144 PROCEEDINGS OF THE AMEEICAN ACADEMY. 



"heaps" began to appear in the vicinity of 160°, 730 mm., falling off 

 below 158° and above 163°. These portions were therefore carried 

 through a long course of separations, fifty altogether, forty-five within 

 one degree, after which they collected mainly at 159°-162°. A com- 

 bustion of the crude distillate 159°-160°, purified as explained above 

 only by mercuric chloride, gave the following results : 



I. 0.1591 gram of the oil gave 0.4983 gram COo, and 0,2076 gram 

 HoO. 



Found. 



85.41 

 14.50 



On the basis of these values alone, there should be no hesitation in 

 assigning to this oil the formula CioHoq. The specific gravity of this dis- 

 tillate was found to to be 0.7717. Its vapor density was determined by 

 the Hofmann method : — 



0.1272 gram of the oil gave 67 c.c. of vapor at 182°, and under a ten- 

 sion of 374.4 mm. 



Calculated for CjoHj,. Found. 



4.92 4.96 



After treatment with ordinary concentrated sulphuric acid, another 

 portion of this distillate gave 0.7678 as its specific gravity, and the fol- 

 lowing percentages of carbon and hydrogen : — 



0.1416 gram of the oil gave 0.4452 gram CO,, and 0,1855 gram HoO. 



C 85.76 



H 14.56 



Agitation of the crude distillate in the cold with a mixture of concen- 

 trated nitric and suljihuric acids caused the separation of a heavy oil 

 that deposited crystals of a nitro product on standing. After crystalli- 

 zation from hot alcohol, in which it is sparingly soluble, this substance 

 melted at 229°, showing it to be trinitromesitylene, melting point 280°- 

 232°. Complete removal of the nitro compound from decane required 

 prolonged boiling with sodium followed by agitation with sulphuric acid. 

 The hydrocarbon then no longer attacked the metal, nor tarnished it on 

 long standing. Purified in this manner, this oil gave values required 

 for decane : — 



