OF ARTS AND SCIENCES. 219 



2. The separation of certain sulphides that do not correspond in 

 boiling points nor in composition with any sulphides hitherto described, 

 which will be further examined. 



3. The separation of certain sulphur free oils apparently unsatu- 

 rated that also require further study. 



I am not aware that these alkyl sulphides have hitherto been 

 identified as natural products. 



I. THE SULPHUR COMPOUNDS IN OHIO PETROLEUM. 

 By Charles F. Mabery and Albert W. Smith. 



When the various distillates from Ohio oils are agitated with con- 

 centrated sulphuric acid, the sulphur compounds are partially removed 

 in combination with the acid. By neutralizing the acid solution with 

 plumbic carbonate, filtering, and evaporating carefully, lead salts solu- 

 ble in water are obtained that are easily decomposed by heat with 

 the formation of plumbic sulphide. If the acid solution is neutralized 

 with calcic carbonate or calcic hydrate, unstable calcium salts are 

 formed that are readily decomposed by distillation with steam, which 

 carries over the sulphides without decomposition. 



In applying a mode of separation from the crude oil of the sulphur 

 compounds based upon these observations, we procured fifty litres of 

 what is technically known as sludge acid that had recently been used 

 in refining Lima burning oil, and after dilution we neutralized it in 

 the cold with slaked lime and distilled the mixture of solution and 

 solid with steam. We thus obtained 2,270 grams of the sulphur oil 

 that was colorless when freshly distilled, and entirely free from hydric 

 sulphide. Analysis showed that it contained 14.97% of sulphur 

 with a specific gravity at 16°. 5 of 0.9245. Analyses of samples of 

 crude Ohio oils from different localities have given on the average 

 about O.o0% of sulphur. 



Distillation under atmospheric pressure of the oil distilled with 

 steam produced such serious decomposition that we were forced to 

 conduct all fractional separations with diminished pressure ; but since 

 the decomposition was inappreciable at tensions reduced to 150 mm., 

 this involved but little additional labor, except in the inconvenience 

 of maintaining the required tensions with the use of common corks 

 without lutings, which became necessary on account of the solvent 

 action of the oil. The fractional distillations were carried on in the 

 apparatus represented in the accompanying diagram ; while it contains 

 no features not hitherto descrifjed, it may serve to illustrate how such 



