20 



Prof. W. N. Hartley and A. K. Huntington. 



of the absorption exerted by this substance is extraordinary, and we 

 may no doubt regard it as being very nearly pure anethol or allyl- 

 phenol-methyl ether. (See Diagram 18.) 



Oil of Cassia (Dr. Gladstone). — This specimen began to distil at 

 130° C, but the thermometer rose at once to 250° and then slowly 

 continued upwards to 280°, the distillate being bright yellow. The 

 remaining portion was a brown resin. The portion boiling between 

 250° and 280° was dissolved in 1,000, 5,000, 50,000, 75,000, 100,000 y 

 and 150,000 parts of alcohol, and examined. (See Diagram 19.) 



DlAG-EAM 19. 



Oil of cassia. B.P. 250—280°. The absorption band is due to cinnamic 

 aldehyde, 9 H 7 OH. 



Absorption band rery faint at 150,000. 



The absorption is remarkably intense up to the dilution of 1 in 

 50,000, when a band of rays is transmitted adjacent to the position of 



