434 NICOTINE. 



conine and water. Treated with sodium, it is also 

 converted into conine. 



2. Nicotine. 



Occurrence. In the leaves and seed of the tobacco 

 species in varying quantity ; in poor qualities of tobacco 

 as much as 7 and 8 per cent., in Havana tobacco only 

 2 per cent. 



Preparation. Tobacco leaves are digested repeatedly 

 with water containing sulphuric acid, pressed, and the 

 liquid evaporated half down. It is then distilled with 

 caustic potassa, and the nicotine exhausted from the 

 distillate by ether. The ether is removed from the 

 ethereal solution by evaporating, finally elevating the 

 temperature to 140. The nicotine, which is still im- 

 pure, of a brown color, is distilled at 180 in a cur- 

 rent of dry hydrogen over quicklime. 



Properties. Colorless liquid of a weak odor; when 

 heated, of a suffocating tobacco-odor ; specific gravity, 

 1.048 ; soluble in water, alcohol, and ether. Boils at 

 250 with partial decomposition ; can, however, be 

 slowly distilled over, even at 146. Has an alkaline 

 reaction ; turns brown, and is decomposed in contact 

 with the air. Exceedingly poisonous. Diatomic base. 



The salts are easily soluble, and crystallize with diffi- 

 culty. The free base as well as its salts give crystal- 

 lizing compounds with iodine, bromine, and metallic 

 salts. 



Nicotine hydrochloro-chloromer curate, 



C 10 H 14 mHCl + 4HgCP, is obtained by adding an ex- 

 cess of a solution of corrosive sublimate to a solution 

 of nicotine, neutralized with hydrochloric acid. Crys- 

 tallizes from water in colorless, radiating groups of 

 needles. Nicotine chloromercurate, C 10 H 14 P + 3HgCl 2 , 

 crystallizes in large prisms, when sufficient of a solu- 

 tion of corrosive sublimate is added to a dilute solu- 

 tion of nicotine hydrochlorate to just cause it to re- 

 main turbid. 



