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The World's Commercial Products 



By permission of Messrs. Greenwood & Batley, Ltd. 

 SEED HEATING KETTLE AND HYDRAULIC CAKE-MOULDING MACHINE 



are subjected to the blast of a 

 fan to winnow out the skins 

 and packed in cloths for the 

 press. The oil is pressed out 

 once or twice in the cold before, 

 the meal is heated. The cold- 

 pressed oil is almost colourless, 

 has an agreeable taste and 

 smell, and serves as an edible 

 oil. The oil obtained by hot 

 expression is of a yellow colour 

 and is used in the manufacture 

 of soap. The residue is a valu- 

 able oil-cake that is used for 

 cattle-feeding purposes. 



Tea Seed Oil is a non- 

 drying oil prepared in China 

 and Japan, where it is used for 

 cooking and for illumination, 

 being derived from the seeds of 

 Camellia sasangua or Camellia 

 oleifera. 



Castor Oil is obtained 

 from the seeds of Ricinus 

 communis, related to the 

 Spurges, and most probably a 

 native of North Africa, but now widely distributed throughout the tropics and the warmer 

 temperate regions. It is cultivated in every continent, but the bulk of the world's supply 

 is produced in India, about 70,000 tons of seed and nearly two million gallons of oil being 

 annually available for export. In India a clear distinction is drawn between the commoner 

 large-seeded variety and the small-seeded variety, the former sometimes grown as a perennial, 

 the latter always treated as an annual. 



For medicine, as is generally known, cold-drawn oil is preferred. The fresh seeds, sifted 

 and cleaned from dust and debris, are crushed between rollers and packed in gunny cloth, 

 when they are lightly pressed to take the suitable brick form. The bricks, separated by iron 

 plates, are placed in a screw or hydraulic press, and the oil is collected in pans. Water is added 

 to the expressed oil, and the liquid is boiled until the water has evaporated ; by this means 

 the albumen is solidified and the mucilage subsides to the bottom. The oil is then filtered and 

 placed in cans for exportation. It. has a light straw colour. 



In addition to its value as a medicinal oil, castor oil was formerly used as an illuminant 

 in India, but is now chiefly employed in the manufacture of Turkey-red oil, required in the 

 dyeing and printing of cotton goods. ' The alizarine dyes, originally extracted from madder 

 root, but now prepared synthetically, require to be dissolved in a neutral fat or oil, which 

 besides dissolving the dye, must also penetrate the fabric. By treating castor oil with sulphuric 

 acid a suitable solvent is found that receives the name of Turkey-red oil. Formerly olive oil 

 was employed for the purpose, but it has been almost entirely replaced by castor oil. 



VEGETABLE FATS OR TALLOWS 



Palm Oil and Palm-kernel Oil. The well-known Oil Palm of the West Coast of Africa 

 (Elaeis guin'eensis) furnishes two different oils— a bright yellow or red-coloured substance of a 

 fatty consistence, palm oil, obtained from the fleshy outer covering of the fruits, and a white 

 oil yielded by the kernels of the seed. 



