ANIMAL CHEMISTRY LECTURE II. 



Under a variety of circumstances both acetamide and aceto- 

 nitrile absorb the elements of water, with reconversion into acetate 

 of ammonia, a body containing the complete antagonistic mole- 

 cules, to which the constituent residues of the amide and nitrile 

 alike appertain. 



Acetat-ammonia 



60 



o = 



77 



CO 



Acet-amide 



60 



17 



- H 2 



- 18 



= C,H 5 NO 

 59 



Aceto -nitrile 



60 



H 3 N - 2H 2 



17 - 36 



C,H 3 N 



(27). Let me give you one additional illustration of this doc- 

 trine of residues. Upon applying a gentle heat to certain metallic 

 cyanides we obtain cyanogen gas, which is recognisable by the 

 beautiful violet-coloured flame with which it burns, as you see, 

 at the mouth of the tube. In this experiment the cyanogen is 

 being made by heating cyanide of silver, but it is capable of 

 being produced in an entirely different manner. For if, instead of 

 combining ammonia with acetic acid, we combine it with oxalic 

 acid, and if from the resulting oxalate of ammonia we abstract 

 water, we thereby obtain cyanogen, as shown in this table : 



