ELISHA MITCHELL SCIENTIFIC SOCIETY. 7 



ture had to be increased later on, but, so far as possible, all excess 

 over that necessary for the absorption of the bromine was 

 avoided. The time consumed by the reaction was about thirteen 

 hours. The oil was then treated as above. It was redder in 

 color. It was fractionated as above, only one time less under 

 ordinary pressure. 



Fraction I, 100°-120°, mainly under 110°, 35 grams; 

 II, 120°-162°, 5 



III, 162°-168°, mainly 1(U -167°, 25 



IV, 168°-173°, 6 

 V, 173°-183°, mainly 176°-180° 20 



No higher fraction than V was taken, though several grams 

 could have been gotten by carrying the residue on to partial 

 charring. Fraction V was in this case much more stable than 

 the corresponding fraction in the first experiment. It did not 

 turn brown so quickly, nor deposit black spots on the glass. 



III. 50 grams of pure heptane and 80 grams of bromine. — 

 No heat was used in this case. The heptane was in a small 

 open Erlenmeyer flask which was set in a vessel of water. The 

 bromine was poured in in small amounts and shaken until dis- 

 solved in the heptane, giving it a deep red color. Then it was 

 allowed to stand in the light until only a yellow color remained. 

 The temperature averaged about 6° C. The duration of tin- 

 experiment was twenty-five days. The resulting oil was washed 

 as above. It was bright yellow in color. It was fractionated 

 once under diminished pressure and once under ordinary pres- 

 sure. The following fractions were obtained: 



Fraction I, 100°-120°, mainly under 110°, 12 grams; 



II, 120°-162°, 2 



III, 162°-173°, mainly 164°-167°, 4 



IV, 173°-183°, 7 



V, 183°- 11)5°, very little; 



VI, 195°-205°, 7 grams; 



VII, 205°-215°, 12 



VIII, 215°-230°, ' 



