TURPENTINE is a semi-solid resin which is yielded by various species of pine, and by some other trees when incisions are made into them. The chief varieties of turpen tine are common turpentine, yielded by pines abies; Venice turpentine, yielded by the larch; Bordeaux turpentine, yielded by pines maritima; and Chian turpentine, yielded by pistacia lentiscus. The Venice turpentine, which is regarded as the best variety, occurs as a clear, transparent, pale yellow, viscous mass, of a balsamic odor, and an acrid bitter taste, perfectly soluble in spirits of wine, and increasing in density ou prolonged expo sure to the air. On distilling•it with water it yields a considerable quantity of essential oil, vulgarly known as spirits of turpentine. This oil of turpentine (which, from its greater cheapness, is usually obtained from common turpentine) is, after rectification, represented by the formula and has a spec. gray, of 0.864, and a boiling-point of 390°. It is colorless, transparent, has a strong refractive power, a strong peculiar odor, and a disagreeable acrid taste. It is readily soluble in alcohol, in ether, and in the fixed and essential oils, but is insoluble in water, on which it floats. It is a good solvent for many substances, among which may be especially mentioned sulphur, phosphorus, caoutchouc, and the various resins; and is largely used in many depart ments of the arts, forming a large proportion of all oil paints. Great quantities are imported into Britain from the United States, where it is Mostly yielded by the swamp pine.
Turpentine is an energetic producer of ozone (q.v.); and on keeping it for a long time in a stoppered flask, which should be occasionally shaken, the odor of ozone is very distinct on opening the vessel. Oil of turpentine forms three hydrates, of which two are solid. Commercial oil of turpentine often consists of a mixture of several isomeric hydrocarbons which act oppositely on polarized light (like the several varieties of sugar). Deville and Berthelot have ascertained that there are various modifications of which this oil is susceptible without its undergoing any change in its chemical composition. Of these, isoterebenthene .and metatercbenthene differ inter alia in their boiling-points, and may thus be separated; terebene (which has an odor resembling that of oil of cloves) and colophene are obtained by acting on the oil with sulphuric acid; and camphilene and tere bilene by decomposing artificial camphor (which is a combination of the oil with hydro chloric acid) by means of quicklime.
Under the influence of nitric, hydrochloric, and sulphuric acids, chlorine, etc., oil of turpentine yields many products of interest to the chemist, but as yet of little prac tical value.
Oil of turpentine is used to a considerable extent in medicine, although, from its disagreeable taste, and from certain bad effects which occasionally follow its use (as strangury, bloody urine, vertigo, a species of intoxication, and an eruption on the skin), it is often supplanted by less certain remedies. It is probably the most effective remedy
for the expulsion of tapeworm, is nearly equally efficacious over the lumbrici or round worms, and in the form of an injection is serviceable in the case of ascarides or thread worms. For an adult, in the case of tapeworm or round worm, the dose should be one ounce, combined with an equal quantity of castor-oil, or made into an emulsion with yoke of egg or mucilage. In the case of children and delicate women, it is better to try a milder vermicide (see VERMIFUGES). In doses of from two drams to two ounces, and in similar combination with castor-oil, it. may be given as a cathartic in cases of obsti nate constipation, especially when dependent on affections of the brain; in hysteria, epilepsy, tympanitis. passive hemorrhage, and in purpura heinorrhagica, in which list named disease Dr. Neligan highly recommends it. in small doses (as from 10 to 20 minims), oil of turpentine is regarded ns a diuretic; but it must be given with (tuition, in consequence of its stimulating properties. It is of more service in chronic mucous discharges of the genitourinary organs, as gleet, leueorrlima, etc., than in dropsy. In small doses, it is often useful in chronic rheumatism and in sciatica. In the Dublin school, it is much employed in small and repeated doses as a general stimulant in the low stages of continued fever. Turpentine punch has long been a lavorite remedy in the Meath hospital (where Graves and Stokes made their reputation) in these cases. It is composed of an ounce of oil of turpentine, two ounces of brandy, eight ounces of boiling water, and a sufficient quantity of sugar. A third of this should be taken for a dose, and should be repeated if necessary every third hour. When applied externally, oil of turpentine is a speedy and powerful rubifacient and counter-irritant, and is bene ficially used in this capacity in inflammatory attacks of the throat, chest, and abdomen. The best method to pursue is to rub the oil by means of a bit of flannel over the part to be acted on; over this to lay three or four folds of flannel, wrung out of hot water, and over the flannel to place a dry towel; two or three such applications produce it sufficient result. There is a liniment of turpentine which is powerfully stimulating, and is applied as a dressing for extensive burns; and is likewise used, with friction, in rheumatic and neuralgic cases. There is also the liniment of turpentine and acetic acid, whi,1 is the officinal representative of the well-known St. John Long's liniment, and is an excellent counter-irritant (applied with a sponge) in pulmonary consumption and other chronic pulmonary affections. Lastly, ointment of turpentine, a warm stimulating application, requires mention.
It was mentioned at the beginning of this article that on distilling turpentine with water, the oil comes over. The residue left in the retort constitutes common Te8111, (or rosin), known also as colophony. See RESINS.