448 



ODOKOGRAPHIA. 



Cheap Commercial Oils. 



NO. 



1 



2 



PHYSICAL PROPERTIES. 



FRACTION 

 150^-170^. 



^ . , ^ ^. 1 4o f 96 per cent. 1 



Optical rotation +14^1^^^^,^^^^^^.^^^^^^^ 



JSp.gr. 0-873 at lo^Cl / 95 per cent. | 

 [ Opt. rotation +4^ J I turpentine oil) 



/ Sp. gr. 0-868 1 

 [ Optically inactive / 



100 per cent 



turpentine oil 



the first 



acetic ethe 



were 

 her J 



FRACTIOX 



170^-185^ 



RESIDUE. 



1 per cent. 



per cent 



It is thought probaljle that besides borneol, other alcoholic 

 constituents may be present in some of the pine-needle oils, for 

 while in some instances it is easy to obtain borneol in a 

 crystalline state after saponification in quantity almost 

 corresponding to the amount of ester, in others it cannot be 

 isolated at all, or only in small proportion. 



On account of the interest attaching to bornyl-acetate, Messrs. 

 Bertram & Walbaum have prepared the ester artificially from both 

 Iffivo, and dextro-borneol. The lajvo-bornyl acetate corresponds in 

 all its characters with the natural ester.* The dextro-acetate is 

 distinguishable only by the rotatory power. In a pure state 

 bornyl acetate melts at 29^ C, and it crystallises from petroleum 

 spirit in rhombic crystals often an inch long. The borneol esters 

 of acids homologous with acetic acid, are very much like the 

 acetate in odour, Ijut it intensely increases with the molecule of 

 the acid constituent. It is probable that one or other of these 

 esters may be present in pine-needle oil, together with bornyl 

 acetate. 



* Series!., p. 342. 



