=Oil of Sweet Flag.= _Syn._ OLEUM ACORI, O. A. AROMATICA, L. From the rhizomes or roots of _Acorus calamus_ (Linn.), or sweet flag. Yellow; agreeably fragrant. Used to scent snuff, aromatic vinegar, &c. _Prod._ Fresh rhizomes, 3/4 to 1%; dried (recent), 1 to 125%.
=Oil of Tan'sy.= _Syn._ OLEUM TANACETI, L. From the flowering herb of _Tanacetum vulgare_ (Linn.), or tansy. Pale greenish yellow; very odorous; bitter; aromatic. Sp. gr. 946 to 950. _Prod._ Fresh, 25% to 5%; dried (recent), 3/4 to 1%(fully).
=Oil of Thyme.= _Syn._ OLEUM THYMI; OIL OF ORIGANUM; OLEUM ORIGANI (of the shops). From the flowering herb of _Thymus vulgaris_ (Linn.), or garden thyme. Nearly colourless; the imparted oil has a reddish colour, which it loses by rectification; very fragrant; acrid; hot tasted, stimulant, and rubefacient; boils at 354 Fahr. Sp. gr. 867 to 875. _Prod._ 5% to 75%.
_Obs._ This is the dark-coloured 'OIL OF ORIGANUM' of the shops. It is frequently adulterated with oil of turpentine. It is occasionally used in toothache and in stimulating liniments; but its chief consumption is in perfumery, more particularly for hair oils, pomatums, and hair-washes, as it is reputed to make the hair grow and to prevent baldness.
=Oil of Tobac'co (Volatile).= From the leaves of _Nicotiana tabacum_ (Linn.), or the tobacco plant. Concrete.
=Oil of Turpentine.= _Syn._ SPIRIT OF T., ESSENCE OF T., TURPS, CAMPHENE, CAMPHINE; TEREBINTHINae OLEUM (B. P.), SPIRITUS TEREBINTHINae, ESSENTIA T., OLEUM TEREBINTHINae (Ph. L. & D.), O. T. PURIFICATUM (Ph. E.), L. The oil of turpentine of commerce is obtained by distilling strained American turpentine along with water. The residuum in the still is 'resin' or 'rosin.' The product in oil varies from 14% to 16%. The colleges order it to be rectified before being employed for medicinal purposes. This is effected by redistilling it along with 3 or 4 times its volume of water, observing not to draw over quite the whole. The portion remaining in the retort (balsam of turpentine) is viscid and resinous. A better plan is to well agitate it with an equal measure of solution of potassa or milk of lime before rectifying it. This is the plan adopted for the camphine used for lamps. By agitating crude oil of turpentine with about 5% of sulphuric acid, diluted with twice its weight of water, and after repose and decantation rectifying it from 5 or 6 times its volume of the strongest lime water, a very pure and nearly scentless oil may be obtained. Dr Nimmo recommends oil of turpentine to be purified by agitation with 1/8th part of rectified spirit, after repose to decant the spirit, and to repeat the process 3 or 4 times. The product retains, however, fully 1/5th part of spirit in solution, and hence this method is objectionable, except for medicinal purposes, for which, according to Dr Garrod, it is better than the oil purified by rectification. The sweet spirits of turpentine (SPIRITUS TEREBINTHINae DULCIS), vended of late years in the shops, is simply the common oil which has been agitated with, and rectified from, somewhat dilute sulphuric acid.
_Prop._ Pure oil of turpentine is colourless; limpid; very mobile; neutral to test-paper; has an odour neither powerful nor disagreeable when recently prepared, but becoming so by exposure to the air; dissolves 1/5th part of alcohol of 830; is soluble in 6 parts of ether and in 7-1/2 parts of rectified spirit; hot strong alcohol dissolves it freely, but the greater part separates in globules as the liquid cools. Oil of vitriol chars it, and strong nitric acid attacks it violently, even with flame. It congeals at 14, and boils at 312 Fahr. Sp. gr. 867; that of the oil of the shops varies from 872 to 878. It possesses a very high refractive power. At 72 it absorbs 163 times its volume of hydrochloric-acid gas (if kept cool), and in 24 hours from 26% to 47% of crystals (KIND'S CAMPHOR) separate. These have a camphoraceous odour, and, after being washed with water, and sublimed along with some dry chalk, lime, or charcoal, assume the form of a white, translucent, flexible, crystalline mass, which is volatile, soluble in alcohol, and possesses a considerable resemblance to camphor. A nearly similar substance is produced by the action of oxygen gas on oil of turpentine.
_Uses, &c._ Oil of turpentine is extensively used in the manufacture of varnishes and paints. Under the name of 'camphine' it is occasionally employed for burning in lamps. For the last purpose it must be newly rectified and preserved from the air. By exposure it rapidly absorbs oxygen, resin is formed, its density increases, and it gives a dull fuliginous flame. In medicine it is employed as a diaphoretic, stimulant, vermifuge, &c.--_Dose_, 6 to 30 or 40 drops; in rheumatism, hemicrania, &c., 1 fl. dr. every four hours, in combination with bark or capsicum; in tapeworm, 3 fl. dr. to 1 fl. oz., either alone or combined with a little syrup of orange peel, every 8 hours, until the worm is expelled. The common symptoms of large doses of this oil are dizziness and a species of temporary intoxication, and occasionally nausea and sickness, which subside after two or three alvine evacuations, leaving no other effect, when the oil is pure, than a certain degree of languor for a few hours. In tapeworm a little castor-oil may be advantageously combined with the second and subsequent doses. Oil of turpentine imparts a violent odour to the urine. To prevent loss by evaporation and resinification, this oil should be kept in tin cans or glass bottles. For store vessels, closely covered tin cisterns are the best. To _prevent accidents_ it is proper to caution the operator of the extremely penetrating and inflammable nature of the vapour of this oil, even in the cold. During the process of its distillation, without the greatest precautions are taken, an explosion is almost inevitable.
=Oil of Vale"rian.= _Syn._ OLEUM VALERIANae (Ph. Bor.), L. From the root of _Valeriana officinalis_ (Linn.), or wild valerian. Yellowish; viscid; lighter than water; smells strongly of the plant. By exposure to the air it is partly converted into valerianic acid, and more readily so under the influence of an alkali. In its usual form it consists of valerol, a neutral oily body; borneene, a volatile liquid hydrocarbon; and valerianic acid. It is powerfully antispasmodic, emmenagogue, tonic, and stimulant, and, in large doses, narcotic.--_Dose_, 2 to 6 drops; in epilepsy, hysteria, hemicrania, hypochondriasis, low fevers, &c. _Prod._ 1-1/4% to 2% (nearly).
=Oil of Ver'bena.= _Syn_. OLEUM VERBENae, L. From the fresh flowering herb of _Verbena odorata_. _Prod._ 2% to 5%. The 'OIL OF VERBENA' of the shops is imported from India, and is obtained from _Andropogon citratum_. See OIL OF LEMON GRASS.
=Oil of Wine.= SYN. HEAVY OIL OF WINE, ETHEREAL OIL, OILY ETHEREAL LIQUOR, SULPHATE OF ETHER AND ETHEROLE; OLEUM aeTHEREUM (Ph. L.), OLEUM VINI, LIQUOR aeTHEREUS OLEOSUS, L. This is an artificial production which, for convenience, may be included under this head.
1. (Ph. L.) Rectified spirit, 2 pints, and sulphuric acid, 36 fl. oz., are cautiously mixed together in a glass retort, and submitted to distillation until a black froth appears, when the retort is immediately removed from the fire (sand heat); the lighter, supernatant, liquor is next separated from the fluid in the receiver, and exposed to the air for 24 hours; it is then agitated with a mixture of solution of potassa and water, of each 1 fl. oz., or q. s., and, when, sufficiently washed, is, lastly, separated from the aqueous liquid from which it has subsided. The formula of the Ph.
L. 1836 is nearly similar.
2. (Ph. D.) Rectified spirit and oil of vitriol (commercial), of each 1-1/2 pint; as the last, employing a Liebig's condenser, and a capsule for the exposure to the air; the oil is then transferred to a moistened paper filter, and washed with a little cold water, to remove any adhering acid.
3. (Ph. D. 1826.) From the residuum in the retort after the process of preparing ether, distilled to one half, by a moderate heat, and the oil treated as before.
4. From rectified spirit (sp. gr. 833), 2 parts; oil of vitriol, 5 parts; mix and distil, as before; wash the product with distilled water, and free it from adhering water and undecomposed alcohol by exposure in the vacuum of an air-pump, between two open capsules, the one containing fragments of solid potassa, and the other concentrated sulphuric acid. Pure.
5. By distilling a mixture of ether and oil of vitriol, and treating the product as before.
6. By the destructive distillation of dry sulphovinate of calcium; the product is freed from alcohol, &c., by washing it. This process yields the largest product.
_Prop., &c._ An oily liquid, nearly colourless, neutral, with an aromatic taste, and an odour resembling that of oil of peppermint. It is insoluble in water, but freely soluble in both alcohol and ether; boiling water converts it into sulphovinic acid, and a volatile liquid called light or sweet oil of wine; with an alkaline solution, this effect is produced with even greater facility. Sp. gr. 105 (Hennel & Ph. L.); 113 (Serullas).
Boils at 540 Fahr. "Dropped into water, it sinks, the form of the globule being preserved." (Ph. L.) _Prod._ 125 to 15%; 33 lbs. of rectified spirit, and 64 lbs. of oil of vitriol, yield 17 oz. of this oil (Hennel).
_Uses._ Oil of wine is reputed anodyne, but is only used in the preparation of other compounds. See SPIRIT OF ETHER (Compound), &c.
=Oil of Wine (Light).= _Syn._ SWEET OIL OF WINE. See ETHERIN, ETHEROLE, and _above_.
=Oil, Wood (of India).= From the _Chloroxylon Swietenia_ (De Cand.), the tree which yields the satin-wood of the cabinet-makers. Another wood oil (GURJUN BALSAM) is obtained by incision from various species of _Dipterocarpus_. This balsam yields about 38% of a volatile oil by distillation, which in its general properties closely resembles OIL OF COPAIBA. (O'Shaughnessey.)
=Oil of Worm'seed.= _Syn._ OLEUM CHENOPODII (Ph. U. S.), L. From the seeds of _Chenopodium anthelminticum_, or Jerusalem oak (American wormseed).
Light yellow, or greenish; powerfully anthelmintic. Sp. gr. 908.--_Dose._ For an adult, 25 to 30 drops, in sugar, honey, or milk, night and morning, for 3 or 4 days, followed by a good dose of castor oil, or some other suitable purgative.
=Oil of Worm'wood.= _Syn._ OLEUM ABSINTHII, L. From the herbaceous portion of _Artemisia absinthium_, or common wormwood; green or brownish-green; odorous; acrid; bitter; stomachic. Sp. gr. 9703 (Brisson); 9720 (Pereira); 9725 (Brande). _Prod._ Fresh herb (picked), 1/4 to 1/3%, dry herb (a year old), 1/2% (fully); do. (recent), 3/4 to 1% (fully).
_Pur._ That of the shops is nearly always either adulterated or partly spoiled by age; hence the discrepancies in the densities given for this oil by different authorities. A specimen of this oil distilled by Mr Cooley from the green plant had the sp. gr. 9712; but after being kept for 12 months, it had increased to 9718. Nitric acid of 125 colours the pure oil first green, then blue, and, lastly, brown. The positive character of these reactions is in direct proportion to the purity and freshness of the sample.
=OILY EMUL'SION.= See LINCTUS (Emollient).
=OILY ETHE"REAL LIQ'UOR.= See OIL OF WINE (_above_).
=OINT'MENT.= _Syn._ UNGUENTUM, L. Any soft, fatty substance applied to the skin by inunction. The term is now commonly restricted to those which are employed in medicine.
Ointments (unguenta) differ from 'cerates' chiefly in their consistence, and in wax not being a constant or essential constituent; and they are made and used in a nearly similar manner to that class of preparations.
Their proper degree of solidity is that of good butter, at the ordinary temperature of the atmosphere. When the active ingredients are pulverulent substances, nothing can be more suitable to form the body of the ointment than good fresh lard, free from salt; but when they are fluid or semi-fluid, prepared suet, or a mixture of suet and lard, will be necessary to give a due consistence to the compound. In some instances wax is ordered for this purpose. Another excellent 'vehicle' for the more active ingredients is a simple ointment, formed by melting together 1 part of pure white wax with about 4 parts of olive oil. The use of the last excludes the possibility of the irritation sometimes occasioned by the accession of rancidity, when inferior lard is employed. In a few cases butter is employed to form the body of the ointment.
Some ointments are made from recent vegetable substances by infusion or coction, in the manner adopted for medicated oils. See OILS, MEDICATED.
The precautions to be used in the choice of lard are noticed in the article devoted to this substance. Lard is included in the Materia Medica of the London College. In the last Ph. D. lard for medicinal use (ADEPS SUILLUS PRaePARATUS--Ph. D.) is ordered to be prepared by melting it in twice its weight of boiling water, stirring it constantly for some time, then setting the mixture aside to cool; and, lastly, separating the fat when it has solidified.
Ointments are best preserved by keeping them in salt-glazed earthen or stoneware jars, covered with tin foil, in a cool situation.
The accession of rancidity in ointments and other unctuous preparations may be greatly retarded, if not wholly prevented, by previously dissolving in the fat about 2% of gum-benzoin, in fine powder, or rather less quantity of benzoic acid by the aid of heat. This addition renders the ointment peculiarly soothing to irritable or highly sensitive skins.
Poplar buds act in a similar manner.
? The formulae for all the more useful and generally employed ointments are given below. Those not included in the list may be prepared of the proper strength for all ordinary purposes, by combining about 12 to 15 times the medium dose of the particular medicinal with 1 oz. of lard or simple ointment. For substances which possess little activity, 1/2 to 1 dr. per oz., or even more, may be taken. See CERATE, FAT, &c.
=Ointment of Ac'etate of Lead.= _Syn._ UNGUENTUM PLUMBI ACETATIS (B. P., Ph. E. & D.), L. _Prep._ 1. (Ph. E.) Acetate of lead, in fine powder, 1 oz.; simple ointment, 20 oz.; mix them thoroughly (by trituration).
2. (Ph. D.) Ointment of white wax, 1 lb.; melt by a gentle heat, then add, gradually, of acetate of lead, in very fine powder, 1 oz., and stir the mixture until it concretes.
3. (B. P.) Acetate of lead, in fine powder, 12 gr.; benzoated lard, 1 oz.; mix.
_Obs._ A useful, cooling, astringent, and desiccative ointment. For the formula of Ph. L., see CERATE.
=Ointment, Ace'tic.= See OINTMENT, VINEGAR.
=Ointment of Ac'onite.= _Syn._ UNGUENTUM ACONITI, L. _Prep._ 1. (Dr Turnbull.) Alcoholic extract of aconite, 1 part; lard, 2 parts; carefully triturated together. In neuralgia, &c.
2. (Ammoniated; UNGUENTUM ACONITI AMMONIATUM--Turnbull.) Ammoniated extract of aconite, 1 part; lard, 3 parts. In neuralgia, paralysis, old rheumatic affections, &c. The use of the above preparations of aconite requires the greatest caution. They are intended as substitutes for OINTMENT OF ACONITINE, a still more dangerous preparation.
=Ointment of Acon'itine.= _Syn._ UNGUENTUM ACONITINae, L. _Prep._ 1. (Dr Garrod.) Pure aconitine, 1 gr.; lard, 1 dr.; mix by careful trituration.
2. (Dr Turnbull.) Aconitine, 2 gr.; rectified spirit, 6 or 7 drops; triturate together, then add of lard, 1 dr., and mix well.
3. (B. P.) Aconitia (aconitine), 8 gr.; rectified spirit, 1/2 dr.; dissolve and add lard, 1 oz.; mix.
_Use, &c._ As a topical benumber in neuralgic affections, rheumatic pains, &c. Its application generally occasions considerable tingling, and sometimes redness of the part to which it is applied, followed by temporary loss of sensation in the skin and the cessation of the pain. For slight cases Dr Paris formerly employed only 1 gr. to the oz. Owing to the intensely poisonous nature of aconitine, this ointment must be both prepared and used with great caution, and must never be applied to an abraded surface. It is seldom employed, owing to its extreme costliness.
See ACONITIA, and _above_.
=Ointment, Ague.= See OINTMENT, ANTIPERIODIC.
=Ointment, Albinolo's.= See PATENT MEDICINES.
=Ointment, Alkaline.= _Syn._ UNGUENTUM ALKALINUM, L. _Prep._ 1. (Biett.) Carbonate of soda, 2 dr.; fresh-slaked lime, 1 dr.; powdered opium, 2 gr.; lard, 2 oz.; mix by trituration. In prurigo, ringworm, and some other cutaneous affections.