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XIII. — On the Products of the Destructive Distillation of Animal Substances. 

 Part III. By Thomas Anderson, M.D., Regius Professor of Chemistry in 

 the University of Glasgow. 



(Read 17th April 1854.) 



In the preceding parts of the investigation of the products obtained by the 

 destructive distillation of animal substances, I have entered fully into the method 

 of treating the raw material, and have shown the existence in it of not less than 

 three different series of bases ; one, that of which methylamine is the type ; a 

 second, of which picoline is an example ; and a third series, not yet further exa- 

 mined, to which the provisional name of pyrol bases has been applied. Besides 

 these, aniline is also met with, but whether as an isolated substance or accompa- 

 nied by the other members of its series, cannot be determined, as none of them 

 possess sufficiently distinctive reactions to permit their detection in a complex 

 mixture. 



To the series of which picoline is a member my attention has hitherto been 

 specially directed, and chiefly owing to the interest attaching to these bases from 

 their identity in composition with the corresponding members of the aniline series, 

 aniline and picoline being the first instance in which the isomerism of two organic 

 bases, of which we have now so many examples, was distinctly made out. In 

 the second part of the investigation, three members of the series in question are 

 described, namely — 



Pyridine, C 10 H. N 



Picoline, C 12 H 7 N 



Lutidine, . . . • . C u H 9 N 



of which the two latter are isomeric with aniline and toluidine. It was further 

 remarked, that the phenomena observed seemed to indicate that the members of 

 this series present in Dippel's oil, did not terminate with lutidine, but that bases 

 of higher atomic weight and boiling point manifestly existed in it. The object of 

 the present paper is to show that this statement was well founded, by giving a 

 description of another member of the series, and further to define their true con- 

 stitution. 



On pursuing the distillation of the different fractions of basic products obtained 

 by the process described in the second part of this investigation, and distilling at 

 temperatures above 305°, which is about the boiling point of lutidine, it was found 

 that, when converted into platinum salts, the percentage of platinum gradually 

 diminished as the boiling point rose. Taking advantage of the well-known empirical 



VOL. XXI. TART I. 3 N 



