the; journal of pharmacology. 253 



C 10 H 16 O, and geraniol, B 10 H 18 O. Citral, the source of the lemon odor, 

 can be isolated by taking advantage of the fact that it forms a compound 

 with sodium bisulphite ; and geraniol, the alcohol from which originates 

 the rosedike odor of the oil of citronella; oil of geranium and otto of roses 

 may be identified by the formation of a solid compound with calcium 

 chloride. Besides this, another alcohol, isomeric with geraniol, has been 

 isolated, namely linalool. This alcohol is found associated with geraniol, 

 in many essential oils, and when present either in the free state or in the 

 •ester of acetic or of valerianic acid, is the source of the sweet odor of oil 

 of linaloe, oil of lavender and oil of bergamot. Derivatives of these two 

 alcohols are also present in oil of sassafras leaves, in the form of their 

 acetic and valerianic esters. Apart from these highly aromatic principles 

 the oil also contains several terpenes, namely pinene and phellandrene, 

 considerably more of the latter than is present in the bark oil ; there is 

 also, apparently a considerable amount of some hydrocarbon, C x oHj 6 , which 

 belongs to the "aliphatic terpene " class. These bodies are highly in- 

 teresting, but so far have not been completely investigated. They are 

 hydrocarbons with an open chain of carbon atoms containing three 

 double bonds, and are characterized by a low specific gravity, high refrac- 

 tive power (compared with ordinary terpenes) and excessive tendency to 

 polymerize. This peculiarity renders their investigation very difficult. 

 It is not unlikely that they form the mother substance of quite a number 

 of other constituents of essential oils. In the highest boiling parts of sas- 

 safras leaf oil, some cardinene seems to be present and also a paraffin-like 

 substance melting at 58 C. Such paraffins are often found in oils distilled 

 from leaves, as in oil of gaultheria and otto of roses ; the latter contains 

 so large an amount that the paraffins crystallize out at even a moderate 

 temperature. 



Reviewing this enumeration of the chemical constituents of the two oils 

 from sassafras, we find therein a striking and interesting example of the 

 ability of some plants to produce in their various parts, oils which are 

 fundamentally different in their chemical composition. It would be very 

 desirable if extended researches in this direction could be made with other 

 aromatic plants, as such investigations would probably throw some light 

 upon the question which so far has been found unanswerable : How does 

 the plant produce the great variety of complicated substances, the mixture 

 of which constitutes its essential oils ? 



