110 THE ANALYST. NOTE ON CHINESE TALLOW-SEED OIL. BY L. MYDDELTON NASH, F.I.C. (Read at the Meeting, February 3, 1904.) CHINESE tallow-seed oil is obtained from the seeds of Sapium sebiferum (syn. Stdlingia sebifera), a tree of the natural order Euphorbiacea This tree, which is indigenous to China and the adjacent islands, is known as the “tallow-tree.” It has been found to grow well in North India, and has also been introduced into South Carolina. Its leaves are about 2 inches broad, rhomboid-shaped, sharply tapering, and pointed ; they are attached to slender stalks, and have two prominent glands situated at the point of attachment between the stalk and leaf; its flower catkins are from 2 to 4 inches long. The fruit is about 8 inch in diameter, and contains three seeds thickly coated with a fatty substance, which yields the tallow.The hard wood of the tree is used by the Chinese for printing-blocks, and its leaves yield a black dye-stuff. The vegetable tallow, known to the natives as c c pi-yu,” is commonly extracted by the following method : The kernels, after being carefully removed from the hard outer shells, are placed in a large wooden drum provided with a number of holes. A current of steam is passed through the drum, when the melted tallow runs out into a receptacle placed beneath it. After the tallow has solidified it is again melted, filtered, and cut into cakes weighing about 1 hundredweight each, in which form i t is exported to Europe.THE ANALYST. 111 6 b Tee-ieou” or (‘ ting-yu” is the name given to the oil extracted by expression from the kernels left after the operation just described, and is 8 liquid oil with drying properties.I t is used as an illuminant and in the manufacture of varnish. pi-yu ” and (‘ ting-yu,” obtained from the whole seeds by a combination of the above process. mou-idou ” and b b pi-yu ” are sold under the name of Chinese vegetable-tallow, but the former is not so hard or white as the latter. The sample of tallow-seed oil which I examined is of a brown colonr, and has an odour resembling that of wood oil. Its viscosity, measured at 15.5” C., is about three-fifths that of rape oil. When cooled to 0” C. no stearine is deposited. A film of the oil on glass becomes nearly dry in three days and quite hard in The following results were obtained from the examination of the sample : The yield of oil is about 59.5 per cont.“ Mou-iQou ” is a mixture of Both six days ; it must therefore be classed among the drying oils. ... ... ... Specific gravity at 15.5’ C. 15-5’ C. Free fatty acids (as oleic) ... ... ... Unsaponifiable matter ... ... ... ... Saponification equivalent ... ... ... Iodine absorption (Hubl) ... ... ... Iodine absorption of fatty acids ... ... Hehner number ... ... ... ... ... Ineoluble fatty acids ... ... ... ... Combining weight of fatty acids ... ... Rotatory power (in 100-millimetre tube) about ul, Zeiss-butyro figure at 20’ C. ... ... ... Refractive index Y,, at 20” C. ... ... ... ... 0.9395 ... 3.1 per cent. ... 0.44 ,, ... 277 ... 160.7 ... 165 ... 94.4 ... 272 ... - 4 O ... 89.1 ...1.4835 ... 93-96 per cent. The fatty acids on cooling and standing separate into a solid and a liquid portion. The oil gives no very distinctive colour reaction with sulphuric acid. One drop of the concentrated acid on 20 drops of the oil gives a red-brown coloration, changing, on stirring, to a muddy-brown, and finally to ;L very dark brown. I n conclusion, I have to express my indebtedness to Professor Dunstan, F.R.S., director of the Imperial Institute, for kindly supplying me with the information aa to the botanical origin and method of producing the oil contained in this paper. DISCUSSION. Dr. LEWKOWITSCH said that the earliest paper on the subject of this oil was one published some years ago by Tortelli and Ruggeri, who named the oil (‘ Stillingia oil,” a name he had adopted in his “Laboratory Companion.” Those observers had recorded the laevo-rotatory property of the oil, and he was glad to find this confirmed now by Mr.Nash, because it was one of the most important characteristics of the oil. sample of the mixed fatty acids of the oil, which showed an iodine value of 181.8, a considerably higher figure than that given by Mr. Nash. The liquid fatty acids, freed from the solid portion, had the iodine value 191.1. These figures indicated Mr. Nash had been kind enough to afford him the opportunity of examining112 THE ANALYST. that the oil was one of high drying power, and, therefore, one which might very well be substituted for linseed oil when the latter should become dearer. The high iodine value, he had found, could not be due to any error, since he had it confirmed by what he ventured to call the (' hexabromide test "-ie., the amount of hexabromides obtain- able on treatment of the liquid fatty acids with bromine.The Stillingia oil acids yielded 25.78 per cent. of hexabromide, a proportion which was hitherto regarded as a maximum for linseed oil, though he (Dr. Lewkowitsch) had found the latter to yield as much as 40 per cent. The divergent results hitherto recorded for Chinese vegetable tallow were probably to be accounted for by the practice of selling not only the solid tallow and the liquid oil separately, but also a mixture of the two ; so that a, sample described as a vegetable tallow from China might be either the solid tallow or any product intermediate between it and the oil.In view of this, it might be interesting to mention that in the case of the solid tallow the iodine value was about 20. The figures of 50 or thereabouts whioh were on record probably referred to mixtures of the solid tallow and the oil. Mr. HERBERT E. BURGESS suggested that, since optical activity was very unusual in fatty oils, it might be worth while to steam-distil the oil and examine the fractions with a view to ascertaining to what the la3vo-rotatory power might be due. It was to be noted that the oil had a distinct scent. The PRESIDENT inquired whether the refraction figures given were obtained with the simple form of instrument specially designed for butter examination, or with the more complete instrument that could be used for a greater variety of work. Mr. NASH, in reply, said that possibly the difference in the iodine numbers might be due to the use by Dr. Lewkowitsch of Wijs's process, whereas he (Mr. Nash) had used the old-fashioned Hu bl process. Steam distillation would probably afford in- teresting results, but that the quantity of the oil at present at his disposal was too limited for the purpose. The refractometers (which had been kindly lent to him by Mr. Burgess) mere (1) a form of the Abbe refractometer, very similar to the ordinary Zeise butyro-refractometer, its readings, however, being in terms of the actual refrac- tive index, and (2) the Zeiss butyro-refractometer itself.