164 Dr Anderson on the Properties of Picoline* 



When treated with chromic acid, even when very concen- 

 trated, and after boiling, no change takes place in the colour 

 of the solution, and only a small quantity of a yellow powder 

 is deposited; while aniline gives an abundant precipitate, 

 which has, according to the degree of concentration of the 

 fluid, a green, blue, or black colour. 



Picoline precipitates from solutions of chloride of copper 

 a portion of the oxide of copper, while the remaider forms a 

 pale blue solution, which, when evaporated to a small bulk, 

 deposits a congeries of prismatic crystals, which seem to be a 

 double salt. No blackening of the solution takes place, as is 

 the case with aniline. When an excess of hydrochloric acid is 

 present, there is obtained, on evaporation, another double salt 

 in large crystals, apparently derived from the rhombohedral 

 system. Picoline produces also double compounds with the 

 chlorides of mercury, platinum, gold, tin, and antimony. With 

 chloride of gold it gives an exceedingly characteristic com- 

 pound, in the form of a fine lemon-yellow precipitate, which 

 is soluble in a considerable quantity of boiling water, and is 

 deposited, on cooling, in delicate yellow needles. Aniline, 

 under similar circumstances, gives a reddish-brown precipi- 

 tate, resembling the ferrocyanide of copper. It gives, with 

 infusion of nut-galls, a copious curdy precipitate of a pale- 

 yellow colour, which dissolves in hot water, and is deposited 

 again on cooling. It does not precipitate the solutions of 

 nitrate of silver, chlorides of barium and strontium, or sul- 

 phate of magnesia. 



The properties of picoline, as now detailed, are obviously 

 different from those of aniline. They recalled, however, 

 strongly to my mind those of a base called Odorin, obtained 

 by Unverdorben* from Dippel's animal oil. According to this 

 chemist, Dippel's oil, which is obtained by several successive 

 distillations of the oleum cornu cervi, is a mixture of four dif- 

 ferent bases, to which he gives the names of Odorin, Animin, 

 Olanin, and Ammolin. Of these, the two first constitute nine- 

 teen twentieths of the whole oil, and the odorin, which resem- 

 bles picoline in its solubility in water, is obtained by simply 



* Poggendorf s Annalen, vol. xi. 



