408 



ODOKOGRAPHIA. 



70 per cent, instead of 75 per cent, alcohol, at a temperature of 

 . 20^ C. instead of 15^-5 C, and in the same proportion, viz., 1 to 

 6 parts by volume. AVest Indian santal-wood oil under similar 

 conditions only gives an opaque solution v/ith 50 to 70 parts 

 of alcohol. Cedar-wood oil is not even soluble in 100 parts of 70 

 per cent, alcohol, but it gives a clear solution with 10 volumes 

 of 90 per cent, alcohol. (We have never met with a lower sp. gr. 

 than 0"975 in the course of many years' practice. That figure 

 may therefore be taken as the lowest permissible sp. gr. of 

 normal santal-wood oil)." 



SP. GR. AT 15"^C. 



OPTICAL ROTATION 

 100 M.M. 



East Indian Santal-wood oil 



West Indian 



Virginia Cedar-wood oil 

 {Juniper us Virginiana) 



Ditto 



Ditto 



Ditto 



The higher sp. gr. of Indian distilled oil of santal is accounted 

 for by Michael Conroy,* by the fact that in India the process of 

 distillation adopted exposes the charge to the action of heat and 

 water for the prolonged period of 10 days and nights. In proof 

 of this explanation he placed one pint of English distilled oil of 

 known density (0-975) in a jar with about 5 gallons of water, and 

 kept the whole at a temperature of about 120^ E. for 10 days and 

 nights. The oil increased in viscosity, became darker in colour 

 and the sp. gr. increased from 0-975 to 0-989. The loss of oil in 

 the experiment was half an ounce. 



* Proc. Brit. Pharm. Conf., 15th Auijust, 1893. 



