6 JOURNAL OF THE 



much of the heptane remaining unattacked ; and much having to 

 be rejected as boiling too high. The amounts of heptane bromi- 

 nated at one time varied from 100 to 300 grams, and the bro- 

 mine usually dropped in as fast as it could be absorbed by the 

 hot heptane. No quantitative data were preserved of these 

 experiments, however. The vield is seriously unsatisfactorv 

 with so expensive a material as the heptane. 



The following experiments were quantitative and conducted 

 with especial care: 



I. 100 grains of pure heptane and 160 grams of bromine. — 

 The heptane was kept boiling gently over a naked flame. The 

 flask containing it was provided with an inverted condenser and 

 a dropping funnel for the bromine. The bromine dropped in 

 the liquid, keeping it orange-red in color. The operation re- 

 quired five hours. The heavy oil was then washed with dilute 

 sodium carbonate, then with water, and finally dried over cal- 

 cium chloride. It was yellow, with an orange tint. It was 

 fractionated twice under a diminished pressure of 18-20 inches of 

 mercury; then four times fractionated under ordinary pressure. 

 The divisions were as follows: 



Fraction I, 100°-120°, nearly all under 110°, 30 grams; 



II, 120°-162°, 5 



III, 162°-168°, mainly 164°-167°, 55 



IV, 168°-173°, 2 

 V, 173°-183°, mainly between 176°-180°, 8 



VI, 183°-210° 10 



Probably one-fourth, in bulk, of the oil was left partly charred 

 in the fractionating flasks. 



II. 100 grains of pure heptane and 160 grams of bromine. — 

 The same apparatus as above was used, only the dropping fun- 

 nel was drawn out to a capillary and about half an inch of this 

 was submerged under the heptane. The bromine entered thus 

 slowly and in the form of vapor. The heptane was at first at a 

 lower temperature than in the first experiment. The tempera- 



