336 FORESTRY INVESTIGATIONS V. S. DEPARTMENT OF AGRICULTURE. 



The crude turpentine from Phuis palastris, or long-leaf pine, is thus made up of— 



(1) Rosin, 75 to 90 pei cent; mostly abietic anhydride. 



(2) Anstralene, 25 to 10 per cent; boils at 153° to 156° C. 



(3) Some other teipenes of CaiH ft ; small portions; kind not known. 



(4) Somepoljterpenes of (C 5 Hh)ii; small portions ; kind not known. 



(5) Cymene (?) CmH u ; small portions, if any; boils at 175° to 176° C. 



(6) Traces of formic and acetic acids; produced probably by atmospheric oxidation during collection of 

 tuipentine. 



ANALYTICAL WORK. 



As both the rosin and the volatile oil are easily soluble in chloroform, ether, carbon clisulphide, 

 etc., their separation from wood by any of the above solvents would appear to be an easy matter. 

 But an exact quantitative determination of the volatile oil presents considerable difficulties, and 

 for these reasons: (1) Wood can not be dried free from moisture without driving off some of the 

 volatile hydrocarbons ; (2) the ether extract can not be freed entirely from either without some loss 

 of the volatile oil. 



If a weighed quantity of wood shavings is exhausted with either, the residue dried at 100° 0. 

 and weighed, the total loss thus found will represent: 



The moisture = IT. 



The rosin = R. 



The volatile hydrocarbons = T. 



It is sufficient to determine two of these factors; the third could then be determined by 

 difference. But as has been mentioned before, the ether extract can not be obtained m any degree 



b m 85 — Method of < hemu »1 unlysis of tnrp< ntuu 



of purity without loss of turpentine. The evaporation of ether in a stream of dry air, as proposed 

 by Dragendorf, for the estimation of essential oils in general, does not give satisfactory results 

 with turpentine oil, as Dragendorf himself observed. 



A weighed quantity of a mixture of rosin and oil, made up in about the same proportions as 

 they exist m crude turpentine, was dissolved in a suitable amount of ether. The latter was then 

 evaporated in a current of dry air till the odor of ether was hardly noticeable. The mixture was 

 found to have gained considerably in weight by retaining ether in the thick sirupy oleorosin. It 

 was only by heating at 100° O. for some time that all of the solvent could be driven off, and then 

 the mixture was found to have lost in weight. .Repeated trials proved that this method could not 

 be used safely. 



An attempt was then made to determine the quantities ZTand R, and thus find T by difference 

 A weighed quantity of wood shavings was placed in a small flask a. The latter was connected 

 on one side with a tray of drying bottles, on the other two CaCl 2 tubes b and c, similar in size 

 and form. The flask is immersed in boiling water and a current of dry air is passed through the 

 whole apparatus for one and one-half hours. The flask is then cooled and air is passed for one 

 and one-half hours longer. « 



It was thought that while b would retain all the moisture and a portion of the volatile com- 

 pounds, c would retain about the same amount of the volatile products only. Gain in weight of 



