POSTSCRIPT. 



Although the analogy existing between picoline and the other oleaginous 

 bases is perfectly suflBcient to warrant the assumption of the absence of oxygen 

 in that substance, I have thought it advisable to append here an experimental 

 determination of the nitrogen. As the volatile bases cannot be readily analysed 

 by Vaerenteap and Will's method, I made a combustion of the platinmn salt, 

 and determined the proportion by volume of the carbonic acid and nitrogen in 

 four tubes, which gave the following results : — 



I. 94 volumes gave 8' nitrogen. 

 II. 240 ... 18- 



III. 84 ... 6-5 ... 



IV. 421 ... 35- 



839 67-5 



These results give the gases in the proportion of 11^ to 1 ; in other words, 

 they shew a slight excess over the theoretical result, according to which they 

 should be in the proportion of 12 to 1. They confirm perfectly, however, the 

 absence of oxygen. 



