CLASSIFICATION OF ORGANIC SUBSTANCES. 311 



ical reaction of this nature is practically carried out, and 

 to enable you to understand that the " substitution " is not 

 merely a new arrangement of letters on paper, but an act- 

 ual rearrangement of the atoms of tangible matter. 



Now as a matter of fact, when the above operation is 

 carried out the liquid which distills over, on heating with 

 potassium hydrate, contains other bodies besides ethyl- 

 amine. For not only is one atom of H replaced by C 2 H 5 , 

 but two, and all three atoms are likewise replaced, yielding 

 bodies having the composition shown in the formulaB fol- 

 lowing : 



(H (H (C 3 H 5 



N < H N < C a H 5 N -j C 2 H 5 



(C 2 U 5 (C 2 H 5 (C 3 H 5 



Ethylamine. Diethylamine. Triethylamine. 



These bodies are chemical curiosities; but we have explain- 

 ed their formation and constitution in order that you may 

 have some idea of the group of Amines, for to this class of 

 bodies it is believed that the Alkaloids belong; and the al- 

 kaloids you will learn are of immense importance, includ- 

 ing as they do the valuable and interesting bodies quinine, 

 strychnine, morphine, etc., occurring in plants. When the 

 replacing radical contains oxygen, the new body formed is 

 called an amide, but these are of less importance. 



426. Organo-metallic Compounds. These are compounds 

 of hydrocarbon radicals with monad, dyad, and tetrad met- 

 als, but, being mere chemical rarities for the most part, do not 

 interest us. One of them, called zinc-ethyl Zn(C 2 H 5 ) 2 

 is a volatile liquid with a disagreeable odor, and possesses 

 the property of igniting spontaneously in contact with the 

 air, like phosphoretted hydrogen. "We will not return to 

 this class of bodies. 



427. Organic Analysis. Analytical chemistry does not 

 come within the scope of this work, but we will tell you 



