CYANOGEN. i>83 



Nicotine exists in the leaves and seed of different species of 

 tobacco, namely Nicotiana tabacum and Nicotiana rustica. It 

 is soluble in water, has the consistence of butter and distils 

 at 284. 



Pelosine in the root of Cissampelos pareira. 



Solanine in several species of Solanum, and in the first shoots 

 of germinating potatoes. 



The following bases are not so well known and still proble- 

 matical : apirine, azaridine, blanchinine, buxine, carapine, 

 castine, chioccine, crotonine, cynapine, daphnine, digitaline, 

 esenbeckine, eupatorine, euphorbiine, fumarine, glancine, glau- 

 copicrine, jamaicine, menispermine, paramenispermine, pitayine, 

 sanguinarine, staphisaine, surinamine, violine. Besides two 

 bases in Carthagena quinquina bark and in chinova bark. 

 (Liebig.; 



CHAPTER X. 



CYANOGEN AND ITS COMPOUNDS. 



Cyanogen, NC 2 =Cy, which, when free, is a gas (page 428), 

 is remarkable as an organic radical, and enters as a constituent 

 into a large class of compounds. It combines directly with 

 hydrogen, forming a hydrogen-acid, with the whole of the 

 metals forming salts, and is also obtained in combination with 

 oxygen forming several acids, and with chlorine. Cyanogen 

 also appears to be a constituent of urea and uric acid, and of 

 the numerous bodies derived from the decomposition of the 

 latter. 



Formation of cyanogen. ~ This compound is always primarily 

 obtained as a constituent of ferrocyanide of potassium (page 

 450). In order to explain the reaction between animal matters 

 and carbonate of potash, when fused together at a red heat, 

 which gives rise to that salt, it is necessary to keep in mind the 

 following properties of the salt : When heated to redness in a 

 close vessel, ferrocyanide of potassium is decomposed into 

 cyanide of potassium, carburet of iron and nitrogen gas ; that is, 



