Calculation. 





77-92 



C,o 



240 



7-79 



H 24 



24 



9-09 



N 2 



28 



5-13 



o 2 



16 



PRODUCED BY DISTILLATION OF CINCHONINE. 315 



I. II. 



Carbon, 7734 



Hydrogen, 8-09 7"80 



Nitrogen, 

 Oxygen, 



308 



The fact of the two series of bases present not being homologous with each 

 other, rendered a considerable amount of labour necessary before they could be 

 purified sufficiently for analysis, the presence, in very small quantity, of a base 

 of the one series altering to such an extent the composition of the other, that no 

 confidence could be placed in an analysis, unless extreme care was taken in the 

 purifications, and the small amount of material at my command naturally added 

 considerably to the difficulties with which I had to contend. 



Lutidine — It soon became evident that the third base discovered by Dr Ander- 

 son in the animal oil of Dippel, and to which he gave the name of lutidine, was 

 that which most prominently presented itself in the first fractions. It was 

 subsequently ascertained that pyridine and picoline were present in exceed- 

 ingly small quantities, and to attempt their isolation would have been useless. 

 The only evidence I have to show of the presence of pyridine is an isolated result, 

 being the composition of the second crop of crystals of platinum salt obtained 

 from the first fraction duringthe earlier rectifications, and before the pyridine could 

 have escaped, as being present in such small quantity it was sure to do event- 

 ually, from the difficulty of effecting perfect condensation in an operation invol- 

 ving the changing of the receiver every few minutes. 



2*740 grains of platinum salt, second crop, from fraction boiling below 330° F. (165° C.)' 

 (fourth distillation) gave 

 ■948 grains of platinum, 



or 34- 6 per cent. 



Experiment. Theory. (Pyridine.) 



34-6 34-6 



The difficulty experienced in obtaining the lutidine sufficiently free from the 

 bases above it, to enable a good result to be obtained, will appear from the ana- 

 lyses below, which were made upon platinum salts from fractions which had been 

 rectified the number of times prefixed to each result. 



1st Rect. 2d Rect. 4th Rect. 



Carbon, . . 29 40 28-89 27*10 27-20 



Hydrogen, . . 373 384 3-30 3-28 



Platinum, . . 3085 3063 30-83 



It was evident, therefore, that although the numbers were gradually becoming 

 nearer to those required for lutidine, that, nevertheless, many more rectifications, 

 would be necessary before any close approximation could be expected. The 

 small quantity of fluid was therefore, with careful management, made to pass 



