oil, q. s. to form a ball. One every morning, having prepared the animal with a physic ball containing 1 dr. of calomel. See BALLS; also Tuson’s ‘Veterinary Pharmacopœia.’

=VIN′EGAR.= _Syn._ ACETUM, L.; VINAIGRE, Fr. Dilute acetic acid, more or less contaminated with gum, sugar and vegetable matter.

1. MALT VINEGAR; ACETUM, BRITISH VINEGAr (B. P.); ACETUM BRITTANNICUM (Ph. L. & E.), L. This is the ordinary coloured vinegar consumed in this country, and is correctly described in the Ph. L. as “impure (dilute) acetic acid, prepared by fermentation from an infusion of malt (malt-wort).”

In the manufacture of MALT VINEGAR a mixture of malt and barley is mashed with hot water, and the resulting wort fermented, as in the common process of brewing. The liquor is then run into barrels, placed endways, tied over with coarse canvas, and arranged side by side in darkened chambers, moderately heated by a stove, and freely supplied with air. Here it remains till the acetous fermentation is nearly complete, which usually occupies several weeks, or even months. The newly formed vinegar is next run off into two large tuns, furnished with false bottoms, on which some ‘rape’ (the pressed cake from making domestic wines, or the green twigs or cuttings of vines) is placed. One of these vessels is wholly, and the other only about 3-4ths, filled. The fermentation recommences, and the acetification proceeds more rapidly in the latter than in the former tun, and the liquor it contains consequently matures the sooner. When fit for sale, a portion of the vinegar is withdrawn from the smaller quantity, and its place supplied with a like quantity from the full tun, and this in its turn is refilled from the barrels before noticed. This process is carried on with a number of tuns at once, which are all worked in pairs.

_Prop., &c._, The general properties of malt vinegar are well known. Its pleasant and refreshing odour is chiefly derived from acetic acid and acetic ether. Its strength is distinguished by the makers as Nos. 18, 20, 22, and 24; the last of which, also called ‘proof vinegar,’ is the strongest, and usually contains about 4·6% of real or about 5% of glacial acetic acid. Its density varies according to the quantity of foreign matter which it contains. Sp. gr. 1·017 to 1·019——B. P. This vinegar usually contains a small quantity of sulphuric acid. The presence of 1-1000th part of this acid is allowed by law.

_Pur._ “Brownish; of a peculiar odour. Its sp. gr. is 1·019. 1 fl. oz. of the acid is saturated by 1 dr. of the crystals of carbonate of soda. If, after 10 minims of solution of chloride of barium have been added to the same quantity, more of the chloride be poured into the filtered acid, nothing further is thrown down. The colour is not changed by the addition of hydrosulphuric acid.” (Ph. L.)

2. WINE VINEGAR, FRENCH V.; ACETUM GALLICUM (Ph. E. & D.), A. VINI, L.; VINAIGRE D’ORLEANS, Fr. This is prepared, in wine countries, from grape juice and inferior new wines, worked up with wine-lees, by a nearly similar process to that adopted for malt vinegar. That prepared from white wine (WHITE-WINE VINEGAR) is the most esteemed. It is purer and pleasanter than malt vinegar. Sp. gr. 1·014 to 1·022——Ph. E.; 1·016——Phillips. It usually contains from 5 to 6% of acetic acid. “100 parts of good Orleans vinegar should require 10 parts of dry carbonate of potassa for saturation.” (Soubeiran.)

3. GERMAN, OR QUICK-METHOD OF MAKING VINEGAR; PROCESS OF HAM. This method is based upon the fact, that acetification is the mere oxidation of alcohol in contact with organic matter. Hence, by employing dilute alcohol, or liquors containing it, and by vastly enlarging the surface of the liquid exposed to the air at a proper temperature, we may reduce the period occupied in acetification from weeks to as many hours. In practice this is effected by causing the dilute spirit, previously mixed with 1-1000th part of sugar or malt extract, or the fermented and clarified malt-wort, to slowly trickle down through a mass of beech shavings steeped in vinegar, and contained in a vessel called a vinegar generator (essigbilder), or graduation vessel. This is an oaken tub, narrower at the bottom than at the top, furnished with a loose lid or cover, below which is a perforated shelf (colander or false bottom), having a number of small holes, which are loosely filled with packthread about 6 inches long, and prevented from falling through by a knot at the upper end. The shelf is also perforated with four open glass tubes, as air-vents, each having its ends projecting above and below the shelf. This arrangement is repeated a second and a third time, or even oftener, according to the size of the vessel. The tube or graduator at its lower part is pierced with a horizontal row of eight equidistant round holes, to admit atmospheric air. One inch above the bottom is a syphon-formed discharge pipe, whose upper curvature stands one inch below the level of the air-holes in the side of the tub. The floors or partitions of the tub or generator being covered with birch twigs or beech chips to the depth of a few inches, the alcoholic liquor (first heated to between 75° and 83° Fahr.,) is introduced at the upper part of the apparatus. This immediately commences trickling slowly down through the holes by means of the packthreads, diffuses itself over the chips or twigs forming the respective strata, slowly collects at the bottom of the tub, and then runs off by the syphon-pipe. The air enters by the circumferential holes, circulates freely through the tub, and escapes by the glass tubes. As the acetification proceeds, the temperature of the liquid rises to 100° or 105° Fahr., and remains stationary at that point while the action goes on favorably. The alcoholic solution or wort requires to be passed three or four times through the cask before acetification is complete, which is, in general, effected in from 24 to 36 hours.

_Obs._ For the production of a superior vinegar by this process, it is necessary that the spirit employed be sufficiently pure not to contaminate the product with its flavour or odour, and that the malt-wort should be fermented and treated with all the care usually employed in the production of beer. The best English manufacturers who have adopted this process are in the habit of filtering or clarifying their fermented wash, and also of storing it away for several months before they subject it to acetification in the graduator. The most favorable temperature for the process is about 90° Fahr., and this should be preserved, as much as possible, by artificial means. _Prod._ A malt-wort of the sp. gr. 1·072, or, in “technical language, weighing about 26 lbs. per barrel, afforded a vinegar containing 5·4% of pure acetic acid, and a residuary extract of 10 lbs., for 36 galls. The former of these would indicate 35 lbs. of sugar, or 13·7 lbs. per barrel of gravity; whilst the latter shows 3·8 lbs. per barrel; the two united being only 17·5 lbs., instead of 26, the original weight. The loss, therefore, has been 8·5 lbs., or from a sp. gr. of 1·072 to less than 1·050.” (Ure.) Thus, about one third of all the extractive matter of the malt is lost or dissipated during the processes of fermentation and acetification. According to Knapp, a mixture of about 80 galls, of water, 9 galls. of spirit of from 44 to 45% Tralles (18 or 20 u. p.), and 3 galls. of vinegar containing 3·5% of real acid, forming together 92 galls., yield, on an average, an almost equal quantity of vinegar, or about from 90 to 91 galls. of the above stated strength.

4. WOOD VINEGAR. See PYROLIGNEOUS ACID.

5. OTHER VARIETIES OF VINEGAR, of minor importance; chiefly domestic, and commonly ‘worked’ as malt vinegar,——ALE VINEGAR, ALEGAR; ACETUM CEREVISIÆ. From strong pale ale which has soured.——ARGOL VINEGAR; ACETUM EX TARTARO. From white argol or cream of tartar, 1 lb.; dissolved in boiling water, 2 galls.; with the addition, when cold, of proof spirit of whiskey, 3 pints.——CRYSTAL VINEGAR. Pickling vinegar, discoloured with fresh burnt animal charcoal.——CIDER VINEGAR. From cider, worked as malt vinegar.——GERMAN HOUSEHOLD VINEGAR. From soft water, 7-1/2 galls.; honey or brown sugar, 2 lbs.; cream of tartar, 2 oz.; corn spirit or whiskey, 1 gall.——GOOSEBERRY VINEGAR. From bruised gooseberries and brown sugar, of each 1-1/4 lb.; water, 1 gall. Other fruits may be substituted for gooseberries.——PICKLING VINEGAR. The strongest pale malt vinegar——RAISIN VINEGAR. From the marc left from making raisin wine, 1 cwt. to every 12 or 15 galls. of water, along with a little yeast.——SUGAR VINEGAR. From brown sugar, 4 lbs. to each gallon of water.——WHISKEY VINEGAR. From whiskey, 1 pint; sugar, 2 oz.; yeast, a dessert-spoonful.

_Pur., Tests, and Assay._ These are, for the most part, rather fully noticed under ACETIC ACID, ACETIMETRY, and above. The following additional tests, &c., may, however, be useful:——1. Paper written on or smeared with pure vinegar is not charred when strongly warmed before the fire; if it is, the sample examined contained fully 2% of oil of vitriol.——2. A small porcelain capsule, or china cup, dipped into a solution of sugar in 30 times its weight of water, and then heated to a temperature equal to that of boiling water, is not materially discoloured when a drop of pure vinegar is poured on it; but a spot of an intensely brown or black colour is formed if the sample contains only 1-300th part of sulphuric acid; if it contains only 1-1000th part, the spot is olive green; and if a less quantity, then only of a pale green colour.——3. The heavy white precipitate given with chloride of barium (see _above_) shows the presence of sulphuric acid; each grain, after being dried, and gently ignited, represents ·344 gr. of dry sulphuric acid. If the precipitate from 1000 gr. of the vinegar exceeds 2-1/2 gr., it contains an illegal quantity of this acid.——4. If a solution of nitrate of silver gives a cloudy white precipitate, hydrochloric acid is present.——5. If, after the addition of 2 or 3 gr. of carbonate of potash, and evaporation of the sample to dryness, the residuum deflagrates when ignited, the sample under examination contains nitric acid.——6. If the vinegar be blackened by sulphuretted hydrogen or hydrosulphuret of ammonia, it contains either lead or copper. If it gives a yellow precipitate with iodide of potassium or chromate of potash, the metal is lead. If ferrocyanide of potassium gives a bronze-brown coloured precipitate, or a little olive oil, when agitated with some of the vinegar, be turned green, the metal is copper.——7. If a small sample, gently evaporated to dryness, leaves more than 1% of residuum, and this has a sweet taste, it is undecomposed sugar. The presence of acrid substances, as capsicum, chillies, grains of paradise, mustard seed, pellitory of Spain, pepper, &c., may be detected by neutralising the acidity of the vinegar with carbonate of soda, when the acrid taste of the adulterant will be readily perceived.

=Vinegar, Anti′hysteric.= _Syn._ ACETUM ANTI′HYSTERICUM. _Prep._ Castor, 2 dr.; galbarium, 4 dr.; rue, 1 oz.; vinegar, 3 lbs.; macerate and strain.

=Vinegar, Aromat′ic.= _Syn._ ACETUM AROMATICUM, L. _Prep._ 1. Glacial acetic acid, 1 lb.; oil of cloves, 1-1/2 dr.; oil of rosemary, 1 dr.; oils of bergamot, cinnamon, pimento, and lavender, of each 1/2 dr.; neroli, 20 drops; camphor, 2-1/2 oz.; rectified spirit, 2 fl. oz.; mix. Very fine.

2. (Henry’s.) From glacial acetic acid, strongly scented with the oils of cloves, lavender, rosemary, and _Calamus aromaticus_ to which the usual quantity of camphor is added. This is the formula adopted at Apothecaries’ Hall.

3. (Extemporaneous.) From acetate of potash (dry), 1 dr.; oil of vitriol, 20 drops; oils of lemon and cloves, of each 3 drops.

_Obs._ Aromatic vinegar is used as a pungent and refreshing perfume, in faintness, &c. For this purpose it is generally dropped on a small piece of sponge placed in a stoppered bottle or a vinaigrette. It is highly corrosive, and should therefore be kept from contact with the skin and clothes.

=Vinegar, Camp.= _Prep._ Take of sliced garlic, 8 oz.; Cayenne pepper, soy, and walnut ketchup, of each 4 oz.; 36 chopped anchovies; vinegar, 1 gall.; powdered cochineal, 1/2 oz.; macerate for a month, strain, and bottle.

=Vinegar, Cam′phorated.=

=Vinegar of Canthar′ides.= _Syn._ BLISTERING VINEGAR; ACETUM CANTHARIDIS (B. P., Ph., L. E. & D.), L. _Prep._ 1. (Ph. L.) Cantharides, in powder, 2 oz.; acetic acid, 1 pint; macerate, with agitation, for 8 days, then press, and strain.

2. (Ph. E.) Cantharides, 3 oz.; euphorbium, 1/2 oz.; acetic acid, 5 fl. oz.; pyroligneous acid, 15 fl. oz.; macerate a week.

3. (Ph. D.) Spanish flies, 4 oz.; strong acetic acid, 4 fl. oz.; commercial acetic acid (sp. gr. 1·044), 16 fl. oz.; macerate, as before, for 14 days.

4. (B. P.) Cantharides, in powder, 2; glacial acetic acid, 2; acetic acid (28 per cent.), 18, or a sufficiency: add the glacial acetic acid to 13 of acetic acid, and in this mixture digest the cantharides for two hours at a temperature of 200° F.; when cold, place them in a percolator, and when the liquid ceases to drop, pour over the residuum the remaining 5 of acetic acid, and when the percolation is finished, press and make the whole liquid up to 20.

_Uses, &c._ As a counter-irritant, and to raise blisters. For the last purpose it is applied on a piece of lint, evaporation being prevented with a piece of oiled skin or thin sheet gutta percha. The last is the best, and, indeed, the only effective form; the others being too weak. “If the acetic acid be strong, a blister will be as rapidly raised without the cantharides as with them.” (Dr A. T. Thomson.)

=Vinegar of Capsi′cum.= _Syn._ ACETUM CAPSICE. _Prep._ Capsicum, 1 oz.; vinegar, 24 oz. Used as gargle.

=Vinegar of Col′chicum.= _Syn._ ACETUM COLCHICI (Ph. L. E. & D.), L. _Prep._ 1. (Ph. L.) Dried corms of colchicum or meadow saffron, 3-1/2 dr.; dilute acetic acid, 1 pint; macerate for 3 days, then press out the liquor, and, after defecation, add to the strained liquid proof spirit, 1-1/2 fl. oz.

=Vinegar, Cur′rie.= _Prep._ From currie powder, 1/2 lb.; vinegar, 1 gall.; infuse for a week. Used as a flavouring. Other like vinegars may be made in the same way.

=Vinegar of Gar′lic.= _Syn._ ACETUM ALLII. _Prep._ Fresh garlic, 1 oz.; distilled vinegar, 12 oz.

2. (Ph. E.) Fresh colchicum bulbs (dried), 1 oz.; distilled vinegar, 16 fl. oz.; proof spirit, 1 fl. oz.

3. (Ph. D.) Dried colchicum bulbs, 1 oz.; acetic acid (1·044), 4 fl. oz.; distilled water, 12 fl. oz.; as before, but prolonging the maceration for 7 days.

_Obs._ Vinegar of colchicum is chiefly used in gout. _Dose_, 20 drops to 1 fl. dr. The Dublin preparation is about three times as strong as the others, and the dose must therefore be proportionately less.

=Vinegar, Distil′led.= _Syn._ ACETUM DESTILLATUM (Ph. L. & E., and Ph. D. 1826), L. _Prep._ 1. (Ph. L.) Vinegar, 1 gall.; distil in a sand bath, 7 pints. Sp. gr. 1·0065.

2. (Ph. E.) Vinegar (preferably French), 8 parts; distil over with a gentle heat, 7 parts; and dilute the product, if necessary, with distilled water, until the sp. gr. is 1·005.

_Pur., &c._ “1 fluid oz. is saturated by 57 gr. of crystallised carbonate of soda.” (Ph. L.) 100 gr. are saturated by 13 gr. of crystallised carbonate of soda. It contains about 4·6% of real acetic acid. If a pewter worm is used, a portion of lead is dissolved, and the product becomes cloudy and poisonous. Distilled vinegar is more agreeable than pure dilute acetic acid of the same strength.

=Vinegar of Fox′glove.= _Syn._ ACETUM DIGITALIS. (Ph. G.) _Prep._ Dried foxglove, 1 oz.; vinegar, 9 oz. (by weight); rectified spirit, 1 oz. (by weight). Macerate for 8 days, press and filter.——_Dose_, 30 minims.

=Vinegar of Lav′ender.= _Syn._ ACETUM LAVANDULÆ. (P. Cod.) _Prep._ Digest 1 troy oz. of dried lavender flowers with 12 oz. of vinegar for 10 days. The vinegars of other flowers are made in the same manner.

=Vinegar of Lobelia.= _Syn._ ACETUM LOBELIÆ. _Prep._ Lobelia in moderately coarse powder, 4 troy oz. Diluted acetic acid, 2 pints (o. m.). Macerate for 7 days.

=Vinegar, Marseilles.= _Syn._ VINEGAR OF THE FOUR THIEVES, PROPHYLACTIC VINEGAR; ACETUM PROPHYLACTICUM, A. ANTISEPTICUM, A. THERIACALE, A. QUATUOR FURUM, L.; VINAIGRE DES QUATRE VOLEURS, Fr. _Prep._ Take of the summits of rosemary and flowers of sage (dried), of each 4 oz.; dried lavender flowers, 2 oz.; cloves, 1 dr.; distilled vinegar, 1 gall.; digest for 7 days, press, and filter. Used as a corrector of bad smells, and formerly as a prophylactic against the plague, and other contagious diseases. It is said to have been a favourite preventive with Cardinal Wolsey, who always carried some with him. The original formula also contained, of garlic, 1/4 oz.; fresh rue, 1-1/2 oz.; and camphor, dissolved in spirit, 1 oz.

=Vinegar of Mus′tard.= _Syn._ ACETUM SINAPIS (Beral). _Prep._ Mustard, 1 oz.; vinegar, 12 oz.; distil 8 oz. For outward use, as a counter-irritant.

=Vinegar of O′′pium.= _Syn._ ACETUM OPII (Ph. E. & D.), L. _Prep._ 1. (Ph. E.) Opium, sliced, 4 oz.; distilled vinegar, 16 fl. oz.; macerate for 7 days, press, and filter.——_Dose_, 5 to 20 drops.

2. (Ph. D.) Opium, in coarse powder, 1-1/2 oz.; dilute acetic acid, 1 pint; macerate for 7 days.——_Dose_, 10 or 12 to 60 drops.

_Obs._ These were intended to supersede the old ‘black drop,’ which they closely resemble in their action.

=Vinegar, Rasp′berry.= _Syn._ ACETUM RUBI IDÆI, L.; VINAIGRE FRAMBOISE, Fr. _Prep._ 1. Bruised ripe raspberries and white wine vinegar, of each 3 pints; macerate for 3 days, press, strain, and to each pint add of white sugar, 1 lb.; boil, skim, cool, and at once bottle. Some persons add 2 fl. oz. of brandy to each pint.

2. (P. Cod.) Fresh raspberries, picked from their calices, 3 lbs.; (1 lb.——Ph. Bor.); good vinegar, 2 lbs.; macerate, in glass, for a fortnight, then strain, without pressure.

_Obs._ In a similar manner may be made cherry vinegar, strawberry vinegar, and the vinegars of all other like fruits.

=Vinegar of Rue.= _Syn._ ACETUM RUTÆ. (Ed. Ph. 1744). _Prep._ Rue, 1 lb. troy; vinegar, 1 gall.

=Vinegar of Squills.= _Syn._ ACETUM SCILLÆ (Ph. L. E. & D.), ACEUM SCILLITICUM, L. _Prep._ 1. (Ph. L.) Take of squills, recently dried and bruised, 2-1/2 oz.; dilute acetic acid, 1 pint; macerate with a gentle heat in a covered vessel for 3 days, then press out the liquor, and, after defecation, add to the strained liquid, proof spirit, 1-1/2 fl. oz. The Edinburgh and Dublin Colleges direct cold maceration for 7 days in a glass vessel, and the Dublin omits the spirit.

2. (Wholesale.) From squills, 7 lbs.; distilled vinegar, 6 galls.; macerate in the cold for 10 days, press, and filter. Expectorant and diuretic.——_Dose_, 1/2 to 1-1/2 fl. dr.; in chronic pulmonary affections, dropsies, &c.

=Vinegars (Cul′inary).= _Prep._ 1. BLACK PEPPER VINEGAR, CAPER V., CAPSICUM V., CELERY-SEED V., CHILLIE V., CRESS-SEED V., GARLIC V., GINGER V., HORSERADISH V., ONION V., RED-ROSE V., SEVILLE-ORANGE-PEEL V., SHALLOT V., TRUFFLE V., WHITE PEPPER V., with several others of a like kind, are made by steeping about an oz. of the respective articles in a pint of good vinegar for 14 days, and straining.

2. BASIL V., BURNET V., CELERY V., CHERVILLE V., ELDER-FLOWER V., GREEN-MINT V., TARRAGON V., with several others from like substances, are prepared from 2 to 3 oz. of the leaves to each pint of vinegar; the whole being frequently shaken for 14 days, then strained and bottled. They are used in cookery. The culinary vinegars may also be prepared in the same manner as the ‘culinary spirits’ and ‘tinctures,’ by simply substituting strong pickling vinegar for the spirit.

=Vinegars (Perfumed).= _Syn._ ACETA ODORIFERA, L. _Prep._ From the dried flowers, 1 to 2 oz., or the fresh flowers, 2 to 4 oz.; strongest distilled vinegar, 1 pint; digest for a week, strain with pressure, and repeat the process with fresh flowers if necessary. They may also be made by adding 15 to 20 drops, or q. s., of the respective essential oils to the vinegar. In a similar way are prepared the vinegars of clove-gilly flowers, elder flowers, lavender f. (vinaigre distillé de lavande), musk roses, orange flowers (fresh), Provins roses, red roses (vinaigre de rose; acetum rosatum), rosemary flowers (vinaigre de rosmarin; acetum anthosatum), tarragon flowers, &c. &c. Another excellent plan is to add 1 fl. oz. of glacial acetic acid to each pint of the respective perfumed spirits. This answers admirably for acetic eau de Cologne and like perfumes.

=VI′NOUS FERMENTATION.= _Syn._ ALCOHOLIC FERMENTATION. The peculiar change by which sugar, in solution, is converted into carbonic acid, which is eliminated, and into alcohol, which remains in solution in the fermented liquor.

The presence of a ‘ferment’ is essential to excite the vinous fermentation, as a solution of absolutely pure sugar remains unaltered, even though exposed to the conditions most favourable to its accession. In the juices of the sweet fruits, and in those vegetable solutions that spontaneously run into a state of fermentation, the ferment is supplied by nature, and is intimately associated with the saccharine matter. In the juice of those grapes which produce the more perfect wines, the relative proportions of the exciters of fermentation and the sugar are so accurately apportioned, that the whole of the former are decomposed, and nearly the whole of the latter is converted into alcohol; so that the liquid (wine) is left in a state but little liable to future change. An infusion of malt, however, in which the nitrogenised matters (gluten, vegetable albumen, &c.) are absent, or at least present in too small quantities to vigorously excite the vinous fermentation, undergoes a mixed species of decomposition, with the formation of products widely different from those that result from the true vinous fermentation; or, in other words, the liquid becomes spoiled. But if a ferment (yeast) be added to this infusion of malt under the above circumstances, and in the proper proportion to the sugar present, the true vinous fermentation speedily commences, and the liquid becomes converted into beer. This is what actually takes place in the process of brewing, and the scientific brewer endeavours to employ a proper quantity of ferment to decompose the whole of the saccharine matter of his wort; but, at the same time, as equally endeavours to avoid the use of an excess.

The chief product of the vinous fermentation is alcohol, but there are other substances simultaneously produced, and which remain associated with the fermented liquor. Among the principal of these are œnanthic acid, œnanthic ether, fusel oil (oil of potato spirit, oil of grain), &c.; none of which exist previously to fermentation, and are generally supposed to result from the action of the nitrogenised matters of the solution on the sugar. Under certain circumstances these extraneous products are formed in much larger quantities than under others; and as these substances injure the value of the alcohol with which they are associated, a knowledge of the peculiar circumstances favourable and unfavourable to their production is a desideratum to the brewer and distiller.

According to MM. Colin and Thénard, Frémy, Rousseau, and others, the essential condition of a ferment, to be able to excite the pure vinous fermentation, is to be sufficiently acidulous to act on coloured test-paper; and this acidity should arise from the presence of certain vegetable acids and salts, capable of conversion into carbonic acid and carbonates by their spontaneous decomposition. Those acids and salts which are found to pre-exist in fermentable fruits and liquors, as the tartaric, citric, malic, and lactic acids, and their salts should be chosen for this purpose; preference being given to the bitartrate of potassa, on account of its presence in the grape. The addition of any of these substances to a saccharine solution renders its fermentation both more active and complete. The favorable influence of cream of tartar on fermentation was first pointed out by Thénard and Colin, and the addition of a little of this article has been adopted in practice, with manifest advantage, by the manufacturers of British wine.

There is good reason for supposing that each variety of sugar which is susceptible of the alcoholic fermentation is first converted into grape sugar by contact with the ferment, and that this variety of sugar is alone capable of yielding carbonic acid and alcohol.

The circumstances most favorable to this fermentation are, a certain degree of warmth, a sufficient quantity of active ferment, and its due distribution through the liquor. The temperature of from 68° to 77° Fahr. is usually regarded as the most propitious for the commencement and progress of fermentation; but it has been ably shown by Liebig that, at this temperature, the newly formed alcohol slowly undergoes the ‘acetous fermentation,’ forming vinegar, by which the vinous character of the liquor is lessened. This conversion of alcohol into vinegar proceeds most rapidly at a temperature of 95° Fahr., and gradually becomes more languid, until, at about 46° to 50° Fahr. (8 to 10 Cent.), it ceases altogether, while the tendency of the nitrogenous substances to absorb oxygen at this low temperature is scarcely diminished in a perceptible degree. “It is therefore evident that if wort (or any other saccharine solution) is fermented in wide, open, shallow vessels, as is done in Bavaria, which afford free and unlimited access to the atmospheric oxygen, and this in a situation where the temperature does no exceed 46° to 50° Fahr., a separation of the nitrogenous constituents, _i. e._ the exciters of acidification, takes place simultaneously on the surface, and within the whole body of the liquid.” (Liebig.) By this method wine or beer is obtained, which is invariably far superior in quality to that fermented in the usual manner. See FERMENTATION.

The symptoms of a perfect fermentation of malt wort, according to the usual English system with top yeast (_oberhefe_), have been thus described by a well-known practical writer on brewing: 1. A cream-like substance forms round the edges of the gyle tun, which gradually extends itself, and ultimately covers the whole surface of the liquor. 2. A fine curly or cauliflower head in a similar way extends itself over the surface, and indicates to the experienced brewer the probable quality of the fermentation. 3. The ‘stomach,’ or ‘vinous odour,’ is next evolved, and continues to increase with the attenuation of the wort. The peculiar nature of this odour is also an indication of the state of the fermentation.——4. The cauliflower head changes, or rises to a fine ‘rocky’ or ‘yeasty’ head, and ultimately falls down.——5. In this stage the head assumes a peculiar ‘yeasty’ appearance, called by brewers ‘close-yeasty,’ and the gas is evolved in sufficient quantity to blow up little bells or bubbles, which immediately burst, and are followed by others, at intervals depending on the activity and forwardness of the fermentation. These bells should be bright and clear; as, if they appear opaque or dirty, there is something the matter with the wort. (Black.)

It is often of the utmost importance to brewers, wine merchants, sugar refiners, druggists, &c., to be able to lessen the activity of the vinous fermentation, or to stop it altogether, or to prevent its accession to syrups and other saccharine and vegetable solutions. Whatever will still the motion of the molecules of the nitrogenous matter forming the ferment will render them inoperative as exciters of fermentation. Among the simplest means of effecting this object, and such as admit of easy practical application, may be mentioned exposure to either cold or heat. At a temperature below about 50° Fahr., the acetous fermentation is suspended, and the alcoholic fermentation proceeds with diminished activity as the temperature falls, until at about 38° Fahr. it ceases altogether. In like manner, the rapid increase of the temperature of a fermenting liquid arrests its fermentation, and is preferable to the action of cold, as it is of easier application, and perfectly precipitates the ferment in an inert state. For this purpose a heat of about 180° Fahr. is sufficient: but even that of boiling water may be employed with advantage. In practice fluids are commonly raised to their boiling point for this purpose, or they are submitted to the heat of a water bath (207-1/2° Fahr.). In this way the fermentation of syrups and vegetable solutions and juices is commonly arrested in the pharmaceutical laboratory.

Among substances that may be added to liquids to arrest fermentation the most active are——the volatile oil of mustard, coarsely powdered mustard seed, or pure flour of mustard, sulphurous acid or the fumes of burning sulphur, sulphuric acid, sulphite of lime, tincture of catechu, strong spirit, strong acetic acid, chlorate of potassa, sugar of milk, bruised horseradish, garlic, and cloves, and their essential oils, and all the other volatile oils that contain sulphur, and most of the salts that readily part with their oxygen. These substances arrest fermentation by rendering the yeast inoperative, and they possess this power nearly in the order in which they stand above. In practice, mustard, the fumes of burning sulphur, sulphite of lime, and chlorate of potassa, are those most adapted for beer, cider, wines, syrups, &c.; but some of the others are occasionally used, though less active. For arresting or preventing the fermentation of the vegetable juices and solutions, and the medicated syrups employed in pharmacy, mustard seed, either alone or combined with a little bruised cloves, may be safely used, as the addition of acids or salts would lead to the decomposition of their active principles. For this reason such liquids should be kept in a sufficiently low temperature to prevent fermentation; and should they pass into that state it should be preferably arrested by the application of heat or cold, as above explained. Sugar of milk is also very effective for certain syrups, if not all of them.

To prevent, or rather to lessen, the production of fusel oil, it has been proposed to add a certain quantity of tartaric acid or bitartrate of potassa to the wort, or to arrest the fermentative process somewhat before the liquid has reached its utmost degree of attenuation. The best means of depriving the spirit of this and other substances of a similar nature is to largely dilute it with water, and to redistil it at a gentle heat. Agitation with olive oil, decantation, dilution with a large quantity of water, and redistillation, have also been recommended. An excellent method is filtration through newly burnt and coarsely powdered charcoal. This plan succeeds perfectly with moderately diluted spirit. On the Continent, the addition of about 10% of common vinegar, and a very little sulphuric acid, followed by agitation, repose for a few days, and redistillation is a favourite method. A solution of chloride of lime is also employed for the same purpose, and in the same way. In both these cases a species of ether is formed, which possesses a very agreeable odour. In the first, acetate of oxide of amyl (essence of jargonelle) is produced; and in the other, chloride of amyl, which also possesses a pleasant ethereal smell and taste. The affinity of the hydrated oxide of amyl (fusel oil) for acetic acid is so great, that they readily unite without the intervention of a mineral acid. (Doebereiner). Thus, the oil of vitriol mentioned above, though always used in practice, might be omitted without any disadvantage.

According to Messrs Bowerbank, the distillers quoted by Dr Pereira, 500 galls. of corn-spirit yield about one gall. of corn-spirit oil. See ACETIFICATION, ALCOHOL, BREWING, DISTILLATION, FERMENTATION, FUSEL OIL, SPIRIT, VINEGAR, VISCOUS FERMENTATION, YEAST, &c.

=VI′OLET.= _Syn._ PURPLE VIOLET, SWEET V.; VIOLA (Ph. L. & E.), L. “The recent petals of _Viola odorata_, Linn.” (Ph. L.) It is chiefly used on account of its colour. See SYRUP.

=VIOLET DYE.= Violet, like purple, is produced by a mixture of red and blue colouring matter, applied either together or in succession. The ‘aniline colours’ are now almost exclusively used for obtaining violet on silk and wool (see ANILINE, PURPLE, and TAR COLOURS). With the old dye stuffs, violet may thus be obtained:——A good violet may be given to silk or wool by passing it first through a solution of verdigris, then through a decoction of logwood, and, lastly, through alum water. A fast violet may be given by first dyeing the goods a crimson with cochineal, without alum or tartar, and, after rinsing, passing them through the indigo vat.——Linens and cottons are first galled with about 18% of gall-nuts, next passed through a mixed mordant of alum, iron liquor, and sulphate of copper, working them well, then through a madder bath made with an equal weight of root, and, lastly, brightened with soap or soda. Another good method is to pass cloth, previously dyed Turkey red, through the blue vat. Wool, silk, cotton, or linen, mordanted with alum and dyed in a logwood bath, or a mixed bath of archil and Brazil, takes a pretty, but false, violet.

=VIS′COUS FERMENTATION.= _Syn._ MUCILAGINOUS FERMENTATION, MUCOUS F. The peculiar change by which sugar, in solution, is converted into gummy matters, and other products, instead of into alcohol.

When the expressed juice of the beet is exposed to a temperature of 90° to 100° Fahr., for a considerable time, the sugar it contains suffers this peculiar kind of fermentation. Gases are evolved which are rich in hydrogen, instead of being exclusively carbonic acid, and when the sugar has, for the most part, disappeared, mere traces of alcohol are found in the liquid, but, in place of that substance, a quantity of lactic acid, mannite, and a mucilaginous substance, resembling gum Arabic, and said to be identical with gum in composition. By boiling yeast or the gluten of wheat in water, dissolving sugar in the filtered solution, and exposing it to a tolerably high temperature, the viscous fermentation is set up, and a large quantity of the gummy principle generated, along with a ferment of a globular texture, like that of yeast, but which is capable of producing only the viscous fermentation, in saccharine solutions.

The peculiar cloudy, stringy, oily appearance of wine and beer, called by the French ‘graisse,’ and the English ‘ropiness,’ depends on the accession of the viscous fermentation. The mineral acids and astringent substances, especially the sulphuric and sulphurous acids, and tannin, precipitate the viscous ferment, and are, hence, the best cures for this malady of fermented liquors. It is the large amount of tannic acid in the red wines and well-hopped beer which is the cause of their never being attacked with ‘graisse,’ or ‘ropiness.’ See VINOUS FERMENTATION, WINES, &c.

=VI′′SION.= The following means of preserving and restoring the sight may be appropriately inserted here:——

For NEAR-SIGHTEDNESS.——Close the eyes and press the fingers very gently, from the nose outward, across the eyes. This flattens the pupil, and thus lengthens or extends the angle of vision. This should be done several times a day, or at least always after washing the face, until shortsightedness is overcome.

For LOSS OF SIGHT BY AGE, such as require magnifying glasses, pass the fingers or towel from the outer corners of the eyes inwardly, above and below the eyeballs, pressing very gently against them. This rounds them up, and preserves or restores the sight.

It is said that many persons, by this last means, have preserved their sight so as to read fine print at 80 years of age; others, whose sight has been impaired by age, by carefully manipulating the eyes with their fingers, from their external angles inwardly, have restored their sight, and been able to dispense with glasses, and have since preserved it by a continuance of the practice. To be successful, or safe, these practices must be applied with great gentleness and caution. Many persons seriously damage their eyes by forcibly rubbing them when drowsy, especially on awaking in the morning.

The ‘Lancet’ remarks, that “there is good reason to believe that chicory (the coffee of the Londoners), from its narcotic character, exerts an injurious effect on the nervous system. So convinced of this is Professor Beer, of Vienna, a most celebrated German oculist, that he has enumerated chicoried coffee among the causes of amaurotic blindness.”

To strengthen the eyes, to relieve them when swollen or congested, and to remove chronic ophthalmia, purulent discharges, &c., nothing is equal to frequently bathing them with water, at first tepid, but afterwards lowered in temperature to absolute coldness.

=VIT′RIOL.= A common name for sulphuric acid and for several of its salts. (See _below_.)

=Vitriol, Blue.= _Syn._ ROMAN VITRIOL. Commercial sulphate of copper.

=Vitriol, Green.= Commercial sulphate of iron.

=Vitriol, White.= Commercial sulphate of zinc.

=VITTIE VAYR.= _Syn._ VETIVER. The Tamool name of the odorous and fibrous roots of the _Andropogon muricatus_ sold by the perfumers.

=VOLTA′IC ELECTRICITY.= _Syn._ GALVANIC E., GALVANISM, VOLTAISM. That branch of electrical science which has reference to the phenomena attendant on the development of electricity by chemical action. Electricity thus developed may be made to show itself in the ‘static’ condition, so as to produce the effects of frictional electricity, but it is much more easily obtained in the ‘dynamic’ condition——in other words, as a ‘voltaic current’——when it is especially remarkable for its chemical and magnetic effects. If a plate of zinc and a plate of platinum be immersed in dilute sulphuric acid, and connected outside the liquid by a wire, a current of electricity will immediately be set up, and will continue as long as the conducting circuit is complete and the action of the acid on the zinc goes on. The current of ‘positive’ electricity passes from the zinc, through the liquid, to the platinum, and thence through the wire to the zinc. The arrangement of two dissimilar metals immersed in a liquid which acts upon one of them is called a voltaic couple. By uniting a number of couples together in regular order, a voltaic pile or battery is formed.

The older forms of the voltaic battery, viz., VOLTA’S PILE, CRUIKSHANK’S TROUGH, and WOLLASTON’S BATTERY, are now but little used. They all consist of a series of couples of zinc and copper, excited by an acid liquid, generally a mixture of water with 1/40th of its bulk of sulphuric acid, and 1/60th of nitric acid.

_A._ A copper cylinder, filled with a saturated solution of sulphate of copper.

_B._ A smaller porous cylinder (earthenware or membrane), containing a mixture of 1 measure of strong sulphuric acid, and about 8 measures of water.

_C._ A rod of amalgamated zinc, supported in the smaller cylinder by the cross-piece (_i_).

_D._ A shelf full of small holes, for supporting crystals of sulphate of copper, to keep up the strength of the solution.

_e_ and _f._ Screws and caps to connect the wires _g_ and _h_ with the battery.

_g._ The negative wire, connected with the zinc.

_h._ The positive wire, connected with the copper.]