40 BULLETIN 867, U. S. DEPARTMENT OF AGRICULTURE. 



The potassium soap of this oil is used as a solvent for water- 

 insoluble substances, as the ethereal oils, cresols, and synthetic 

 perfumes. 



The extensive use of castor oil in medicine is due to its purgative 

 property. Just to what this is due is a mooted question. Some think 

 that the presence of small amounts of ricine or some other impurity 

 imparts to the oil this property, which is lacking in the pure glycerid 

 or oil. Others claim that this property is characteristic of ricinoleic 

 acid (the acid radical of the oil) and quote in support of their con- 

 tention the fact that pure ricinoleic acid itself is purgative. On the 

 other hand, the statement that castor oil extracted from the seeds by 

 alcohol is more effective than that made by expression lends color to 

 the belief that the solvent plays a selective r61e in extracting more of 

 the substance which possesses the purgative property. 



Much effort has been expended in attempting to remove from castor 

 oil that property which makes it so repugnant to the taste and smell. 

 Simple deodorization in a vacuum deodorizer is not altogether 

 satisfactory. Everyone is conversant with • the corner druggist's 

 effort to mask it in soda water, peppermint, and other "sandwiches." 

 Coloring it and adding a tincture of some of the common spices is 

 about as satisfactory as any method. The following rather unique 

 concoction is quoted (J. King, King's American Dispensary) for the 

 reason that if such an unpleasant product as castor oil can be made 

 to simulate a custard, even remotely, the fact should be made known 

 to all: 



I find it a very pleasant mode of administration to boil the dose of oil "with about a 

 gill of good sweet milk for a few minutes, sweeten with loaf sugar and flavor with 

 essence of cinnamon or other favorite aromatic; it somewhat resembles custard in its 

 taste and appearance and is readily taken by even the most delicate stomach. 



CONCLUSIONS. 



It is thus seen that although castor oil is one of the minor oils, its 

 industrial use is increasing in a marked degree. While it is more 

 widely known for its medicinal properties, its use is being constantly 

 extended in a variety of industries. 



The general method of manufacturing the oil in this country has 

 been by crushing the beans in cage presses, but it has been found that 

 the expeller produces an oil of satisfactory quality for all industrial 

 uses and is perfectly satisfactory for aeroplane lubrication. Evidence 

 has been obtained that a good grade of No. 1 oil can be obtained by 

 extraction with volatile solvent. Highly acid dark oil can be refined 

 by alkali but not highly bleached, while low acid oils can be refined and 

 bleached to almost water white. Attention is called to the varied 

 uses made of the oil and the possibility of finding markets for the 

 more sluggish No. 3 oil. 



o 



