mar 



^4Q RESEARCHES ON THE VOLATILE HYDROCARBONS. 



and five minutes later to 110°.8, at which point, having distilled nearly to dryness, the 

 operation was suspended. The corrections for pressure (— 0°.16) and for the upper 

 column of mercury — which, with the thermometer used in this experiment, was only 

 r in length, — gives 110\3 as the corrected boiling-point of toluole. Church* re- 



that toluole, when distilled in the ordinary manner, is liable to become oxidized, 

 and its boiling-point thereby raised, in consequence of the upper part of the retort 

 becoming heated above the boiling-point of toluole. He found that toluole which, by 

 ordinary distillation, had come over between 108° and 109°, would distil eight tenths 

 between 103° and 104°, after repeated purification with sodium. I would therefore 

 state that my preparation of toluole was never subjected to a temperature above its 

 boiling-point ; and that I have never noticed any reduction of the boiling-point of this 

 body by purification with sodium. 



Analysis. — 0.1628 gramme of toluole gave, by combustion in a stream of oxygen 



- 



gas, 0.5447 of carbonic acid, and 0.1315 of water. 



Calculated. Found. 



Carbon, C 14 84 91.3 91.20 



Hydrogen, Hg % 8.7 8.97 



92 100.0 100.17 



Determination of Vapor Density. 



Temperature of balance, 

 Temperature of oil bath, 



- . - - 17 

 209 



Height of barometer, . . . . M 760.1 mm - at 15 

 Increment of balloon, . 



Capacity of balloon, 



0.287 

 249.5 c. e. 



Density of vapor found, . 3.2196 



Theory C 14 H 8 = 4 volumes, , . 3.1822 



3. Xylole. ( Cumok of Mansfield and Ritthausen.) 



Specific gravity, 0.878 at 0°, and 0.866 at 15°.5. 



Determination of Boiling-point. — This determination was made in all respects like 

 that of benzole, the xylole employed having been also subjected to the same treat- 

 ment. The quantity operated upon was, however, smaller, and the experiment con- 



Philosophical Magazine, 1855 (4), IX. 256. 



