When oil of turpentine Is agitated with five per cent, of strong sul phuric acid, it becomes of a dark red colour, and viscid. On standing, the man separates into two portions, and the upper clear liquid fur nishes, on distillation. a body having the same boiling-point and corn position as the original oil, but of an odour resembling that of oil of thyme : it Is called tereben. Colophen is produced at the same time as tereben ; Its density, however, Is twice as great, and Its boiling-point is between 500' and 600* Fehr. It may also beobtained from colophony, hence Its name. Neither tereben nor colophon has any action upon polarised light.
Water combines with oil of turpentine to form definite hydrates, of which three are solid and one liquid. When the oil is exposed to intense cold, crystals of Linhydrate (C,„Ii,„. 2110) sotnetimes separate, but generally a her:Ow/role 6110), called teepie, In large prismatic crystals, is deposited. The latter may be in quan tity by well mixing four parts of oil of turpentine, one of nitric held (tap. gr. 1.36), and three of alcohol (ep. gr, 0.840), and setting aside for several weeks. When sublimed, the hexahydrato Jones two equivalents of water, and Is converted into a quadllydrote 4110). The quadhydrate is also formed on exposing turpentine and water to a con tinuod heat of about 120' Fehr. It Is more soluble in hot than cold water, and Is readily taken up by alcohol, ether, or benzoic. A fourth hydrate, termed terpinol (C,11,,„110), which a at common tem peratures, is formed on distilling either of the other hydrates with water containing a little hydrochloric or sulphuric acid. It has an odour like that of the hyacinth, boils at 334° Fehr., and is of ep. gr. 0.852.
Hydrochloric acid combines with oil of turpentine, and forms several liquid and solid bodies. The latter have very much the appearance and odour of camphor, and hence are termed artificial camplunw. The monohydrochlorate HCl), called also hydrochlorate of campeen, or of dadyl, is beat obtained by passing dry hydrochloric acid gas into artificially cooled oil of turpentine until absorption ceases. If the pro duct be exposed to a freezing mixture of snow and salt, it soon becomes half filled with white prismatic crystals, having the characteristic aro matic smell and taste of camphor. They are insoluble in water, soluble in alcohol or ether, fuse at 239' Fehr., and boil at 329', undergoing partial decomposition. The liquid portion of the above product is also a monohydrochlorate, having the same composition as the solid ; it is termed hydrochlomte of pencyl, or of terebilen, inasmuch as that when distilled with quicklime it furnishes pencyl or terebilen, a liquid hydro carbon isomeric with oil of turpentine, but possessing no rotatory power on polarised light. The solid hydrochlorate by similar treat
ment yields camphen, camphilen, or dada!, also isomeric with oil of turpentine ; 273° Fahr. A solid and liquid biehlorhydrate of turpentine 21ICI), artificial lemon or citron camphor, are formed when oil of turpentine or of lemons is placed In contact with excess of strong aqueous hydrochloric acid for several weeks. A liquid suldrydrochlorate has also been obtained. Hydrobromie and hydriodie acids form compounds with oil of turpentine somewhat resembling the hydrochlorates.
Chlorine attacks oil of turpentine, and yields a guadriehlorinated derivative The Latter furnishes a biehlomnated compound on being heated. A euedribrominaled oil (C.II„Br,1 has also been obtained. Tereben and chlorine give a colourless viscid liquid, termed chlorotereben, and artificial camphor and chlorine yield crystals of chlorocamplien, Oil of turpentine is very susceptible of oxidation. The sponta neous production of resins from it has already been alluded to. By distillation with biehromate of potash and sulphuric acid it yields abundance of formic acid, and when gently heated with oxide of lead gives formic acid and tcretinic acid The latter crystallises to acieular tufts, and forms salts that, like itself, are insoluble in water but soluble in alcohol. A small quantity of oil of turpentine placed in a jar of oxygen gas standing over water and exposed to sunlight, rapidly absorbs the oxygen, and yields crystals of hydrated oxide of turpentine 2110). which are deposited on the sides of the vessel ; it Is soluble in alcohol, ether, and boiling-water. Strong nitric acid acts very violently upon oil of turpentine, the temperature fre quently rising high enough to cause inflammation of the mixture. When diluted, however, nitrio acid merely resinifiea the oil, and pro duces, among other substances, terebie acid, which will presently be described in detail in connection with resin ; terephthalic acid isomeric with phthalic acid (Narnanntso Gnoer]; terebenzic acid fusible at 336' Fahr., and sublimable like benzoic acid ; and terechrystc add of golden yellow colour, unerystallisable, and very soluble in water.