Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/805

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o la a "** 3 a S o"c 1 E gg A 3 1 8 o f ^ P3 !? "3 ^ J K-JI 6 Almond Reddish Reddish Olive Reddish 24 Grey White . . Orange yellow green white Castor Yellow Yellow Red Yellow 6-7 White . . White . . Orange ish j yellow Cod- Blood Violet Red Red .... Brown liver colour brown Cotton Orange Purple Red .... 20-24 Violet . . Brown Orange seed brown Ground Reddish Red Brown . . Reddish 24-30, Flesh Brown Yellow nut Hemp. . yellow Greenish yellow Dark yellow Green . . Black- colour Greenish Green Yellow- yellow brown ens yellow yellow ish Linseed Cadmi Purple Green . . Green Yellow green Yellow um yel brown brown low Madia . . Ruddy Dirty Dirty Yellow .. - browni ereen brown ish Mus Yellow Cherry Greenish Reddish 20 Yellow Brown tard ish red brown yellow ish ish (white) Olive .. Pale Dirty Greenish Greenish 1-2 White . . green Pale Orange green brown rose Poppy Yellow Green Brick . . Yellow- Clear red brown red ish brown Rape Brown Green Reddish 20 White . . Yellow Brown (refined) Sesame Yellow red Reddish brown Green . . yellow Green . . 20-24 Whitish ish Violet.. red brown Whale Dark Dark Dirty Red .... Reddish brown brown brown Commerce. As regards the United Kingdom it may be said in general terms that Hull is the centre of the linseed and other seed oil trade, Liverpool the headquarters of that in palm oil and palm- nut oil. Tallow and lard and sperm, train, and fish oils are dealt in principally in Dundee, London, and Greenock. In the Mediter ranean Marseilles and Trieste are oil -trad ing centres of great im portance, and Hamburg, Rotterdam, Antwerp, and Copenhagen are busy oil marts in northern Europe. Sperm oil, lard, and animal oils come to British markets most largely from the United States, tallow from South America and Russia, castor oil from the East Indies and Italy, olive oil from Italy, the south of France, and Mediterranean ports generally. Palm oil is received exclusively from the west coast of Africa, and cocoa-nut oil from the East Indies and Ceylon. Of seeds imported as sources of oil, linseed is principally derived from the East Indies and Russia, cotton seed from Egypt, and rape from Russia and the East Indies. The following table, from the Board of Trade Returns, gives the imports and exports of oils and fats into the United Kingdom for 1882 : IMPORTS. EXPORTS. Quantities. Value. Quantities. Value. 1. OILS AND FATS. Fish, train or blubber Sperm or head matter 14,303 tuns 1,642 tuns 67,877 cwts. 163,970 cwts. 133, 782 cwts. 23,450 tuns 813,870 cwts. 14,507 tuns 667, 153 cwts. 1,11(5,581 cwts. 35,538 cwts. 2,109,717 cwts. ! Produce of th Kingdo 2,433,132 qrs. 548,806 qrs. 209,689 tons 57,962 tons 120,963 qrs. 190,427 tons 420,466 111,197 157,617 264,551 210,054 947,154 1,240,866 476,807 116,229 1,866,360 2,252,517 129,926 11,350,909 e United ) ( 5,245,513 1,032,829 1,562,852 726,428 262,029 1,460,378 1,624 tuns 119 tuns 9,988 cwts. 24,288 cwts. 134,368 cwts. 3,668 tuns 428, 162 cwts. 1,162 tuns 43,682 cwts. 218, 852 cwts. 16,441 cwts. 85,249 cwts. 14,041,900 galls. 239,710 cwts. 6,050 qrs. 41,782 qrs. 64 tons 27,606 tons 90,280 qrs. 2,246 tons 49,082 9,053 25,714 40,057 205,788 166,693 642,203 37,279 20,175 127,258 428,460 55,074 478,963 1,444,071 372,229 13,179 100,895 543 330,877 201,543 : 14,732 Castor Olive Palm Seed (Jnenumerated Lard Tallow and stearin Wax Butter and butterine Oil (not essential or medicinal) Grease, tallow, and animal fat 2. OIL SEEDS, &c. Linseed Rape Nuts and kernels . . Oil seeds unenumer- ated Oil-seed cake Subjoined are notices of various oils and fats of considerable com mercial importance to which special articles are not devoted in other parts of this work. In several cases notices of oils will be found under special headings, incorporated with descriptions of other products of the plants and animals whence they are obtained. Here drying and non-drying oils are dealt with together in alpha betical order, after which vegetable fats and animal oils and fats are noticed in groups. 1. Liquid Vegetable Oils. Almond oil, the produce of both the sweet and the bitter almond, is a pale straw-coloured oil, having a pleasant nutty taste and sometimes when pressed from bitter almonds an odour of the essential oil of bitter almonds. The oil consists almost entirely of olein, remains fluid to -15 C., and solidifies at 20 C. It is used in food, and in medicine is employed as a demulcent and mild laxative ; but the readiness with which it becomes rancid interferes with its free use in these capacities. It produces a fine firm soap, and is also largely used by perfumers. The oil is much adulterated with the allied peach-kernel oil, and sesame oil, nut oil, &c. It is chiefly expressed in England from almonds imported from the Mediterranean and the East Indies. Peach-kernel oil (from Amygdaluspcrsica), Apricot oil (from Prunus armeniaca), Plum oil (from P. domestica), and Cherry oil (from the kernels of species of Cerasus) are a series of oils allied both in sources and properties frequently mixed with or sold as almond oil. Ben oil is obtained from the seeds of Moringn pterygosperma and M. aptera, trees native of Egypt, Syria, and the East Indies, and cultivated in America. The oil, cold-drawn, is clear, bland, and odourless, with little tendency to rancidity, but the product of final hot press ing is coloured, and has a bitter taste and purgative properties. The oil contains, in addition to palmitin, stearin, and olein, the glycerides of behenic acid C 2 oH 44 0. 2 , and myristic acid C^H.^O.j. Ben oil is used by perfumers for obtaining essential oils by enfleurage, as a hair oil and ointment, as a salad oil in the West Indies, and as a lubricant for watches and small machinery. It is, however, princi pally consumed in the regions of its production. Candle-nut oil is obtained from the nuts of Alcuritcs triloba, a tree native of the South Sea Islands, but grown also generally throughout tropical countries. The nuts are about the size of a horse-chestnut, with kernels which yield as nmch as from 60 to 66 per cent, of oil. The name given to these fruits is due to the fact that they are used in the Sandwich Islands, spitted on a stick, as lamps or candles, in which condition they burn with a clear steady light. The oil, cold-pressed, is a clear, almost colourless, rather viscid fluid, with a pleasant taste and smell, and medicinal properties akin to those of castor oil. Hot-pressed, it has a brown colour and a rather disagreeable odour and taste. It contains glycerides of linoleic acid and myristic acid in addition to those of palmitic acid and oleic acid, and possesses strong drying properties which make it useful for varnishes, and otherwise as a substitute for linseed oil ; it is also an excellent illuminant and a valuable soap-making material. On account of the cheapness of linseed oil, and the superior value of linseed cake, candle-nut oil does not find a very extensive market in Europe, but it is the basis of an industry of some importance in the South Sea Islands, whence a large quantity of the oil is annually exported to the west coast of America. The nuts of Alcuritcs cordata yield Wood oil, a power fully drying oil, of much importance in China and Japan for use as a natural varnish and in medicine. It does not enter into Western commerce. Cotton-seed oil, obtained from the decorticated seed of the varieties of cultivated cotton, is now, on account of the enormous extent of its production, one of the most important of the fluid vegetable oils. Its preparation is quite a recent industry, dating only from 1852, when the first importation of the material was made from Egypt. Since that period the trade has developed with extraordinary rapidity. Egyptian seed, containing about 25 per cent, of oil, is chiefly pressed in European countries (England, France, Germany) ; the American seed pressed in the United States shows not more than 20 per cent, of oil. The oil as expressed has a dark - brown turbid appearance, owing to the presence of a resin with albuminous impurities, and in the early days of the industry much difficulty was experienced in refining the product sufficiently for commercial purposes. It is now purified by as far as possible coagulating and separating the impurities by treatment with boiling water and steam. After the coagulum so formed has precipitated and been separated, the oil is treated with weak alka line ley, briskly agitated, and allowed to settle, when the coloured resinous matter goes to the bottom ; over that comes a proportion of saponified oil, and the clear refined oil forms the upper portion. The refined oil has a clear straw -yellow colour, a faint earthy odour, and a pleasant nut-like flavour. It consists entirely of a mixture of palmitin and olein, the former beginning to solidify and separate out between 12 C. and 6 C. There is no doubt that cotton-seed oil is very extensively and generally used to adulterate other and more costly oils, especially olive oil. It also is largely used in soap-making, and it constitutes a principal ingredient in compound lubricating oils. The quantity of cotton seed available for pressing annually is estimated to be not less than 800,000 tons, from which about 120,000 tons of oil and 250,000 tons of oil-cake may be produced. German Sesame or Cameline oil is procured from the small yellow or ruddy seeds of the cruciferous plant called Gold of Pleasure, Camclina sativa (Myagrum sativum, Linu.). The oil has a golden-yellow colour, a distinctive smell, and a somewhat sharp taste. In addition to other glycerides it contains that of erucasic acid, and of some analogue of linoleic acid. The oil dries XVII. 94