MABERY AND SHEPHERD. SOLID HYDROCARBONS. 285 



+ 



— K 



A 



■Ciif 



~-W 



This method was applied to the determination of the index of refrac- 

 tion of hydrocarbons separated from Pennsylvania petroleum direct as 

 described by one of us (Mabery) in a former paper, * and also to the 

 same hydrocarbons separated from commercial paraffine. The bodies 

 from crude petroleum had been distilled many times under a tension of 

 50 mm. and separated from the liquid hydrocarbons by cooling to a low 

 temperature, pressing out the liquid hydrocarbon, and crystallization of 

 the solids from ether and alcohol. 



* These Proceedings, XXXII. 365 (1902). 



