Dr. W. Ramsay on Picoline and its Derivatives. 31 



distilled between 280° and 310° ; but by far the largest por- 

 tion distilled between 310° and 320°. There was very little 

 remaining ; so that the fraction last mentioned constituted the 

 bulk of the oil. After two more distillations, the portion 

 boiling at 310-320° being collected separately, the base was 

 considered sufficiently pure for investigation. 

 Its vapour-density was determined twice: 



I.D= 



II. D: 



0-0420 gram x 1543500 x 14-47 



= 95-30. 

 0-0411 gram x 1543500 x 14-47 



= 97-99. 

 The theoretical vapour-density of dipicoline is 93. 

 Analysis of dipicoline dried over sodium and distilled :— 



Taken 0*2932 gram. 



G0 2 0*8313 gram, = 77-32 per cent. O. 



H 2 0-1886 gram, = 7-14 per cent. H. 



C 12 H 14 N" 2 contains 77-41 per cent, of carbon, and 7*52 per 

 cent, of hydrogen. 



Dipicoline, C 12 H 14 K 2 , is a yellow oil, closely resembling 

 dipyridine in appearance. Its smell is similar, but slightly 

 different. It mixes in all proportions with alcohol and ether, 

 and is sparingly soluble in water, to which it communicates 

 its taste and smell. Its specific gravity is 1-12, rather more 

 than that of dipyridine. It boils at 310-320° at the ordinary 

 pressure. It unites with acids to form salts which have little 

 tendency to crystallize. 



The hydrochloride, after standing in a syrupy condition 

 over sulphuric acid for some days, showed a tendency to 

 crystallize at the edge. The platinichloride has the formula 

 C 12 H u N 2 .2HCl.PtCl 4 . 

 Analyses : — 



I. Taken 0-5117 gram. 



Pt , 0-1692 gram, = 33-06 per cent. 



II. Taken 0*5069 gram. 



Pt 0-1684 gram, = 33-22 per cent. 



The platinichloride contains 33-73 per cent, of platinum. 

 Dipicoline unites with the iodides of the alcohol-radicals ; 

 of these compounds, the methyl-iodide was prepared. 



