146 Dr. Anderson on the Products of the 



and have shown the existence in it of not less than three differ- 

 ent series of bases ; one, that of which niethylamine is the type ; 

 a second, of which picoline is an example ; and a third series, 

 not yet further examined, to which the provisional name of 

 pyrole bases has been applied. Besides these, aniline is also 

 met with, but whether as an isolated substance, or accompanied 

 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 5 N 

 Picoline . . . . C 12 H 7 N 

 Lutidine . . . . C 14 IPN 



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 Dippers 

 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 constitution. 



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 per-centage of platinum 

 gradually diminished as the boiling-point rose. Taking advan- 

 tage of the well-known empirical law, that the boiling-points of 

 homologous substances rise by 34° of Fahrenheit for every ad- 

 dition of C 2 H 2 to the atom, and from which the boiling-points 

 of pyridine, picoline, and lutidine do not greatly differ, I directed 

 my attention to the portion of mixed bases boiling about 340°, in 

 which it was reasonable to expect that the next base of the series 

 should be found. But even after repeated rectifications, the 

 base distilling at this temperature still gave a very powerful 

 reaction of aniline with chloride of lime, and the per-centage of 

 platinum in its double compound was but little lower than that 

 of the lutidine salt, or at all events never reached the number 



