Part 127

=Decoction of Sarsaparilla (Concentrated Compound).= _Syn._ DECOCTUM SARZÆ COMPOSITUM CONCENTRATUM, D. SARSAPARILLÆ C. C., L. There is a very considerable trade done in this article, in consequence of compound decoction of sarsaparilla being taken in large doses, both alone and in combination with other remedies, and the pharmacop[oe]ial preparation spoiling if kept longer than about 12 hours, in warm weather. Like the concentrated simple decoction, it is said to be of 8 times the usual strength, so that when mixed with 7 times its weight of water, it forms a similar preparation to the Decoctum Sarzæ Compositum,--Ph. L., for which it is very generally substituted in dispensing.

_Prep._ 1. (Wholesale.) Sarsaparilla (red Jamaica), 96 lbs.; mezereon root (not root-bark), 9 lbs.; liquorice root (bruised), 16 lbs. The mezereon and liquorice are first laid (loosely) on the bottom of a clean copper pan, and the bundles of sarsaparilla (untied and loosened) packed over them, in horizontal layers, alternately at right angles with each other. Three or four boards, with as many iron 1/2-cwt. weights, are next placed on the top of the whole. Water is now run in, to about ten inches higher than the ingredients, and heat is applied until ebullition commences. The materials are now allowed to macerate, without boiling, for 3 or 4 hours, after which the liquor is gently boiled for about an hour, care being taken to add fresh water from time to time, so as to keep the whole well covered. The decoction is next run off, and set evaporating as quickly as possible. The ingredients are then washed with successive portions of boiling water, by allowing it to descend from a species of shower-bath, after the manner of 'sparging,' described under BREWING.[256] This is repeated until the water runs off nearly colourless, the smallest quantity being employed that will effect the object in view. The whole of the liquid is now evaporated without delay, until reduced to 8-1/4 galls., when, after cooling, 2 dr. of essential oil of sassafras, dissolved in 2 galls. of rectified spirit of wine, are added, and afterwards 1 pint of essence of guaiacum. The liquid is then placed in a suitably sized barrel, set upon its head, and fitted with a small cock (not placed too near the bottom), and allowed to repose for a week, by which time it becomes clear and brilliant, and fit for sale. This is the form adopted by the large metropolitan drug-houses most celebrated for this preparation. The product that may be drawn off fit for sale is something over 10 galls. The residuum, forming the 'bottoms,' consists chiefly of fecula. The latter is well stirred up with 3 or 4 galls. of cold water, and allowed to settle. The clear decanted 'washings' are used as water or liquor in making the next batch of decoction.

[Footnote 256: See page 356.]

2. (Extemporaneous.) Compound extract of sarsaparilla, 7-1/2 oz.; boiling water, 12 fl. oz.; dissolve, then add of rectified spirit of wine, 2-1/2 fl. oz.; mix well, and further add of water, q. s. to make the whole measure a pint.

_Obs._ To conduct this process successfully, several large copper pans are required; one of which (to boil the ingredients in) must be capable of containing from 140 to 150 gallons at the least, and the others must be sufficiently large to receive the liquors as they are drawn off. Those for the evaporation should be very shallow, in order that it may proceed rapidly; and the whole should be heated by steam. An excellent plan is to employ large wooden vats, and to apply the heat by means of pipes laid along the bottom, and supplied with high-pressure steam. This method is less expensive than the use of double steam pans, as above. When essence of guaiacum is not used, 24 lbs. of guaiacum shavings, from which the dust has been sifted, are boiled with the other ingredients, instead. Those desirous of using the proportions of the ingredients ordered by the Colleges may do so by taking eight times the given quantities, and proceeding as above. The following are special preparations:--

FELTZ'S DECOCTION OF SARSAPARILLA. _Syn._ AP'OZEM OF FELTZ; DECOCTUM SARZÆ CUM ICHTHYOCOL'LA, L.; PTISANE DE FELTZ, Fr. _Prep._ From sarsaparilla (sliced), 3 oz.; isinglass and crude antimony (in powder), of each 1/2 oz.; water 5 pints; boil to one half, and strain. Used in skin diseases.

JAUPERAND'S DECOCTION OF SARSAPARILLA. _Syn._ DECOCTUM SARZÆ CUM RADICE CHINÂ, L.; PTISANE DE JAUPERAND, Fr. _Prep._ (Bories.) Sarsaparilla and China root, of each 2 oz.; senna and sassafras chips, of each 1/2 oz.; carbonate of potassa, 1 dr.; water, 2 galls.; simmer, gently, for several hours, and strain 12 pints; when cold, decant the clear.--_Dose_, 2 fl. oz., two or three times daily; in scrofula, &c.

VINACHE'S DECOCTION OF SARSAPARILLA. _Syn._ DECOCTUM SARZÆ CUM SENNÂ, L.; PTISANE DE VINACHE, Fr. _Prep._ (Foy.) Sarsaparilla, China wood, and guaiacum wood, of each 1-1/2 oz.; crude antimony (tied in a rag), 2 oz.; water, 6 pints; macerate for 12 hours (7 in hot weather), boil to one half, add sassafras chips and senna, of each 1/2 oz., infuse 1 hour longer, and strain; when cold, decant the clear. Recommended in scrofula, secondary syphilis, and various cutaneous affections.

ZITTMANN'S DECOCTION OF SARSAPARILLA. _Syn._ DECOCTUM ZITTMANNI, L.; PTISANE DE ZITTMANN, Fr. _Prep._ 1. (STRONGER DECOCTION; D. Z. FORTE, Ph. Bor. 1847.) Sarsaparilla, 12 oz.; water, 72 lbs. (say 5-3/4 galls.); digest 24 hours, then add (suspended in a bag), white sugar and alum, of each 6 dr.; calomel, 4 dr.; cinnabar, 1 dr.; boil to 24 lbs., adding towards the end of the process, senna, 3 oz.; liquorice root, 1-1/2 oz.; aniseed and fennel seed, of each 1/2 oz.; finally strain, with pressure and after some time decant the clear portion. The formula in the 'Ph. Suec.' 1845 is similar; that in the 'Hamburg Codex' directs only 24 lbs. of water to be used, and the whole to be reduced to 16 lbs.

2. (WEAKER DECOCTION; D. Z. TENUE.--Ph. Bor. 1847.) Add to the residuum (waste) of the last preparation sarsaparilla, 6 oz.; water, 72 lbs. (say, 5-3/4 galls.); boil to 24 lbs.; adding towards the end of the process, lemon peel, cinnamon bark, liquorice root, and cardamoms (all bruised), of each 3 dr.; press, strain, &c., as before. In the 'Ph. Suec.' 1845 double the above weights of lemon peel and liquorice root are ordered, and in the 'Hamburg Codex' (1845) 24 lbs. of water only are ordered, and the whole is to be boiled down to 16 lbs.

_Obs._ Both the above are used in Germany and on the Continent generally, in the same cases as those in which compound decoction of sarsaparilla is administered in England. They may be drunk almost _ad libitum_. A trace of mercury may be detected in the stronger decoction, when properly prepared. See SARSAPARILLA.

=Decoction of Sen'ega Root.= _Syn._ DECOCTION OF AMERICAN SNAKE ROOT, D. OF RATTLESNAKE ROOT; DECOCTUM POLYGALÆ, D. SENEGÆ (Ph. L.), L. _Prep._ (Ph. L.) Senega or seneka root, 10 dr.; water, 1 quart; boil to a pint, and strain.--_Dose_, 1/2 to 2 wine-glassfuls three or four times daily; in humoral asthma, chronic cough, dropsy, &c. It is stimulant, expectorant, and diuretic, and, in large doses, emetic and cathartic. It is frequently conjoined with ammonia. It is the antidote employed by the Senega Indians against the bite of the rattlesnake. (Dr Tennant.)

=Decoction of Simaru'ba Bark.= _Syn._ DECOCTUM SIMARU'BÆ, L. _Prep._ (Dr Wright.) Simaruba bark, 2 dr.; water, 24 fl. oz.; boil to one half, and strain. Tonic.--_Dose_, 1 to 2 fl. oz.; in chronic dysentery and diarrh[oe]a.

=Decoction of Squills (Compound).= _Syn._ DECOCTUM SCILLÆ COMPOSITUM, L. _Prep._ (Ph. U. S. 1841.) Squills, 3 dr.; juniper berries, 4 oz.; snake root, 3 oz.; water, 4 lbs.; boil to one half, strain, and add of sweet spirits of nitre, 4 fl. oz. In chronic coughs and other chest affections, unaccompanied with active inflammatory symptoms.--_Dose_, 1 to 3 fl. oz., twice or thrice daily.

=Decoction of Starch.= _Syn._ DECOCTUM AM'YLI (Ph. L.), MUCILA'GO AM'YLI (Ph. E. & D.), L. _Prep._ (Ph. L. & E.) Starch, 1/2 oz.; add, gradually, water, 1 pint, and boil for a short time. The Dublin preparation is nearly twice as strong. Used as an enema in dysentery, diarrh[oe]a, and excoriations of the rectum.

=Decoction, Sudorif'ic.= _Syn._ DECOCTUM SUDORIF'ICUM, L. The old name of the compound decoctions of sarsaparilla and guaiacum.

=Decoction of Su'et.= _Syn._ ARTIFICIAL GOAT'S MILK; DECOCTUM SE'VI, L. _Prep._ Suet, 1 oz.; tie it loosely in a piece of muslin and simmer it in cow's milk, 1-1/4 pint; adding towards the last, white sugar, 1/2 oz. In scrofulous emaciation and phthisis; taken _ad libitum_.

=Decoction of Tam'arinds.= _Syn._ DECOCTUM TAMARIND'ORUM, L. _Prep._ Tamarinds, 1-1/2 oz.; water, 1 pint; boil for 5 minutes, and strain. A pleasant drink in fevers, asthma, chronic coughs, &c.

=Decoction of Tamarinds and Sen'na.= _Syn._ DEC. TAMARINDORUM CUM SENNÂ (Ph. E. 1744), L. _Prep._ Tamarinds, 6 dr.; cream of tartar, 2 dr.; water, 1-1/2; pint; boil in a glazed earthen vessel until reduced to 16 oz.; then infuse therein for 12 hours, senna, 4 dr.; strain, and add of syrup of violets, 1 oz. A gentle aperient.--_Dose._ A wine-glassful, or more.

=Decoction of Tar.= _Syn._ TAR WATER; DECOCTUM PI'CIS LIQ'UIDÆ, L. _Prep._ Tar, 1 oz.; water, 1-1/2; pint; boil to 1 pint.--_Dose._ A pint or more daily; in chronic catarrh; and as a wash in chronic skin diseases, especially those of the head, in children.

=Decoction, Ton'ic.= _Syn._ STRENGTHENING DECOCTION; DECOCTUM ROBORANS, L. _Prep._ 1. Peruvian bark (bruised), 1/2 oz.; Virginian snake root, 2 dr.; water, 1 pint; boil to one half, strain whilst hot, and add, spirit of cinnamon, 1-1/2 fl. oz.; diluted sulphuric acid, 1-1/2 dr.--_Dose_, 2 oz. two or three times a day.

2. Decoction of bark, 5 oz.; tincture of bark, 6 dr.; aromatic confection, 1/2 dr.; salvolatile, 1 dr.--_Dose_, 1 or 2 table-spoonfuls night and morning; especially in diarrh[oe]a.

=Decoction of Tor'mentil.= _Syn._ DECOCTUM TORMENTIL'LÆ (Ph. L.), L. _Prep._ (Ph. L.) Tormentil root (bruised), 2 oz.; water, 1-1/2 pint; boil to a pint, and strain. Astringent.--_Dose_, 1 to 2 fl. oz., in chronic diarrh[oe]a, &c.

=Decoction of Tur'meric.= _Syn._ DECOCTUM CURCU'MÆ, L. _Prep._ From turmeric root (in powder), 1-1/2 oz.; water, 1 pint; boil for 5 minutes, and strain. A mild aromatic stimulant and stomachic.--_Dose._ A wine-glassful _ad libitum_. It is principally used as a test for alkalies, which turn it brown. Unsized paper dipped into it and dried forms the turmeric test-paper of the chemist.

=Decoction of Verbe'na.= _Syn._ DECOCTUM VERBE'NÆ, L. From verbena (vervain), 2 oz.; water, 1-1/2 pint; boil to 1 pint, and strain.

_Obs._ The _Verbena officinalis_ was formerly highly recommended by Etmuller, Hartman, De Haën, Morley, and others, in scrofula, cephalalgia, &c., but afterwards fell into neglect. More recently, a decoction of the plant has been highly extolled by Boshanov and others as an anti-febrile.

=Decoction, Vul'nerary.= _Syn._ DECOCTUM VULNERA''RIUM, L. _Prep._ From ground ivy and broad-leaved plantain, of each 1/2 oz.; water, 3 pints; boil to 1 quart, strain, and add sugar, 1 oz. A popular pectoral and tonic, especially in old coughs; also to heal wounds.--_Dose_, 1/2 a teacupful or more twice a day.

=Decoction of Wal'nut Bark.= _Syn._ DECOCTUM JUGLAND'IS, L. _Prep._ (Ph. Gen.) Green bark of walnuts, 1 oz.; water, 1 pint; boil for 15 minutes, and strain. As an anti-syphilitic. Before the general introduction of sarsaparilla it was much esteemed in most cases in which that drug is now taken.--_Dose, &c._ The same as those of comp. dec. of sarsaparilla. Pearson says that "when the putamen (green rind) of the walnut has been omitted, either intentionally or by accident (from _Decoctum Lusitanicum_), the same good effects have not followed its use as when it contained this ingredient.

=Decoction of Walnut Leaves.= _Syn._ DECOCTUM JUGLAND'IS FOLIO''RUM, L. _Prep._ (Negrier.) Walnut leaves, 1 handful; water, 1 quart; boil 15 minutes, and strain. Detersive, diaphoretic, and alterative.--_Dose, &c._ As the last, especially in chronic rheumatism, secondary syphilis, &c.

=Decoction of Wa'terdock.= _Syn._ DECOCTUM RUMI'CIS, D. R. AQUAT'ICI, L. _Prep._ (A. T. Thomson.) Root of common waterdock (_Rumex obtusifolius_), 1 oz.; water, 1 pint; boil for 10 minutes, and strain.

_Obs._ This decoction is astringent, and was once much celebrated as a remedy for scurvy and some other cutaneous affections. "It is the only remedy which proves efficacious in that disease when the ulcers are healed, and the patient is attacked with asthma." (Linnaeus, on the Scurvy of the Laplanders.)

=Decoction, White= (Sydenham's). _Syn._ HARTSHORN DRINK; MIS'TURA COR'NU USTI. _Prep._ Prepared burnt hartshorn, 2 oz.; gum Arabic, 1 oz.; water, 3 pints; boil to 1 quart, and strain. Mucilaginous; demulcent. Taken _ad libitum_.

=Decoction of Whor'tleberry.= _Syn._ DECOCTION OF BEAR-BERRY, D. OF UVA-URSI; DECOCTUM UVÆ URSI (Ph. L. & D.), L. _Prep._ 1. (Ph. L.) Whortleberry leaves, 1 oz.; water, 1-1/2 pint; boil to a pint, and strain.

2. (Ph. D.) Uva-ursi (the leaves), 1/2 oz.; water, 1/2 pint; boil 10 minutes, and strain.

_Dose, &c._ 1 to 3 fl. oz. two or three times daily; in phthisis and purulent affections of the urinary organs, unaccompanied with active inflammation; especially in chronic affections of the bladder.

=Decoction of Wil'low Bark.= _Syn._ DECOCTUM SALICIS, D. S. CORTICIS, L. _Prep._ 1. (Wilkinson.) Willow bark (_Salix latifolia_), bruised, 1-1/2 oz.; macerate in water, 2 lbs., for 6 hours, then boil for 15 minutes, and strain. Tonic, astringent, and febrifuge.--_Dose._ A wine-glassful.

2. (Nieman.) Willow bark (_Salix alba_), 1-1/2 oz.; water, 3/4 pint; boil to one half.--_Dose_, 1 to 2 fl. oz. Both are used as substitutes for decoction of cinchona bark.

=Decoction of Win'ter-green.= _Syn._ DECOCTION OF PYROLA, D. OF UMBELLATED WINTER-GREEN, D. OF PIPSISSEWA; DECOCTUM CHIMAPHILÆ (Ph. L.), D. PYROLÆ (Ph. D.), L. _Prep._ 1. (Ph. L.) Chimaphila (dried herb), 1 oz.; water, 1-1/2 pint; boil to a pint, and strain.

2. (Ph. D.) Winter-green (dried leaves), 1/2 oz.; water, 1/2 pint; boil 10 minutes in a covered vessel, and strain. Tonic, stomachic, alterative, and diuretic.--_Dose_, 1 to 2 fl. oz.; in dropsies, scrofula, debility, loss of appetite, &c.; and in those affections of the urinary organs in which uva-ursi is commonly given.

=Decoction of Worm'seed.= _Syn._ DECOCTUM SANTONICI, L. _Prep._ 1. Wormseed, bruised, 2 oz.; water, 1 pint; boil down to 16 fl. oz., and strain.

2. (Dr R. E. Griffith.) Fresh leaves of wormseed(_Chenopodium anthelminticum_),--Linn.), 1 oz.; water, 1 pint; orange peel, 2 dr.; boil (10 minutes), and strain. The above are bitter, stomachic, and vermifuge.--_Dose._ A wine-glassful twice a day; in worms. It is also used as an injection against ascarides.

=Decoction of Yar'row.= _Syn._ DECOCTUM MILLEFOLII, L. _Prep._ From milfoil or yarrow tops, 1-1/2 oz.; water, 1-1/4 pint; boil to a pint, and strain. Astringent, tonic, and vulnerary.--_Dose._ A wine-glassful thrice daily; in dropsies, &c. It is also used as a fomentation to bruises, &c.

=Decoction of Black Snake Root.= _Syn._ DECOCTUM CIMICIFUGE. Black snake root, 1 oz.; water, 16 oz.; boil for 10 minutes.--_Dose_, 1 oz. to 2 oz. in rheumatism and dropsy.

=Decoction of Stavesacre.= _Syn._ DECOCTUM STAPHISAGRIÆ. Stavesacre seed, 1 oz.; water, 2 pints; boil for a few minutes, and strain. For external use.

=Decoction of Snails.= _Syn._ DECOCTUM LIMATUM (MARS MOUCHON). Flesh of vine or garden snails (cleansed from shell and intestines), 5 oz.; water, 2 pints; simmer gently for 2 hours, adding towards the end, maiden hair 2 oz., and strain.

=Decoction of Soapwort.= _Syn._ DECOCTUM SAPONARIÆ (SWEDIAUR). Soapwort, 2 oz.; water, 4 lbs.; boil to 2 lbs., and strain.

=Decoction of Wood-Soot.= _Syn._ DECOCTUM FULIGINIS (Dr Neligan). Wood-soot, 4 oz.; water, 1-1/2 pint.

=DECOLORA'TION.= The blanching or removal of the natural colour of any substance. Syrups and many animal, vegetable, and saline solutions are decoloured or whitened by agitation with animal charcoal, and subsequent subsidence or filtration. Many fluids rapidly lose their natural colour by exposure to light, especially to the direct rays of the sun. In this way castor, nut, poppy, and several other oils are whitened. Fish oils are partially deodorised and decoloured by filtration through animal charcoal. Cottons and linens are still commonly bleached by the joint action of light, air, and moisture. The peculiar way in which light produces this effect has never been satisfactorily explained. The decoloration of textile fabrics and solid bodies generally is called bleaching. See BLANCHING, BLEACHING, OILS, TALLOW, SYRUPS, SUGAR, &c.

=DECOMPOSI''TION= (-z[)i]sh'un). In _chemistry_, the resolution of compounds into their elements, or the alteration of their chemical constitution in such a manner that new products are formed.

=DEFECA'TION.= The separation of a liquid from its lees, dregs, or impurities by subsidence and decantation. It is commonly employed for the purification of saline solutions and glutinous or unctuous liquids on the large scale in preference to filtration; than which it is both more expeditious and expensive. See CLARIFICATION, DECANTATION, FILTRATION, &c.

=DEFLAGRA'TION.= The sudden combustion of any substance for the purpose of producing some change in its composition, by the joint action of heat and oxygen. The process is commonly performed by projecting into a red-hot crucible, in small portions at a time, a mixture of nitrate of potash, and the body to be oxidised.

=DELIQUES'CENCE.= Spontaneous liquefaction by absorption of the moisture of the atmosphere. Deliquescent salts are those which by exposure gradually assume the liquid state. They should all be kept in well-closed bottles or jars.

=DELIR'IUM TRE'MENS.= [L.] The madness of drunkards; a disease of the brain resulting from the excessive and protracted use of intoxicating liquors, particularly of ardent spirits. The early symptoms are extreme irritability and fretfulness, with unusual mobility of the body. Sleeplessness and unpleasant dreams soon follow. At length frightful dreams and visions harass the patient. He sees remarkable sights, hears extraordinary sounds, and labours under all the strange delusions of insane persons, which, however vague and unfounded, operate on him with all the force of realities till he becomes furiously mad. The fit almost always comes on after hard drinking; and the hands are usually, but not always, tremulous. A similar affection is occasionally produced by the abuse of opium, excessive mental anxiety, night watching, or depletion. According to Dr Armstrong, even respiring the fumes of ardent spirits will, under some circumstances, produce this disease. Persons who have undergone surgical operations under the influence of chloroform are more liable to attacks of this kind than other persons.

The _treatment_ of delirium tremens consists mainly in the judicious use of opium, laudanum, or morphia, in rather large doses, frequently repeated. Thirty to sixty drops of laudanum may be given every hour or two during the fit, its effects being carefully watched. The object is to produce quiet sleep, from which the patient usually wakes free from the worst symptoms of the disease. Diaphoretics and mild aperients may also be given, and a light, nutritious diet adopted throughout. Depletion, especially bleeding, should be particularly avoided. Alcoholic stimulants and wine, in certain cases, have proved useful. Under this treatment, the patient, unless of a very bad habit of body, or much debilitated by previous excesses, usually recovers. He is, however, very liable to relapses and subsequent attacks, which are best prevented by judicious moral management.

The judicious administration of chloral hydrate, in doses of from thirty to sixty grains as well as of bromide of potassium in twenty-grain doses, either alone or combined with the chloral, has lately been had recourse to with the happiest results, for the production of sleep in cases of delirium tremens or in the insomnia of dipsomaniacs.

The repetition of the dose of chloral requires to be regulated with very great caution; and it is only in the case of emigrants and others unable to obtain medical aid that we would recommend it to be given, and then only should opium have failed to produce the desired effect. Not _more_ than sixty grains of the chloral should be administered during the twenty-four hours. The internal administration of tincture of capsicum in moderately large doses, in the intervals of the opiates or chloral hydrate, has lately been tried in the treatment of this disease, it is said, with success.

=DELPHIN'IC ACID.= _Syn._ PHOCE'NIC ACID. A fatty acid, obtained by saponifying the oil of the delphinus or porpoise. According to recent experiments, it is identical with valeric acid.

=DELPHIN'INE.= _Syn._ DEL'PHINE, DEL'PHIA, DELPHIN'IA. An alkaloid discovered by Lassaigne and Feneulle in _Delphinium staphysagria_ or stavesacre.

_Prep._ 1. The husked seeds (in powder) are boiled in a little water, and pressed in a cloth; a little pure magnesia is then added to the filtered decoction, the whole is boiled for a few minutes, and refiltered; the residuum, after being well washed, is digested in boiling alcohol, which dissolves out the alkaloid, and gives it up again by gentle evaporation and cooling.

2. The bruised, but unshelled, seeds are digested in dilute sulphuric acid, the filtered liquor precipitated with carbonate of potassa, and the precipitate digested in alcohol as before.

3. (Parrish.) An alcoholic extract of the seeds is treated with dilute sulphuric acid, precipitated with an alkali, again dissolved in dilute sulphuric acid; the colouring matter precipitated by a few drops of nitric acid, the alkaloid by potassa. The alkaloid is then dissolved in absolute alcohol, and the solution thus formed is evaporated; one pound yields about one drachm.

_Prop., &c._ A light-yellowish or white, odourless powder; extremely acrid and bitter; scarcely soluble in water; dissolves in ether, and readily in alcohol; and has an alkaline reaction. Its alcoholic solution produces a burning and tingling sensation when rubbed on the skin, and a similar sensation is produced in various parts of the body when it is taken in doses of a few grains. It has been exhibited in neuralgia and rheumatism by Dr Turnbull.--_Dose_, 1/12 gr. every three hours, made into a pill with 1 gr. each of the extracts of henbane and liquorice. It is also used externally under the form of ointment and lotion.

=DELPHINUM--A Boot Varnish.= Shell-lac, 7·5 grammes dissolved in alcohol, 15 grammes, mixed with 20 drops fish oil, and ·1 gramme lampblack. (Geisse.)

=DEMUL'CENTS.= In _medicine_, substances which are calculated to soften and lubricate the parts to which they are applied. Though having the same signification as the word EMOLLIENTS, it is desirable to restrict the latter term to such as are intended for external application, and to include under the above head only such as are intended for internal exhibition. The principal demulcents are gum Arabic, gum tragacanth, liquorice, honey, arrow-root, pearl barley, isinglass, gelatin, milk, almonds, spermaceti, almond and olive oils, and most other mucilaginous, amylaceous, saccharine, and oily substances. For use, these are made into MUCILAGES, DECOCTIONS, EMULSIONS, or MILKS, with water, and form suitable beverages in dysentery, diarrh[oe]a, catarrh, diseases of the urinary organs, and all other diseases where diluents are useful. See EMOLLIENTS.