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



caused, it was afterwards found, by a slight admixture of cymene was 

 noticeable. (Diagram 5.) 



Diagram 5. 



Oil of Indian geranium and two samples of the carraway hydrocarbon give the 



same spectrum. 



Cajuputene dihydrate exhibits the cymene absorption band at The lign aloe 



spectrum lengthens out very considerably, but feebly, at zwoo- 



The ordinates represent the proportions of alcoholic solution containing one 

 volume of the oils. Thickness of the layer of liquid = 15 millims. 



Oil of Lign Aloe. — This substance had no definite boiling-point, but 

 distilled over between 185° and 200°, leaving a thick yellow resin in 

 the retort. It was examined after diluting 1,000, 2,000, and 5,000 times. 

 (Diagram 5.) 



Carraway Hydrocarbon, No. 1. — This smelt like turpentine when dis- 

 tilled. The original label stated its specific gravity to be 0"8545. It 

 boiled between 173° and 178°. The solutions examined contained T oVo 

 and -50V0 volume of the liquid. (Diagram 5„) 



Oil of Indian Geranium, from Dr. Piesse. — This yielded the same 

 result precisely as the carraway hydrocarbon. It was not re-distilled. 

 (Diagram 5.) 



Otto of Rose, from Mr. Farries. — The specimen was solid and crystal- 

 lised in beautiful thin lamina. It was not re-distilled. Solutions 

 containing an d two of the volume of the melted substance were 

 examined. (Diagram 5.) 



"Santal Wood Oil Boiling-point 277°."* (Dr. Gladstone.)— The 

 first fraction obtained on distillation was returned to the original bottle. 

 The second part, which boiled between 277° and 287°, but chiefly be- 

 tween 277° and 280°, was the largest portion. The remainder distilled 

 between 287° and 297°. 



* Quotation from original label. 



