DESTRUCTIVE DISTILLATION OF ANIMAL SUBSTANCES. 469 



three hundred pounds no more than was suflBcient for the determination of its 

 constitution, and the leading characters of a few of its compounds. It is probable, 

 however, that some loss was incurred in the preliminary processes, as, from not 

 anticipating the presence of so volatile a base, I did not take any precautions for 

 producing complete condensation of the products, by means of freezing mixtures 

 or otherwise ; and a considerable quantity was also lost owing to my anxiety to 

 expel completely the ammonia which it might retain. 



Constitution of Petinine. 



The petinine employed for analysis was very carefully dried over caustic 

 potass, the fluid poured off after some days' contact, and distilled in the water- 

 bath at a very gentle heat ; a precaution which is rendered necessary by its dis- 

 solving a certain quantity of potass. I did not possess a sufficient quantity to 

 make a determination of the nitrogen, but took it for granted that oxygen was 

 absent ; an assumption which is justified by the analogy of all the other volatile 

 bases, as well as by the perfect coincidence of the experimental results with the 

 calculated formulae. It was analysed with oxide of copper in a very long tube, 

 and gave the following results : 



6"663 grains of petinine gave 

 16-286 ... carbonic acid, and 

 8-382 . . . water ; 



corresponding exactly with the formula C^ Hi,, N, as is shewn by the following 

 comparison : 



Calculation. 



66-66 

 13-88 

 19-44 



100-00 100-00 900-0 



In order to ascertain the atomic weight of petinine, I prepared its compound 

 with chloride of platinum, and made the following determinations of the platinum 

 contained in it : 



J f 6-351 grains of chloride of platinum and petinine gave 

 I 2-245 ••• platinum = 35-34 per cent. 



jy f 3860 grains of chloride of platinum and petinine gave 

 1 1-372 . . . platinum = 35-54 per cent. 



-..jj ( 2-844 grains of chloride of platinum and petinine gave 

 I 1-010 ... platinum = 35-51 per cent. 



