514 OLEAGINOUS PLANTS. 



of oil, of good quality, though amber-colored. 2. Expression is 

 the simplest and most usually adopted process ; the cleaned kernels 

 are well bruised, placed in cloth bags, and compressed in a powerful 

 lever and screw press. A thick oil is obtained, which must be 

 filtered through cloth and paper to separate the mucilage. In 

 Bengal the manufacturers boil the oil water, which coagulates 

 some albumen, and they subsequently filter through cloth, char- 

 coal, and paper. 3. The extraction by alcohol is practised by some 

 druggists. Each pound of paste is triturated with four pounds of 

 alcohol, specific gravity 8.350, and the mixture subjected to pres- 

 sure. The oil dissolved by the alcohol escapes very freely : one 

 half is recovered by the distillation of the spirit, the residue of the 

 distillation is boiled in a large quantity of water. The oil sepa- 

 rates and is removed, and gently heated to expel any adherent 

 moisture ; then filtered at the temperature of 90 deg. Fahrenheit ; 

 1,000 parts of the paste have by this process given 025 of colorless 

 and exceedingly sweet oil. 



The cultivation of the Palma christi, and the manufacture of 

 castor oil, is extensively carried on in some parts of the United 

 States, and continues on the increase. A single firm at St. Louis 

 has worked up 18,500 bushels of beans in four months, producing 

 17,750 gallons of oil, and it is stated that 800 barrels have been 

 sold, at 50 dollars per barrel. The oil may be prepared for burn- 

 ing, for machinery, soap, &c., and is also convertible into stearine. 

 It is more soluble in alcohol than lard-oil. 



American castor oil is imported for the most part from New 

 York and New Orleans, but some comes from our own possessions 

 in North America. In the United States, according to the " Ame- 

 rican Dispensatory," the cleansed seeds are gently heated in a 

 shallow iron reservoir, to render the oil liquid for easy expression, 

 and then compressed in a powerful screw press, by which a whitish 

 oily liquid is obtained, which is boiled with water in clean iron 

 boilers, and the impurities skimmed off as they rise to the surface. 

 The water dissolves the mucilage and starch, and the heat coagu- 

 lates the albumen, which forms a whitish layer between the oil 

 and water. The clear oil is now removed, and boiled w r ith a minute 

 portion of water until aqueous vapors cease to arise : by this pro- 

 cess an acrid volatile matter is got rid of. The oil is put into 

 barrels, and in this way is sent into the market. American oil 

 has the reputation of being adulterated with olive oil. Good seeds 

 yield about 25 per cent, of oil. A large proportion of the drug 

 consumed in the eastern section of the Union is derived by way 

 of New Orleans from Illinois and the neighbouring States, 

 where it is so abundant that it is sometimes used for burning in 

 lamps. 



In Jamaica the bruised seeds are boiled with water in an iron 

 pot, and the liquid kept constantly stirred. The oil which sepa- 

 rates swims on the top, mixed with a white froth, and is skimmed 

 off. The skimmings are heated in a small iron pot, and strained 

 through a cloth. When cold it is put in jars or bottles for use. 



