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 1·25%.
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; Terebinthinæ oleum (B. P.), Spiritus terebinthinæ, Essentia t., Oleum terebinthinæ (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 TEREBINTHINÆ 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 71⁄2 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.