TURPENTINK. 



TURPENTINE. 



4SS 



pentine properly to called. True turpentine I* really an oleo.resin, a 

 liquid of about the consistence of hooey. It flow* naturally, or by 

 incuuon. fnmi the wood of moat coniferous trees, such as pine, laroh, 

 fir, putechia. Ac., and by <litllltion yields spirit, essence, or volatile 

 oil of trpetitif, the nun-volatile portion being common rerin, or cola- 

 fkimy. I KESIKB.] Oil of turpentine is very largely used in the prepa- 

 ration of painta and varnishes, and also, when rectified, for burning in 

 lamps under the name of oamphin. The derivation of the word tur- 

 pentine is not very evident It was known and described by Marcus 

 Gnccus in the eighth century. 



The turpentine met with in English commerce is nearly all imported 

 from the State* of America, North Carolina and Virginia, supplying 

 the greater part. It is the produce of Pintu paltatnt, P. titda, and 

 P. atxet. French or Bordeaux turpentine is mainly obtained from 

 Pinxt maritima, a tree growing abundantly on the coast* of Southern 

 Europe. 



The method of procuring turpentine Is very simple. An incision, or 

 hole, is made in the bark of the tree, or a email piece of the bark is 

 removed, m the spring of the year. From this wound the turpentine 

 slowly exudes, and is collected either in a little trough attached to the 

 stem, in a hollow made at the foot of the tree, or by some similar con- 

 trivance. It is from time to time transferred to casks made to hold 

 about '2 cwt. The first gathering is sometimes called virgin turpentine. 

 and contains about 20 per cent of oil ; that collected towards the end 

 of the season, in October, has a more solid but still soft consistence, 

 and is not so rich in oil. As might be expected, the crude turpentine 

 frequently contains portions of twigs, chips, and leaves; these are 

 sometimes separated by straining the melted turpentine, and the latter 

 is then termed refined. Venice turpentine is the variety produced from 

 the larch tree (Larix Suroptea) ; Canadian turpentine, or Canada 

 baitam, exudes from the Abtet bnhamea ; and Chian turpentine is 

 obtained from the Piitaeia terebinths. 



Turpentine slowly hardens when exposed to the air. This is partly 

 due to evaporation of the more liquid portion, and partly to resinifica- 

 tion of the fluid part by oxidation. It is probable that in the tissues 

 of the plant turpentine is simply a mobile juice, and that in the ordi- 

 nary state of oleo-resin it is a product rather than a simple vegetable 

 educt. It softens and liquifies when heated, readily takes fir* in the 

 air, and burns with a somewhat smoky flame. It is completely dis- 

 solved by alcohol or ether, and by distillation with water yields oil of 

 turjientine. 



Oil of turpentine (C w H 16 ). As already indicated, this Is obtained 

 by distilling turpentine with water ; it then forms the upper layer of 

 the condensed product For most purposes it is re-distilled with 

 caustic alkali, acid matters and traces of resin being thereby removed. 



Oil of turpentine is a colourless mobile liquid, of characteristic odour 

 and hot pungent taste. It should be neutral to test-paper, of specific 

 gravity 0'86, boiling-point about 320 Fahr., and a vapour density of 

 476. It rotates a ray of polarised light, to the left or right according 

 to origin. It is very soluble in ether and absolute alcohol, less so in 

 ordinary (hydrated) alcohol, and is not miscible with water. It is a 

 good solvent of resins, oils, sulphur, phosphorus, and caoutchouc. 

 Pure turpentine, as obtained by re-distillation in vacuo, has constant, 

 well-defined, Ucvo-rotation. Berthelot distinguishes it as Imbrnthrn. 



Modifirationi and Deriratim of Oil of Turpentine. Under the influ- 

 ence of heat, or of chemical re agents, or of both combined, oil of tur- 

 pentine yields several interesting substances. Jioterebenthen is one of 

 the products into which oil of turpentine is resolved on heating, in a 

 closed vessel, to about 470 Fahr. It is a colourless liquid, having an 

 odour of stale lemons, sp. gr. 0*843 at 71 Fahr., boiling-point 350 

 Fahr , possesses Isovo-rotation of varying intensity on polarised light, 

 yields a solid hydrate and hydrochlorate. lUitaterebrnthcn, like isotere- 

 benthen, has the same composition as oil of turpentine ; it is formed 

 under the same circumstances as isoterebenthen, but remains in the 

 retort after the beat has been raised to 660* Fahr. It distils, however, 

 at a temperature slightly higher than 660, and then forms a yellowish, 

 very viscid liquid of sp. gr. 0-918 at 68 Fahr. It has a disagreeable 

 odnur, and exerts licvo rotation on polarised light. 



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 mass separates into two portions, and the upper clear liquid fur- 

 nishes, on distillation, a body having the same boiling-point and com- 

 position as the original oil, but of an odour resembling that of oil of 

 thyme : it is called tereben. Culophen is produced at the same time as 

 tereben ; its density, however, is twice as great, and its boiling-point is 

 between 660 and 600' Fahr. It may also be obtained from colophony, 

 hence 1U name. Neither tereben nor colophon has any action upon 

 polarised light 



Water combine! with oil of turpentine to form definite hydratet, of 

 which three are solid and one liquid. When the oil Is exposed to 

 intense cold, crystals of binhydraic (C,II .. 2HO) sometimes separate, 

 but generally a AaAjrrfra( (CL.H,., 6HO), called terpin, in largo 

 prifimalic crystals, i* deposited. The latter may be obtained In quan- 

 tity l>y well mixing four parts of oil of turpentine, one of niti 

 (sp. gr. 1 3d), and three of alcohol (sp. gr. 0-840), and setting aside for 

 tevenl w.-i-l; . When sublimed, the hexahydrate loses two equivalents 

 of water, and Is converted into a quadhydrate (C W H W 4HO). The 

 quadhydrate is also formed on exposing turpentine and water to a con- 



tinued heat of about 180* Fahr. It is more soluble in hot th.v 

 water, and is readily taken up by alcohol, ether, or benzole. A fourth 

 hydrate, termed terpinol (C^Ji^. HO), which is a fluid atoornm. 

 peratures, is formed on distilling either of the other hydrate! with water 

 containing a little hydrochloric or sulphuric acid. It has on odour like 

 that of the hyacinth, boils at 384" Fahr., and is of sp. 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, nnd henoe are termed artificial camfkun. The 

 nonohydrochlorute (C. H I(1 , HC1), called also hydrochlorate of camphen, 

 or nf dadt/l, is best obtained by passing dry hydrochloric arid 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 Fahr., 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 hydrochlorate of pencyl, or of terebilen, inasmuch as that when 

 distilled with quicklime it furnishes pencyl or terebilen, a liquid 1 

 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 tiatli/l, also isomeric with oil of 

 turpentine ; boiling-point, 278 Fahr. A solid and liquid biclilor/iydrate 

 of turpentine (C, H 1(V , 2HC1), artificial lemon or cifron camp/iur, 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 

 lubhydroehlorate ^C^M,,, HC1) has also been obtained. Hydrobromic 

 and hydriodic acids form compounds with oil of turpentine somewhat 

 resembling the hydrochlorates. 



Chlorine attacks oil of turpentine, and yields a quadrirldorlnateA 

 derivative (C TO H,,C1 4 ). The latter furnishes a bicklorinnttd compound 

 (C (0 H 14 C1,) on being heated. A auadribrominated oil (CjoH^Br,) has 

 also been obtained. Tereben and chlorine give a colourless viscid 

 liquid, termed clilorotercben,&nA artificial camphor and chloric, 

 crystals of chlorocamphen, 



Oil of turpentine is very susceptible of oxidation. The sponta- 

 neous production of resins from it has already been alluded to. I'.y 

 distillation with bichromate of potash and sulphuric acid it yields 

 abundance of formic acid, and when gently heated with oxide of lead 

 gives formic acid and teretinic acid (C,,H U O 10 ). The latter crystallises 

 in acicular tufts, and forms salts that, like itself, are insoluble in water 

 but soluble in alcohol. A small quantity of oil of turpentine plan d 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 (C^H^O,, 2HO). 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 temperate i 

 quently rising high enough to cause inflammation nf the m 

 \Vhen diluted, however, nitric acid merely resinifies the oil, atid i>'"- 

 duces, among other substances, terebic acid, which will presently l>e 

 described in detail in connection with resin ; terrplithalic acid (C, e H e O,) 

 isomeric with phthalic acid [NAPHTIULIC GBOVP] ; trrrticn;i<: acid 

 (C,,H,O t ?), fusible at 336 Fahr., and sublimable like benzoic acid ; and 

 terechryttc acid (C lt H O,), of golden yellow colour, uncrystallisable, and 

 very soluble in water. 



The chief properties of the non-volatile or resinous constituents 

 the rerin of turpentine have already been described. [RESINS ] It 

 now therefore remains only to notice the relations of the constituents 

 individually, and shortly describe their derivatives. 



Turpentine Ketin, as a whole, ia acid, and has the com]> 

 (HO, C^HjpO,). In reality, however, it contains three <i. 

 Isomeric with each other, but having dissimilar physical pMj . 

 their names are pimaric, y Ivic, and pinic acids. The two lati- 

 no doubt, mere modifications of the first, and probably owe their dis- 

 similarity to the action of heat. Pimaric add is best obtained from 

 the white resin or galipot of Bordeaux turpentine. The resin is pow- 

 dered, digested in a mixture of BIX parts of cold al.-..ln.l .md one of 

 etluT, which separates matters other than |ninaric acid, and the residue 

 is finally boiled with alcohol. On standing for a few days, the solution 

 deposits crystalline tufts of the acid under consideration. It 

 xnliiUe in ether and hot alcohol, less so in cold alcohol. It fuses at 

 257 Fahr., but does not re-solidify till cooled down to 1 54 Fahr. Tho 

 fused acid is clear and transparent as glass ; when powdered it. i. 

 perfectly dissolved in Its own weight of alcohol, Imt in a few minutes 

 the solution begins to deposit elli] K which, like tli 



fused acid, require ten times their weight of alcohol for solution. By 

 distillation in vacuo pimaric acid furnishes svlvic acid, at first thought 

 to be new, anil called nyromaric a<W. >'_</'> '"' nfi<l may ho obtained 

 from powdered resin. The latter is well washed with cold alcohol to 

 remove pinic acid, and the residue dissolved in boiling alcohol ; on 

 standing, the sylvic acid crystallises out Its crystalline character is 

 i uiiounced than that of pimaric acid ; in other respects the two 

 mueh resemble each other. Pinif acid, or the amorphous resin o 

 colophony, is obtained on evaporating the mother liquor from the pre- 

 paration of sylvic acid ; by heat it is partially decomposed, and changed 

 to another Isomer, cotoMouo </ itl. 



By destructive distillation at a low temperature, turpentine resin 



