. Report upon the forestry investigations of the U. S. Department of agriculture. 1877-1898. Forests and forestry. 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 CaiHft ; small portions; kind not known. (4) Somepoljterpenes of (C5Hh)ii; small portions; kind not known. (5) Cymene (?) CmHu; small portions, if any; boils at 175° to 176° C. (6) Traces of formic a
. Report upon the forestry investigations of the U. S. Department of agriculture. 1877-1898. Forests and forestry. 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 CaiHft ; small portions; kind not known. (4) Somepoljterpenes of (C5Hh)ii; small portions; kind not known. (5) Cymene (?) CmHu; 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 u
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