Chapter II: Deposition of the Precious Metals (5)

2. As the strongest _Eau de lavende_. See SPIRIT.

=Essence of Lavender (Red).= See SPIRIT and TINCTURE.

=Essence of Lem'on.= _Syn._ ESSENTIA LIMONIS, L. _Prep._ 1. See OIL (Volatile).

2. (W. Procter.) Fresh oil of lemons, 1 fl. oz.; deodorised alcohol (strongest flavourless rectified), 8 fl. oz.; exterior yellow rind of lemons (fresh), 1/2 oz.; digest 48 hours, and filter. Used for flavouring mixtures, pastry, &c.

3. From oil of lemons, as ESSENCE OF ALLSPICE. Used as the last.

=Essence of Lemon Peel.= _Syn._ ESSENCE OF LEMON RIND, QUINTESCENCE OF L. P.; ESSENTIA CORTICIS LIMONIS, L. _Prep._ 1. Yellow peel of fresh lemons, 1/2 lb.; spirit of wine, 1 pint; digest for a week, press, and filter. Very fragrant.

2. Yellow peel of fresh lemons, 1 lb.; boiling water, 1/2 gall.; infuse 1 hour, express the liquor, boil down to 1/2 pint, cool, and add oil of lemon, 1/4 oz., dissolved in spirit of wine, 1-1/2 pint; mix, and filter. Used as the preceding.

=Essence of Lov'age.= _Syn._ ESSENTIA LEVISTICI, L. _Prep._ (Ph. Wurt.) Lovage root (_levisticum officinale_), 2 oz.; lovage seeds, 1 oz.; rectified spirit, 10 oz.; digest a week, and filter. Aromatic, stomachic, and diaphoretic.--_Dose_, 1/2 dr. to 1 dr.; in dyspepsia, dropsies, &c.

=Essence, Madden's.= Concentrated infusion of roses.

=Essence of Malt.= See COLOURING.

=Essence of Mint.= _Syn._ ESSENCE OF SPEARMINT; ESSENTIA MENTHÆ, E. M. SPICATÆ, E. M. VIRIDIS, L. _Prep._ As ESSENCE OF PEPPERMINT.

=Essence of Moss-Rose= (from the 'Chemist and Druggist'). Otto of rose, 1-1/2 dr.; essence of ambergris, 2-1/2 oz.; essence of musk, 1 oz.; alcohol, 15 oz.; concentrated rose water, 10 oz. Mix, and shake frequently for a week.

=Essence of Musk.= _Syn._ ESSENTIA MOSCHI, TINCTURA M. CONCENTRATA, L. _Prep._ 1. Grain musk, 2 oz., and boiling water, 1 pint, are digested together in a close vessel until cold, when rectified spirit of wine, 7 pints, is added; the vessel (preferably a tin bottle) being corked close, and tied over with bladder, the whole is digested, with frequent agitation, for 2 months, in the sunshine (in summer), or in an equally warm situation in winter. At the end of the time the essence is decanted and filtered.

2. Grain musk, 1/4 oz.; rectified spirit of wine, 2 pints; essence of ambergris, 1 fl. oz.; digest as before.

3. Musk (from the bladder, rubbed very small), 5 oz.; civet, 1 oz.; essence of ambergris, 1 pint; spirit of ambrette, 1 gall.; as before.

_Obs._ All the preceding formulæ yield superior essences, but the product of the last is of the very finest quality, and such as is seldom sold, except by the most celebrated houses, when it fetches a very high price. It is powerfully and deliciously odorous, and has received the approval of royalty itself, both in these kingdoms and on the Continent. The second formula also produces a very fine article, but less choice than just referred to. The digestion should be long continued, and on no account less than 3 weeks, as otherwise much fragrant matter is left undissolved. The addition of 1 fl. dr. of either liquor of ammonia or liquor of potassia (the first is best) to each pint of the essence, vastly increases its fragrance. The essence of musk of the wholesale London druggists is generally made by merely digesting the freshly emptied musk pods in rectified spirit. Sometimes a little (a very little) grain musk is added. See ESSENCE ROYALE and ESSENCE OF AMBERGRIS.

4. (Guibourt.) Musk, 1 part; proof spirit, 12 parts; digest a fortnight, or longer. Used in dispensing, &c.

=Essence of Musk Seed.= See ESSENCE D'AMBRETTE.

=Essence of Mus'tard.= _Syn._ ESSENTIA SINAPIS, L. _Prep._ (Whitehead's.) Black mustard seed (bruised), and camphor, of each 2 oz.; oil of rosemary, 3 dr.; balsam of tolu, 1 dr.; annatto, 1/2 dr.; digest a week, and filter.

=Essence of Myr'tle.= _Syn._ ESSENCE OF MYRTLE BLOSSOMS; ESSENCE DE MYRTE, ESPRIT DE M., Fr. _Prep._ Myrtle tops (in blossom), 2-1/2 lbs.; proof spirit, 9 pints; digest 3 days, then distil 1 gall. A pleasant perfume. See OIL (Volatile).

=Essence of Nero'li.= _Syn._ ESSENCE DE FLEURS D'ORANGES, ESPRIT DE F. D'O., Fr. _Prep._ 1. Neroli, 3 dr.; rectified spirit of wine, 1 pint; mix. A delicious perfume.

2. Oil of orange, 2 dr.; orris root (bruised), 1/2 oz.; ambergris, 10 gr.; neroli, 35 drops; spirits of wine, 1 pint; digest 14 days, and filter. Very fragrant, but less 'chaste' than the last.

=Essence of Nut'meg.= _Syn._ ESSENTIA MYRISTICÆ, E. M. MOSCHATÆ, E. NUCIS M., L. _Prep._ From essential oil of nutmeg, as ESSENCE OF ALLSPICE. Used as a flavouring or zest by cooks, liqueuristes, and confectioners.

=Essence, Odontal'gic.= See ESSENCE, TOOTHACHE.

=Essence d'[OE]illets.= [Fr.] _Prep._ From cinnamon, 3 oz.; cloves, 1-1/4 oz. (both well bruised); rectified spirit, 1 quart; digest for a week. Oil of cloves and spirit of cloves also bear this name in some places.

=Essence of O'pium.= See ESSENCE ANODYNE, No. 1. BLACK DROP and ROUSSEAU'S LAUDANUM have also been sometimes so called.

=Essence of O'range.= _Syn._ ESSENTIA AURANTII, L. _Prep._ As ESSENCE OF LEMON.

=Essence of Orange Peel.= _Syn._ ESSENTIA CORTICIS AURANTII, L. _Prep._ 1. (Golden.) Fresh yellow rind of orange, 4 oz.; rectified spirit and water, of each 1/2 pint; digest for a week, press, filter, and add of sherry wine, 1 quart. A pleasant liqueur.

2. (Saccharated.) See OLEO-SACCHARUM.

=Essence d'Orient.= [Fr.] A pearly-looking substance, found at the base of the scales of the blay or bleak, a small fish of the genus _cyprinus_.

_Prep._ The scales are scraped from the fish into a tub containing water, and after agitation and repose the fluid is poured off, and its place supplied with fresh water, and this in its turn, after agitation and repose, is also poured off. This part of the operation is repeated till the 'essence' and scales are perfectly freed from impurities, when the whole is thrown on a sieve, which retains the latter, but allows the former to flow through. After repose for a short time, the essence is obtained as a deposit at the bottom of the vessel.

_Obs._ Essence d'Orient has a bluish-white and pearly aspect, and is employed to cover the interior of glass bubbles and beads, in imitation of pearls and mother-of-pearl. Its tendency to putrefaction, while in the moist state, may be obviated by the addition of a little liquor of ammonia.

=Essence of Patch'ouli.= _Syn._ ESSENCE DE PATCHOULIE, ESPRIT DE POUCHÂ PÂT [Fr.]. _Prep._ 1. Indian patchouli (leaves or foliaceous tops), 2-1/2 lb.; rectified spirit, 9 pints; digest for a week; add of water, 1 gall.; oil of lavender (Mitcham), 3 dr.; common salt, 2 lbs.; agitate well together, distil over (rapidly) 1 gallon, and add of essence of musk, 3-1/2 fl. dr. A very fashionable perfume. Essence of patchouli, thus prepared, has been largely used, both at court and by the nobility generally.

2. Patchouli, 3 oz.; rectified spirit, 1 pint; digest a week, press, and filter. A still commoner kind is made with proof spirit.

=Essence of Pear.= _Syn._ ESSENCE OF JARGONELLE.

=Essence of Pen'nyroyal.= See ESSENTIA PULEGII, E. MENTHÆ P., L. _Prep._ From pennyroyal (_Mentha pulegium_), as ESSENCE OF PEPPERMINT. Stimulant, carminative, and emmenagogue. Used in dispensing, especially to make extemporaneous pennyroyal water.

=Essence of Pep'permint.= _Syn._ ESSENTIA MENTHÆ PIPERITÆ (B. P.) L. _Prep._ 1. (B. P.) Oil of peppermint, 1 part; rectified spirit, 4 parts. Mix.--_Dose_, 10 to 20 minims.

2. To the last add of herb peppermint, parsley leaves, or spinach leaves (preferably one of the first two), 1/2 oz., and digest for a week, or until sufficiently coloured. Sap green (10 or 12 gr., rubbed up with a teaspoonful of hot water) is also used for the same purpose. A delicate light green.

3. (Ph. U. S.) Oil of peppermint, 2 fl. oz.; rectified spirit, 16 fl. oz.

_Obs._ Essence of peppermint is not conceived to be good by the ignorant unless it has a pale-greenish tint, which they take as a proof of its being genuine. The most harmless way of tinging it is that indicated above. A little green mint or parsley will, indeed, be found to improve the flavour. These additions are quite harmless. The practice of using cupreous salts, adopted by some lazy and unprincipled makers, is unpardonable, and admits of no excuse, even a lame one, as not the least advantage, either of convenience, cost, or appearance, results from such a practice, while the colouring matter, though small in quantity, is nevertheless sufficient to impart a noxious quality to the liquid. This fraud may be detected by the addition of liquor of ammonia in excess, which will strike a bluish or greenish-blue colour when copper is present.

Essence of peppermint (like that of most of the other aromatic oils) is cordial, stimulant, and stomachic. A few drops (10 to 30) on sugar, or mixed with a little water or wine, is an excellent remedy in flatulence, colic, nausea, sickness, &c. It is also extensively used as a flavouring ingredient by cooks, confectioners, and druggists. A few drops, well agitated with half a pint of cold water, form an excellent extemporaneous peppermint water.

The formulæ 1 and 2, generally the latter, are those employed by the respectable portion of the London trade. The various published receipts for this and similar essences, ordering the essential oil in a larger proportion than that directed above, are never adopted in practice, and their products (often impossible combinations) exist only in the imaginations of the writers.

=Essence of Pimen'to.= See ESSENCE OF ALLSPICE.

=Essence of Pine-apple.= From pine-apple oil (butyric ether, butyrate of ethyl), as ESSENCE OF ALMONDS. It forms a delicious flavouring for liqueurs, confectionery, rum, &c. See ETHER and OIL (Volatile).

=Essence of Quas'sia.= _Syn._ ESSENTIA QUASSIÆ, L. _Prep._ 1. From quassia (sliced), 1-1/2 oz.; proof spirit, 1 pint; digest 10 days, and filter; 1/2 fl. dr. added to 7-1/2 fl. dr. of water, forms the infusion of quassia, of the Ph. L.--_Dose_, 1/2 dr. in water or wine, an hour before a meal, as a stomachic tonic, in dyspepsia, loss of appetite, &c., particularly when complicated with gout; 1 to 2 dr., three or four times daily, as a febrifuge, and antiseptic, in intermittents, putrid fevers, &c.

2. (Brewer's).--_a._ From powdered quassia (sprinkled with a little rum) and "foots" (coarse moist sugar or sugar bottoms), equal parts, reduced to the consistence of a semi-fluid extract by the addition of a few spoonfuls of water. For ale.

_b._ From powdered quassia, 1 part; burnt sugar colouring, 2 parts; well stirred together. For porter and stout. Both are used by fraudulent brewers as substitutes for hops.

=Essence of Quin'ine.= _Syn._ ESSENTIA QUINÆ, L. _Prep._ From disulphate of quinine, 1-1/2 oz.; rectified spirit, 1/2 pint; digest with warmth, gradually dropping in a little dilute sulphuric acid (avoiding excess), and employing constant agitation until the whole is dissolved. 1 fl. dr., added to 7 dr. of proof spirit, forms the 'TINCTURE OF QUININE' (Ph. L.). Every fl. dr. contains 8 gr. of disulphate of quinine, or about 10 gr. of the neutral sulphate. If more sulphuric acid is added than is sufficient to dissolve the salt (_i. e._ convert it into a neutral sulphate), the solution is apt to deposit part of it on keeping, owing to the gradual formation of ether, by the action of the excess of acid on the alcohol.

=Essence of Rat'afia.= The same as Essence of Almonds. So called from being used to flavour ratafias, noyeau, and other liqueurs.

=Essence of Rhu'barb.= _Syn._ ESSENTIA RHEI, L. _Prep._ From rhubarb (in powder) and siliceous sand, of each 5 oz.; proof spirit, 1 pint; by the method of displacement. Every fl. oz. represents the active virtues of 2 dr. of rhubarb.

=Essence of Rondele'tia.= _Prep._ 1. Essence (oil) of bergamotte, essence (oil) of lemon, and oil of cloves, of each 1 dr.; otto of roses, 10 drops; rectified spirit, 1 pint.

2. To the last add, of oil of lavender, 1 dr.; neroli, 15 drops. A very fashionable and agreeable perfume.

=Essence of Rose'mary.= _Syn._ ESSENTIA ROSEMARINI, L. _Prep._ From oil of rosemary, as ESSENCE OF ALLSPICE. Used as a perfume; also to make extemporaneous rosemary water.

=Essence of Ro'ses.= _Syn._ ESSENTIA ROSÆ (ODORATA), L. _Prep._ 1. Attar of roses (genuine), 2 dr.; alcohol, 1 pint; agitate frequently until they unite.

2. Attar of roses, 1 oz.; rectified spirit, 1 gall.; mix in a close vessel, and assist the solution by placing it in a bath of hot water. (See ESSENCE OF MUSK.) As soon as the spirit gets warm, take it from the water and shake it till quite cold; the next day filter.--_Obs._ Unless the spirit of wine is of more than the common strength, it will not retain the whole of the otto in solution in very cold weather.

3. To each pint of either of the preceding, add, of oil of bergamotte, 30 drops; neroli and essence of musk, of each 20 drops.

4. Petals of roses, 3 lbs., digest in spirit of wine, 5 quarts, for 24 hours; distil to dryness in a water bath; digest the distilled spirit on 2 lbs. of fresh rose petals, as before, and repeat the whole process of maceration and distillation, a third, fourth, fifth, and sixth time, or oftener, the last time only drawing over 1 gall., which is the essence. Each of the above is very superior. The last has a peculiar delicacy of flavour, when the spirit used to make it is pure.

=Essence of Roses (Red).= _Syn._ ESSENTIA ROSÆ (RUBRA), TINCTURA E. CONCENTRATA, L. _Prep._ From rose leaves, 1 lb.; proof spirit, 1 gall.; digest for 14 days, press, strain, add concentrated acetic acid, 2-1/2 fl. dr.; mix well, and the next day filter. Used to make extemporaneous SYRUP and HONEY OF ROSES, &c. Smells, colours, and tastes strongly of the flower. CONCENTRATED INFUSION OF ROSES is sold under the same name.

=Essence Royale.= [Fr.] _Prep._ 1. (Soubeiran.) Ambergris, 40 gr.; musk, 20 gr.; civet and carbonate of potassa, of each 10 gr.; oil of cinnamon, 6 drops; oil of rhodium and otto of roses, of each 4 drops; rectified spirit of wine, 4 fl. oz. (say 1/4 pint); macerate for 10 days or longer. Antispasmodic and aphrodisiac. A few drops on sugar, or in syrup of capillaire.

2. See ESSENCE OF AMBERGRIS.

=Essence of Sarsaparil'la.= _Syn._ CONCENTRATED ESSENCE OF SARSAPARILLA; ESSENTIA SARSÆ; E. SARSAPARILLÆ; L. _Prep._ 1. Sarsaparilla root (best red Jamaica), 2-3/4 lbs., is carefully decorticated, the bark reduced to coarse powder, and digested for a week or 10 days in sherry, 3/4 pint, and rectified spirit, 1/4 pint, with frequent agitation; after which the essence is expressed, and in a week the clear portion is decanted from the sediment. A very elegant preparation. 1/2 fl. dr. added to 7 fl. dr. of water forms 1 fl. oz. of a solution of equal strength to decoction of sarsaparilla of the Ph. L. Every fl. oz. represents the active principles of 2 oz. (= 2 oz. 85 gr. avoir.) of sarsaparilla root. In other words, it is twice as strong as the root, and 16 times as strong as the decoction.

2. Alcoholic extract of sarsaparilla, 7 oz.; sherry, 3/4 pint; rectified spirit, 1/4 pint; dissolve and filter. Strength as the last.

3. (Beral.) Alcohol extract, 4 oz.; sherry wine, 1 pint; dissolve and filter. About 3 fl. dr., added to water, 1 pint, form an extemporaneous decoction.

4. (Guibourt.) Alcoholic extract, 4 oz.; white wine, 1 lb. Strength the same as Nos. 1 and 2 (nearly).

5. (Hening.) Sarsaparilla (bruised), 10 oz.; distilled water, 6 pints; macerate at a temperature of 120° Fahr. for six hours and strain; repeat with the same quantity of fresh water; mix the liquors, and evaporate in china vessels at 160° Fahr. If reduced to 10 fl. oz. (or to 9 fl. oz., with 1 fl. oz. of rectified spirit added), 1 fl. dr., mixed with 7 fl. dr. of water, will be equal to the decoction of the usual strength. If reduced to 5 fl. oz. 1 fl. dr. will be equal to 2 fl. oz. of the decoction.

6. The bark separated from sarsaparilla root, 2-3/4 lbs., is exhausted with water as last; the liquid is evaporated as quickly as possible, in a water bath, to 16 fl. oz., and when cold, mixed with rectified spirit, 4 fl. oz. Strength same as No. 1.

7. The infusion in No. 6 is evaporated to 10-1/2 fl. oz., and when cold mixed with sherry, 1/2 pint; in a week the clear portion is decanted from the sediment. Strength same as No. 1.

_Obs._ The formulæ Nos. 1, 2, 6, and 7 have each in turn been extensively employed by us in the laboratory with the most satisfactory results. See LIQUOR OF SARSAPARILLA.

=Essence of Sarsaparilla (Compound).= _Syn._ ESSENTIA SARSAPARILLÆ COMPOSITA, E. SARSÆ C., L. _Prep._ 1. One pint of No. 1, 2, 6, or 7 (_above_), is triturated with the extract prepared from mezereon bark, 3-1/4 oz., and extract of liquorice, 4 oz.; when mixed it is returned to the bottle, and essence of guaiacum, 1-1/2 fl. dr., and oil of sassafras, 20 drops, are added, the whole is then well agitated for at least 15 minutes, and after a week's repose the clear portion is decanted as before. 1/2 fl. dr., with 7-1/2 fl. dr. of water, forms extemporaneous compound decoction of sarsaparilla.

2. (Cadet.) Sarsaparilla (bruised), 8 oz.; hot water, q. s.; exhaust the root by successive macerations; unite the liquors, and evaporate to 10 fl. oz.; strain, and add, when cold, of alcohol (·842) and tinctures of guaiacum and mezereon, of each 4 fl. dr.; white wine, 1 fl. oz.; oil of sassafras, 12 drops; extract of liquorice, 2 dr.; agitate, and after repose decant as before. This is nearly 8 times as strong as 'DEC. SARSÆ CO.'--Ph. L. The first is the best formula. See LIQUOR OF SARSAPARILLA (Compound).

=Essence of Sa''vory Spices.= _Prep._ 1. Black pepper, 4 oz.; powdered turmeric, 3 dr.; coriander seeds, 1-1/2 dr. (all ground and genuine); oil of pimento, 1-1/2 fl. dr.; oils of nutmeg, cloves, cassia and caraway, of each 1/2 dr.; rectified spirit, 1 pint; digest, with agitation, for a fortnight. Very fine.

2. Black pepper, 3 oz.; allspice, 1-1/4 oz.; nutmegs and burnt sugar, of each 1/2 oz.; cloves, cassia, coriander, and caraway seeds, of each 1 dr. (all bruised or ground); rectified spirit, 1 pint; digest with agitation, as before, for 14 days, press, and filter. Used as a flavouring. When made with proof spirit or brandy, and only 1/2 the above weight of spice, it is called 'TINCTURE OF SAVORY SPICES,'

=Essence of Sen'na.= See LIQUOR and INFUSION (Concentrated).

=Essence of Smoke.= See ESSENCE, WESTPHALIAN.

=Essence of Soap.= _Syn._ SPIRIT OF SOAP, SHAVING FLUID; ESPRIT DE SAVON, ESSENCE DE SAVON, ESSENCE ROYALE POUR FAIRE LA BARBE, Fr.; ESSENTIA SAPONIS, TINCTURA SAPONIS CONCENTRATA, L. _Prep._ 1. Castile soap (in shavings), 4 oz.; proof spirit, 1 pint; dissolve, and add a little perfume.

2. Venetian soap, 3/4 lb.; salt of tartar, 1 oz.; benzoin, 1/2 oz.; spirit of wine, 1 gall.

3. Best soft soap, 1/4 lb.; boiling water, 1 pint; dissolve, cool, and add, oils of cinnamon (cassia), verbena, and neroli, of each 6 drops; dissolved in rectified spirit, 1 pint; mix well, and if not perfectly transparent, add a little more strong spirit, or filter through blotting paper.

_Obs._ This alcoholic solution of soap is chiefly used for shaving, and is very convenient in travelling, as a good lather may be instantly produced without the trouble of employing a soap-box. Instead of the above perfumes, 15 drops of essence of musk or ambergris, or 30 drops of any of the perfumed spirits, or 3 drops of attar of roses, or 6 drops of any of the aromatic essential oils, may be added, when a corresponding name is given to the preparation, as esprit de savon, de la rose, &c.

4. (P. Cod.) White soap, 3 oz.; carbonate of potassa, 1 dr.; proof spirit, 12 oz.; dissolve. Used medicinally. They are all used as frictions, &c.

5. (CAMPHORATED,--Guibourt.) White soap, 3 parts; camphor, 1 part; spirit of rosemary, 16 parts; dissolve. A variety of opodeldoc. Used as an embrocation in rheumatic pains, sore throat, &c.

=Essence of Soup Herbs.= _Syn._ SPIRIT OF SOUP HERBS, CONC. TINCTURE OF S. H., &c. _Prep._ (Kitchener's.) Lemon thyme, winter savory, sweet marjoram, and sweet bazil, of each 1 oz.; lemon peel (grated), and eschalots, of each 1/2 oz.; bruised celery seed, 1/4 oz.; proof spirit or brandy, 1 pint; digest for 10 days or a fortnight. A superior flavouring essence for soups, gravies, &c. See ESSENCE OF SAVOURY SPICES.

=Essence of Spear'mint.= See ESSENCE OF MINT.

=Essence of Sprats.= _Syn._ ESSENCE OF BRITISH ANCHOVIES. From pickled sprats (British anchovies), as ESSENCE OF ANCHOVIES, for which it is commonly sold.

=Essence of Spruce.= _Syn._ FLUID EXTRACT OF SPRUCE; ESSENTIA ABIETIS, EXTRACTUM A. FLUIDUM, L. _Prep._ A decoction of the young tops of the black spruce-fir _Abies nigra_, evaporated to the consistence of a thick syrup. Used to make spruce beer, &c.

=Essence, Toothache.= _Syn._ ESSENTIA ODONTALGIA, L. _Prep._ 1. Acetate of morphia, 1/2 dr.; tincture of pellitory of Spain (made with rectified spirit), 2 fl. oz.; acetic acid (glacial), 4 fl. dr.; dissolve, and add of oil of cloves, 6 fl. dr.

2. (Redwood.) Pellitory, 1/2 lb.; extract of belladonna, 2 dr.; rectified spirit, 1 pint; digest 14 days, strain, and add, of hyponitrous ether, 1 oz.; oil of wine, 1/2 oz.; oil of cloves, 2 dr. See DROPS (Odontalgic).

=Essence of Tu''berose.= _Prep._ The flowers are stratified with sheep's or cotton wool, impregnated with the purest oil of ben or of olives, in an earthen vessel, closely covered, and kept for 12 hours in a water bath; the flowers are then removed, and fresh ones substituted, and this is repeated until the oil (HUILE AU TUBEROSE) is sufficiently scented. The wool or cotton is then mixed with the purest spirit of wine, and distilled in a water bath; or it is first digested in a warm situation, and in a well-closed vessel, for several days, during the whole of which time frequent agitation is had recourse to. A similar plan is followed for the preparation of essences of jasmine, violets, and other like flowers. See SPIRIT.

=Essence of Turtle.= _Syn._ ESSENCE OF GREEN TURTLE. _Prep._ From essence of anchovies and shallot wine, of each 3 oz.; basil wine, 1/2 pint; mushroom ketchup, 1/4 pint; the juice of 2 lemons; the yellow peel of 1 lemon; curry powder, 1/4 oz.; digest for a week. Used to impart the flavour of turtle to soups and gravies.

=Essence of Tyre.= See HAIR DYE.

=Essence of Vanil'la.= _Syn._ ESSENTIA VANILLÆ, TINCTURE V. CONCENTRATA, L. _Prep._ 1. Vanilla (cut small), 2 oz.; rectified spirit, 1 pint, digest a fortnight.

2. (Wholesale.) Vanilla, 2 lbs.; rectified spirit, 1 gall.; proceed as for ESSENCE OF MUSK. Very superior.

3. Vanilla (best), 3/4 lb.; spirit of ambrette, 1 quart; cloves, 30 gr.; grain musk, 7 gr.; as last. Much esteemed. It is chiefly used as a perfume and for flavouring.

=Essence of Verbe'na.= _Syn._ ESSENCE OF LEMON-GRASS, E. OF CITRONELLE; ESSENTIA VERBENÆ, L. _Prep._ 1. From oil of lemon-grass or verbena (_Andropogon citratum_), as ESSENCE OF ALLSPICE.

2. To the last add, of essences of ambergris and bergamotte (oil), of each 1 fl. dr.; neroli, 1/2 fl. dr.

3. To No. 1. add, of oils of lavender and bergamotte, of each 1/2 dr.; essence of vanilla, 2 fl. dr. A powerful and refreshing perfume.

=Essence of Vio'let.= _Syn._ ESSENTIA VIOLÆ, L.; ESSENCES DES VIOLETTES, Fr. See ESSENCE OF TUBEROSE and SPIRIT.

=Essence of Vittie Vayr.= _Syn._ ESSENCE OF VETIVER; ESSENCE DE VITTIE VAYR DOUBLE, Fr. _Prep._ 1. Vittie vayr or cuscus (the root of _Andropogon muricatus_, cut small and bruised), 3 lbs.; proof spirit, 9 pints; digest a week, add of water, 5 pints, and the next day distil over 1 gall. of essence.

2. To the last, before distillation, add, of otto of roses, 1/2 dr.; eau de melisse (spirit of balm), 1/2 pint; and proceed as before. Used as a perfume. In 1831 it was much employed in Paris as a prophylactic of cholera.

=Essence, Volatile (Acetic).= _Syn._ PUNGENT ACETIC ESSENCE; ESSENTIA VOLATILIS ACETICA, L. Aromatic vinegar.

=Essence, Volatile (Ammoniacal).= _Syn._ PUNGENT AMMONIACAL ESSENCE, AROMATIC AMMONIACAL E.; ESSENTIA VOLATILIS, E. V. AMMONIACALIS, E. V. AROMATICA, &c., L. _Prep._ 1. Oil of cinnamon, 6 drops; otto of roses, 12 drops; oil of cloves, 1 fl. dr.; essence of bergamotte, 2 fl. dr.; oil of lavender (Mitcham), 4 fl. dr.; essence of musk, 5 fl. dr.; liquor of ammonia (strongest), 1 pint; mix in a cold place, and shake the bottle until the whole is combined.

2. Essence of violets and oil of cinnamon, of each 12 drops; neroli, essence of jasmine, and otto of roses, of each 1/2 dr.; oil of lavender, 1 dr.; essence royale and essence (oil) of bergamotte, of each 2-1/2 dr.; liquor of ammonia (strongest), 1 pint; as the last.

3. Oils of lemon and bergamotte, of each 5 fl. dr.; oil of lavender, 1-1/2 fl. dr.; otto of roses, 1 fl. dr.; oils of cassia, neroli, cloves, and cedrat, of each 1/2 fl. dr.; oil of sandal wood, 15 drops; liquor of ammonia (strongest), 1 pint.

4. Essence of bergamotte, 6 fl. dr.; oil of lavender, 4 fl. dr.; oil of cloves, 3 fl. dr.; oil of cassia, 1-1/2 fl. dr.; oil of verbena (lemon-grass), 1 fl. dr.; otto of roses, 30 drops; liquor of ammonia, 18 fl. oz.

5. (Redwood.) Oil of bergamotte, 3 oz.; essence of lemons, 2 oz.; oil of lavender, 6 dr.; essence of jasmine, 4 dr.; oil of sassafras, 3 dr.; oil of neroli, 2 dr.; otto of roses, 1-1/2 dr.; oil of origanum and essence of ambergris, of each 1 dr.; musk, 20 gr.; macerate for a week, and decant the clear portion. It is added to the strongest liquor of ammonia in proportion of 1-1/2 oz. to the pint.

_Obs._ The above are used to fill smelling-bottles. They are all very fragrant and refreshing.

=Essence, Ward's.= See ESSENCE HEADACHE.

=Essence of Water-fen'nel.= _Syn._ ESSENTIA PHELLANDRI AQUATICI, E. F[OE]NICULIS A., L. _Prep._ (Cottereau.) Water-fennel seeds (fine-leaved water-hemlock, bruised), 1 oz.; proof spirit, 4 fl. oz.; digest. Narcotic and pectoral.--_Dose_, 5 to 25 drops, combined with bark; in phthisis, &c.

=Essence, Westphalian.= ESSENCE OF SMOKE, E. OF WOOD-SMOKE, CAMBRIAN ESSENCE, SMOKING FLUID; ESSENTIA FULIGINIS, &c., L. _Prep._ 1. Crude or empyreumatic pyroligneous acid, 1 pint; sugar colouring, 2 oz.; dissolve, and in a week decant the clear portion.

2. Tar, 3 dr.; sugar colouring, 2 oz.; hot crude pyroligneous acid, 1 pint; agitate constantly for 1 hour, and after repose decant the clear portion.

3. Acetic acid (Ph. L.), 1 pint; creasote, 5 dr.; mix. White.

4. Barbadoes tar, 1/4 oz.; burnt sugar and common salt, of each 1 oz.; strong pickling vinegar, 3/4 pint; port or elder wine, 1/4 pint; digest as before. Inferior to the preceding. Used to impart a smoky flavour to meat, fish, &c., by brushing it over them, or adding a little to the brine in which they are pickled.

=Essence of Worm'wood.= _Syn._ ESSENTIA AMARA, E. ABSINTHII, L. _Prep._ 1. Extract of wormwood, 4 oz.; oil of wormwood, 1 oz.; rectified spirit, 1 pint; digest a week and filter. Tonic, stomachic, and vermifuge.--_Dose_, 10 drops to a teaspoonful.

2. (Van Mons.) Tincture of wormwood, 1 pint; salt of wormwood, 5 dr.; extract of wormwood, 1 dr.; digest as before.--_Dose_, 1/2 to 1-1/2 fl. dr.

=Essences, Fla''vouring.= _Syn._ CULINARY ESSENCES, SPICE E., ESSENCES FOR THE TABLE, &c. Those used by cooks, confectioners, liqueurists, &c., are all made by either dissolving 1 fl. oz. of the essential oil of the particular substance in 1 pint of rectified spirit, or by digesting 4 to 6 oz. of the bruised spice, or 5 to 10 oz. of the dried herb, in a like quantity (1 pint) of spirit. The first method is preferable, from being the least troublesome, and yielding the finest product. They are commonly labelled 'CONCENTRATED ESSENCE OF ----.' An inferior article, vended under the names of 'ESSENCES OF CULINARY HERBS,' 'CULINARY TINCTURES,' 'TINCTURES FOR KITCHEN USE,' &c., are prepared from half the above quantity of oil or spice, infused in a pint of proof spirit or British brandy. The principal compounds of this class are the essences of allspice, caraway, cardamoms, cassia, cayenne, celery seed, cinnamon, cloves, coriander seed, fennel, garlic, ginger, lemon peel, mace, marjoram, nutmegs, orange peel, peppermint, spearmint, sweet basil, and the like. The whole of these are employed to flavour soups, gravies, sweetmeats, pastry, wines, mulled wines, liqueurs, &c.

=Essences, Flower.= Those for which separate formulæ are not given in this work may most of them be made from the essential oil of the flowers and rectified spirit, as the last; or by digesting the flowers (crushed or bruised), 3 to 5 lbs., in proof spirit, 2 galls., for a few days, and then drawing over, by distillation, 1 gall. For the essences of those flowers which are not strongly odorous, the spirit thus obtained is distilled from a like quantity of flowers, a second, and a third time, or even oftener. The essences of other organic substances, whose fragrant principles are volatile, may be prepared in the same manner. A small quantity of some other odorous essence is frequently added to the product, to enrich or modify the fragrance. See FLOWERS and ESSENCES BY INFUSION.

=Essences, Fra'grant.= See FLOWER ESSENCES (_above_), ESSENTIA ODORATA, PERFUMERY, &c.

=Essences, Fruit.= See ESSENCES OF APPLE, PINE-APPLE, JARGONELLE, &c.

=Essences by Infu'sion.= This term, among perfumers, is commonly applied to those essences, eaux, and esprits, which are prepared by digesting the ingredients in the spirit used as the vehicle for the aroma, in opposition to those obtained by 'distillation,' or by 'contact,' or 'pressure.' Thus, the ESSENCES OF AMBERGRIS, MUSK, and VANILLA, are of this class.

=Essences, Vi'nous.= _Syn._ ESSENTIA VINOSA, L. These are prepared in a similar way to the wines (VINA) of the pharmacop[oe]ia, by using 8 times the usual quantity of ingredients, and the very strongest sherry wine. 1 fl. dr., added to 7 fl. dr. of wine or water (properly the first only), forms an extemporaneous imitation of the officinal VINA MEDICATA. Some of the above are largely used in dispensing, and by travellers. See LIQUOR and WINE.

=ESSENTIA BI'NA.= See COLOURING.

=Essentia, Odora'ta.= _Prep._ 1. Oil of lavender, 1 dr.; oils of cloves, cassia, and bergamot, of each 1/2 dr.; neroli, 20 drops; essence royale, 2 fl. dr.; rectified spirit, 1/2 pint; mix.

2. (Redwood.) English oil of lavender, 48 drops; oil of cloves, 32 drops; oil of orange peel, 16 drops; oil of bergamotte and sweet spirit of nitre, of each 8 drops; oil of yellow sandal-wood, neroli, and otto of roses, of each 2 drops; oil of cinnamon, 1 drop; rectified spirit, and essence of ambergris and musk, of each 1 oz.; honey water, 8 oz.; mix. Used as a perfume for the handkerchief, &c. The last form seems unnecessarily complicated and minute.

=Essentia Odorif'era.= _Prep._ 1. Grain musk and balsam of Peru, of each 10 gr.; civet, 4 gr.; oil of cloves, 5 drops; oil of rhodium, 3 drops; salt of tartar (dried by a dull-red heat and cooled), 1/2 dr.; rectified spirit (strongest), 2-1/2 fl. oz.; macerate for 14 days, and pour off the clear.

2. Oil of rhodium and balsam of Peru, of each 1/2 dr.; oil of cloves, 1 dr.; spirit of ammonia, 2 fl. dr.; essence of civet and vanilla, of each 2 fl. oz.; essence of musk, 5 fl. oz.; neroli, oils of lavender, verbena, and cassia, of each 6 drops. As last. Both are very pleasant, durable, and powerful perfumes for personal use.

=ESSENTIAL OIL.= See OIL (Volatile).

=ESSENTIAL SALT OF BARK.= See BARK and =Extract=.

=ESSENTIAL SALT OF LEMONS.= _Syn._ SALT OF LEMONS; SAL LIMONUM, L. The preparation sold under this name is made by mixing cream of tartar (bitartrate of potassa) with twice its weight of salt of sorrel (quadroxalate of potassa), both in fine powder. It is used to remove fruit stains, &c., from linen, by rubbing a little of it on the part moistened with warm water. It is poisonous, if swallowed in quantity.

=ETCH'ING.= A species of engraving, in which the design is formed on the plate by the action of an acid, or some other fluid, instead of being cut out by the graver.

_Proc._ In the ORDINARY PROCESS OF ETCHING the plate is covered with 'etching ground' (an acid-resisting varnish), and the design is scratched on the metal through the ground, by means of a pointed tool of steel called the 'etching needle' or 'point.' A border of wax is then placed round the plate, and the 'biting' fluid poured on, and allowed to remain till the 'lights' or finest portions of the design are sufficiently 'bitten in,' The etching fluid is then poured off, the plate washed, and the light parts 'stopped out' with Brunswick black or other varnish; the solvent is again poured on, and allowed to remain until the finest portion of the exposed lines are sufficiently deep, when the acid is again poured off, and the whole process is repeated till the very darkest lines or shadows are sufficiently 'bitten in,' The plate is then cleaned, and is ready to be printed from. Occasionally the etched design receives a few finishing touches with the 'graver.'

There are several varieties of etching, of which the following are the principal:--ETCHING WITH A SOFT GROUND, when a coating of lard or tallow is employed, and the design is drawn on a piece of paper, laid evenly on the ground, by which means the fatty matter adheres to the paper, on the parts pressed on by the point or pencil, and the copper beneath becomes exposed, and is then acted on by the acid. The effect resembles that of chalk or pencil drawings.--STIPPLING, or executing the design in dots instead of lines.--AQUATINTA or AQUATINT, a mode of etching on copper for producing an effect resembling a drawing in Indian ink. It is performed by sifting powdered asphaltum or lac resin on the plate, previously slightly greased, and, after shaking off the loose powder, gently heating it over a chafing dish; on cooling, the lights are covered with turpentine varnish coloured with lampblack, by means of a hair pencil, and a rim of wax being placed round the plate, a mixture of 'aquafortis' and water is poured on it, and allowed to remain for 5 or 6 minutes, when it is poured off, the plate dried, and recourse had to the pencil as before. The process of 'stopping' and 'etching' is repeated again and again, until the darkest shades are produced. Sometimes, instead of using asphaltum, an alcoholic solution of shell-lac or gum mastic is poured over the plate, placed in a slanting direction; this varnish forms a film, which, on drying, leaves innumerable cracks or minute fissures through which the acid acts on the plate. The fineness or coarseness of the grain depends entirely upon the condition of the powdered asphaltum, or on the quantity of matter dissolved in the spirit employed to form the ground.

The fluids employed for 'biting in' the designs vary considerably, almost every artist having his own receipt. Aquafortis, more or less diluted, is, however, generally employed for COPPER, and this, with the addition of pyroligneous acid, for etching on STEEL; but any fluid that rapidly dissolves the metal may be used for the purpose. The 'etching ground' may be formed of any substance capable of resisting the action of the etching fluid, and which is, at the same time, sufficiently soft to allow of the free use of the needle or point, and sufficiently solid to prevent an injury to the design during the 'scratching in,'

In ETCHING ON GLASS, the ground is laid on, and the design 'scratched in' in the usual way, when liquid hydrofluoric acid is applied, or the glass is exposed to the action of hydrofluoric acid gas. The former renders the surface of the etching transparent, the latter opaque. A simple modification of the process is to wet the design with sulphuric acid, and then to sprinkle on some finely pulverised fluor spar (fluoride of calcium), by which means hydrofluoric acid is set free and attacks the glass. This method may be very easily applied to the graduation of glass vessels, thermometer tubes, &c.

ETCHING ON GLASS BY ELECTRICITY. Planté ('Ann. Chem. Phys.' [5], xiii, 143-144). The author had previously drawn attention to the fact that when an electric current is passed through saline solutions in glass vessels, platinum wire serving as electrodes, the glass is immediately attacked, and he therefore proposes the following method for etching on glass:

The surface of the glass to be engraved is coated with a concentrated solution of potassium nitrate, and beneath the layer of liquid a platinum wire, connected with one of the poles of a battery, is stretched across the plate. With the other pole is connected another platinum wire, the whole of which, except the point, is insulated; with this the designs are drawn on the glass, which is engraved wherever the wire comes in contact with it, flashes of light being emitted at the same time.

The depth of engraving depends on the rate at which the platinum wire moves; the slower the rate the deeper the line.

A RAPID METHOD OF ETCHING ON IRON OR STEEL, capable of very general application, is as follows:--"The metal is warmed until it is capable of melting a piece of beeswax, or 'etching ground,' which is then carefully rubbed over it, so as to form a thin and even coating; when cold, the design is 'scratched in' in the common way; a little powdered iodine is then sprinkled on the exposed parts, and at the same time a few drops of water are added, and the two worked into a liquid paste with a camel-hair pencil. The paste is then moved about over the intended etching, for a period varying from one to five minutes, according to the depth of the lines required to be produced. Afterwards the whole is removed, and reapplied, &c., as with the usual etching fluids. The same etching-paste, by being kept for a few days, again acquires the property of dissolving iron, and may be used again and again; but independently of this, the iodide of iron formed during the process, if rapidly evaporated to dryness in a clean iron vessel by a moderate heat, and placed in stoppered bottles, will sell for more than the original cost of the iodine. To travellers and amateurs who amuse themselves with the delightful art of etching, iodine, from its portability and convenience, will, doubtless, prove invaluable. We have adopted it with considerable success, and have found it especially useful in marking surgical instruments, razors, and other edge tools. We published this method many years ago. Several parties have since availed themselves of our suggestions and formulæ, but without the slightest acknowledgment of the source from which they obtained them." (A. J. Cooley.)

=Etching, Electro-.= This mode of etching, which is in many respects superior to the ordinary mode, is based upon the destructive action of certain 'anions' during 'electrolysis.'[281] If two plates of copper be connected with the opposite ends of a voltaic battery, and placed in a vessel containing very dilute sulphuric acid, the plate connected with the copper of the battery will be attacked by the anion oxygen which is released during the decomposition of the acid. This destructive action can be localised at pleasure by covering certain parts of the plate with a protecting stratum of varnish, ordinary 'etching ground' for instance. In the practice of electro-etching, the drawing is 'scratched in' in the usual way through an ordinary ground; a stout wire is then soldered to the plate, and this, as well as the back of the plate, is coated with sealing-wax varnish. Thus prepared, the plate is placed in a suitable 'decomposition cell' opposite a plate of somewhat similar size, and the two are connected respectively with the copper and zinc of a 'Daniell's cell,' or the silver and zinc of a 'Smee's cell.'[282] After about ten minutes the plate is removed, washed, and dried; and when the 'fine work' has been stopped out with Brunswick black, it is returned for another space of ten minutes. By alternately exposing the plate to the action of the decomposing fluid, and 'stopping out' parts of the work, the required gradation in tints is obtained. The exact duration of the various exposures, as well as their number, must, of course, be regulated by circumstances. See ETCHING FLUIDS (_below_).

[Footnote 281: See ELECTROLYSIS and ELECTROTYPE, pages 428 and 429.]

[Footnote 282: See VOLTAIC ELECTRICITY.]

=Etching Fluids.= 1. (For COPPER.)--_a._ From 'aquafortis,' 2-1/2 fl. oz.; water, 5 fl. oz.; mix.

_b._ To the last add of verdigris, 1 oz.; water, 2-1/2 fl. oz.; dissolve. For light touches.

_c._ (EAU FORTE,--Callot and Piranesi.) Alum, sal-ammoniac, sea salt, and verdigris, of each 4 oz.; vinegar (pyroligneous acid), 8 fl. oz.; water, 16 fl. oz.; mix, dissolve, boil for 1 or 2 minutes in a glazed or stoneware vessel, cool, and decant the clear portion. Used as the last.

_d._ Water acidulated with sulphuric acid. Used in the process of electro-etching.

2. (For STEEL.)--_a._ From iodine, 1 oz.; iron filings or wire, 1/2 dr.; water, 4 fl. oz. It must be kept in a stoppered bottle, until required for use.

_b._ From iodine, 3 dr.; iodide of potassium, 1 dr.; proof spirit, 1 fl. oz.; water, 2 fl. oz. As the last.

_c._ (Mr Turrel.) Pyroligneous acid, 4 fl. oz.; alcohol (rectified spirit), 1 fl. oz.; mix, and add of nitric acid or double aquafortis (sp. gr. 1·28), 1 fl. oz.

_d._ From hydrochloric acid, 5 parts; water, 95 parts; mix, and add the liquid to a solution of chlorate of potassa, 1 part, in water, 50 parts.

_e._ A solution of common salt. Used in the process of electro-etching.

=Etching Ground.= _Syn._ ETCHING VARNISH. _Prep._ 1. Beeswax, 5 parts; linseed oil, 1 part; melted together.

2. (Callot's HARD VARNISH, FLORENTINE V., FLORENCE V.) From linseed oil and mastic, equal parts, melted together.

3. (Callot's SOFT VARNISH.) From linseed oil, 4 oz.; gum benzoin and white wax, of each 1/2 oz.; boil to two thirds.

4. (Lawrence.) White wax, 2 oz.; black pitch and Burgundy pitch, of each 1/2 oz.; melt, add by degrees, of powdered asphaltum, 2 oz.; and boil together, until a piece, when thoroughly cold, will break by being bent double 2 or 3 times between the fingers; next pour it into warm water, make it into small balls, and place each of them in a piece of taffety for use.

_Obs._ The preceding compositions are applied to the surface of the plates, previously made sufficiently warm to melt them easily, their even diffusion being promoted by dabbing them with a wad of cotton. Those that are white are then generally blackened on the surface by skilfully passing them over the smoky flame of one or more candles, by which the marks of the etching point on the bright metal are rendered the more visible.

=E'THER.= _Syn._ OXIDE OF ETHYL. Described under ETHYL, OXIDE OF. Several substances are known under the name of ethers besides the true ethers or salts of ethyl, and are given below.

=Ether of Canthar'ides.= _Syn._ ÆTHER CANTHARIDALIS, L. _Prep._ ([OE]ttinger.) From powdered cantharides, 1 part; ether, 2 parts; digested together for 3 or 4 days, and the tincture expressed. Used as a vesicant, &c.

=Ether, Chlo''ric.= This name was applied by Dr T. Thomson to the CHLORIDE OF OLEFIANT GAS, or 'DUTCH LIQUID,' and afterwards, by Guthrie and Silliman, to CHLOROFORM, which they took for an alcoholic solution of chloride of olefiant gas. It now forms one of the synonyms of chloroform. The medicinal 'CHLORIC ETHER' of the shops is a solution of chloroform, 1 part, in rectified spirit 8 parts; of which the _dose_ is 20 or 30 drops in water, as an antispasmodic and anodyne. See CHLOROFORM.

=Ether, Chlorinet'ted.= Formed by the action of dry chlorine on pure ether. When the action is long continued, a heavy, oily product (BICHLORINETTED ETHER), smelling like fennel, is formed. By the still further action of chlorine, aided by sunlight, a white, crystalline substance (PENTACHLORINETTED ETHER), a compound resembling sesquichloride of carbon, is obtained.

=Ether, Cu''preous.= _Syn._ TINCTURA CUPRI CHLORIDI ÆTHEREA, L. _Prep._ (Van Mons.) Sulphate of copper, 6 parts, and chloride of barium, 5 parts, are triturated together, and the mixture digested in ether, 3 or 4 parts, until all the chloride of copper is dissolved.--_Dose_, 2 to 5 drops; in epilepsy, &c.

=Ether, Methy'lic.= _Syn._ OXIDE OF METHYL, WOOD-ETHER, METHYL-ETHER; ÆTHER METHYLICUS, L. _Prep._ From wood spirit, 1 part; concentrated sulphuric acid, 4 parts; mix in a retort, apply heat, pass the evolved gas (methylic ether) through a little strong solution of potassa, and then collect it over mercury. See METHYL.

=Ether, Spirits of Nitrous.= See SPIRITS.

=Ether, Washed.= _Syn._ ÆTHER LOTUS, L. Ordinary ether, agitated first with 2 or 3 times its volume of distilled water, and a few grains of carbonate of potassa, or a few drops of milk of lime; and after decantation, again agitated with a like quantity of water only. Used for inhalations. For other purposes the washed ether is afterwards digested on chloride of calcium, to deprive it of retained water.

=E'THERIN.= _Syn._ CAMPHOR OF OIL OF WINE. A volatile, white, crystalline substance, deposited by light oil of wine when left in a cold situation for some time. It is isomeric with etherole, and received its name from the assumption of its being the base of the ethereal compounds. According to this hypothesis, ether is a hydrate of etherin. Etherin forms brilliant prisms and plates; is tasteless; soluble in alcohol and ether; fuses at 230° Fahr., and boils at 500° Fahr.; and is a little lighter than water. The crystals are purified by pressure between the folds of bibulous paper, solution in ether, and evaporation.

=E'THEROLE.= The yellowish, oily liquid, forming the residual portion of light oil of wine, after it has deposited its etherin. It is lighter than water; is freely soluble in both alcohol and ether; and has a rather high boiling-point. See ETHERIN and OIL OF WINE.

=ETHION'IC AC'ID.= _Prep._ An alcoholic solution of the crystals of sulphate of carbyle is diluted with water, the whole neutralised with carbonate of baryta, the filtered liquid evaporated by a very gentle heat to a small bulk, and a large quantity of alcohol added; the precipitate (ethionate of baryta) is treated (cautiously) with dilute sulphuric acid (avoiding excess), by which the baryta is withdrawn, and ethionic acid left in solution.

_Prop., &c._ Ethionic acid closely resembles sulphovinic acid. It is decomposed by heat. Its salts (ethionates), however, differ completely from the sulphovinates. They are all soluble in water, and are said to be anhydrous. The ethionates of ammonia, potassa, and soda crystallise readily; those of lead, baryta, lime, and the other earths are uncrystallisable. See ISETHIONIC ACID, and _below_.

=ETHION'IC ANHY'DRIDE.= _Prep._ Pure and dry olefiant gas is passed over anhydrous sulphuric acid ('sulphuric anhydride') contained in a U-shaped tube.

_Prop., &c._ When thus produced, it is in white, milky crystals, which speedily deliquesce in the air, giving rise to ethionic acid. It is similar in appearance, and probably identical with, 'sulphate of carbyle,' which results from the absorption of the vapour of anhydrous sulphuric acid by absolute alcohol.

=E'THIOPS.= _Syn._ ÆTHIOPS, L. A name given by the older chemists to several black powders on account of their colour, and still occasionally employed in medical works.

=Ethiops, Graphi'tic.= _Syn._ ETHIOPS OF PLUMBAGO; ÆTHIOPS GRAPHITICUS, L. From plumbago, 2 parts; quicksilver, 1 part; triturated together until the globules disappear.--_Dose_, 5 to 10 gr.; in herpes, and some other obstinate skin diseases.

=Ethiops, Martial.= Black oxide of iron, prepared by keeping iron filings under water, and occasionally shaking them. It is washed with water, dried as quickly as possible, and preserved from the air, to prevent further oxidation. Formerly much esteemed as a tonic.

=Ethiops, Min'eral.= _Syn._ ETHIOPS MINERAL; ÆTHIOPS MINERALIS, HYDRARGYRI SULPHURETUM CUM SULPHURE, L. Black sulphuret of mercury, with excess of sulphur.

(Tyson's.) Oxide of mercury (prepared by decomposing calomel with an equivalent proportion of liquor of potassa to which a little liquor of ammonia has been added) and flowers of sulphur, equal parts, triturated together. This is recommended as an efficient substitute for the old and uncertain preparation commonly sold under the name of _Ethiops mineral_. It is, however, of more than double the usual strength, and should therefore be taken in proportionate doses. See MERCURY (Sulphide).

=Ethiops, Veg'etable.= _Syn._ ÆTHIOPS VEGETABILIS, PULVUS QUERCÛS MARINÆ, L. Bladder wrack (_Fucus vesiculosus_), burned in a close vessel till it becomes black and friable. Used in bronchocele, scrofula, &c. Like burnt sponge, it owes its virtues to the presence of a very minute quantity of iodine.--_Dose_, 20 gr. to 1 dr., or more, made into an electuary with honey or sugar.

=E'THYL.= C_{2}H_{5}. _Syn._ ETHYLE. The hydrocarbon assumed to be the radical of the ether-compounds (ethyl-series). A body containing carbon and hydrogen in the proportions indicated by the formula of ethyl, 2(C_{2}H_{5}), has been obtained by exposing dry iodide of ethyl in sealed tubes for several hours to the action of finely divided zinc, at a temperature of from 320° to 338° Fahr. In this reaction the iodine of the iodide of ethyl combines with the zinc, and the hydrocarbon supposed to be ethyl is set free. On opening the sealed tubes and allowing the gas (which is a mixture of the 'ethyl' and certain secondary products) to pass into a freezing mixture, the temperature of which is kept below -9° Fahr., the 'ethyl' condenses to a colourless, mobile liquid. Hitherto no compound ether has been produced from the 'ethyl' thus prepared.

According to the beautiful theory of Liebig, ethyl is a 'salt-basyle,' forming 'haloid salts' with chlorine, iodine, and bromine; its oxide is ether, and the hydrate of this oxide alcohol. The compound ethers may be compared with ordinary salts in which the metal is replaced by the radical ethyl.

=Ethyl, Oxide of.= (C_{2}H_{5})_{2}O. _Syn._ ETHER, SULPHURIC ETHER, ÆTHER (B. P.), ÆTHER SULPHURICUS (PH. E. D. & U. S.), Æ. RECTIFICATUS, Æ. VITRIOLICUS, Æ. SPIRITUS VITRIOLI DULOIS, L. A colourless, highly volatile, fragrant, inflammable liquid, obtained by distilling a mixture of sulphuric acid and alcohol. It was not known before the 13th century.

_Prep._ There are two methods employed for the preparation of ether. The one is by mixing the whole of the ingredients at once, and immediately subjecting them to distillation at a proper temperature; the other is by adding the alcohol in a slender streamlet to the acid, previously heated to the etherifying point. The former, though less economical, is the one more generally employed.

1. Rectified spirit, 3 lbs.; sulphuric acid, 2 lbs.; carbonate of potassa (previously ignited), 1 oz.; pour 2 lbs. of the spirit into a glass retort, add the acid, and place the vessel on a sand bath, so that the liquor may boil as quickly as possible, and the ether, as it forms, pass over into a well-cooled receiver; continue the distillation until a heavier fluid begins to pass over, then lower the heat, add the remainder of the spirit, and distil as before; mix the distilled liquors together, pour off the supernatant portion, add the carbonate of potassa, and agitate occasionally for one hour; finally, distil the ether from a large retort, and keep it in a well-stoppered bottle. Sp. gr. ·750.