588 PROCEEDINGS OP THE AMERICAN ACADEMY. 



The filtered oil gave as its specific gravity at 20°, 0.85 G9. It gave 

 percentages of carbon and hydrogen requii'ed for the series CaH2a : — 



0.1504 grm. of the oil gave 0.4711 grm. CO2 and 0.1945 grm. HgO. 



Calculated for ,, . 



p TT p IT Found. 



C 85.70 85.18 85.41 



H 14.30 14.82 14.36 



The molecular weight was determined at the freezing point of benzol : 



3.464 grms. of the oil and 26.06 grms. benzol gave a rise of 1°.0475. 



Calculated for CjsHjg. Found. 



322 325 



The index of refraction was found to be 1.4714, from which was cal- 

 culated the molecular refraction ; — 



Calculated for CjjH^g. Found. 



105.87 105.31 



TeTRACOSANE, C24H50, AND LiQUID HYDROCARBON, C24H48. 



From Distillate 272°-274°, 50 mm. 



After the nineteenth distillation, 150 grams collected at 272°-274°, 

 50 mm., that became partly solid on standing. The decanted oil gave 

 as its specific gravity 0.8448 at 20°. A part of the distillate was then 

 cooled to —10°, and the solid filtered cold under pressure. 



The distillate was purified by treatment with successive portions of 

 fuming sulphuric acid, until the acid was nearly colorless, then washed 

 with sodic hydrate and a concentrated solution of calcic chloride, and 

 dried over fused calcic chloride and sodium. Nearly one third of the 

 volume was removed in purification. The purified oil then gave as its 

 specific gravity at 20°, 0.8598, and at higher temperatures: — 



60°, 0.8375 70°, 0.8366 80°, 0.8354 



A combustion of the purified oil gave percentages of carbon and 

 hydrogen required for the series CnHan. 



0.1539 grm. of the oil gave 0.4769 grm. CO2 and 0.2000 grm. H2O. 



