MABERY. — SULPHUR PETROLEUMS. 31 



ren* separated a constituent of Pennsylvania petroleum distilling con- 

 stant at 11 9°. 5 (cor.), which gave a vapor density corresponding to 

 that of octane. From the extraordinary care with which the determi- 

 nations of Warren were made, there can be no doubt as to the 

 existence of a hydrocarbon with this boiling point in Pennsylvania 

 petroleum. Although hexahydroisoxylol has been recognized by 

 Beilstein and KurbatofF,t it is probably not the principal constituent 

 with tliis boiling point of the Pennsylvania oil ; it is certainly not of 

 the Ohio oil. 



From coal oil, Schorlemmer $ separated an octane boiling at 119°- 

 120°, and subsequently he identified the same body in petroleum 

 boiling at 119°. The followin<x data are taken from his original 



In the treatise on Chemistry by Roscoe and Schorlemmer, New 

 York, 1886, it is stated that the three octanes known are normal 

 octane, boiling point 125°. 46, found in petroleum; tetraraethylbutane, 

 boiling at 108°. 5 ; and hexamethylbutane, melting at 96°-97° and 

 boiling at 105°-106°. This enumeration does not recognize an 

 octane boiling at 119° in petroleum. It would seem that our fraction 

 from the Ohio oil was prepared with sufficient care to preclude the 

 possibility of a mixture of higher and lower constituents. We shall 

 endeavor to obtain independent evidence as to the identity of this 

 fraction by a study of its chemical reactions, and the preparation of its 

 derivatives. 



The following suggestion, which I have taken from one of the pri- 

 vate papers, dated 1868, of Mr. Warren, through the kindness of 

 Professor Storer, indicates that Warren recognized the possibility of 

 a series containing less hydrogen : "The samples analyzed may have 

 contained traces of more highly carbonized substances, and that it 

 would be worth while to treat with HOSOj and HONO5, and remove 

 these." Beilstein and KurbatofF met with the same difficulty in the 

 fractions 95°-100° and 118°-120° in their attempts to ascertain the 



* These Proceerlings, XXVII. 78. 



t Ber. der deutsch. chem. Gesellsch., 1880, p. 2028. 



t Journ. Chem. Soc, XV. 419. 



