60 GEINE. 



other organic products, whose independent existence 

 has been determined ; for example, quinine, mor- 

 phine, 8tc. 



101. While the great mass of organic matter 

 of soil, is a well defined chemical compound, termed 

 geine, consisting of carbon, hydrogen, and oxygen, 

 there are traces of other general products of decay, 

 which, in addition to the four elements above, con- 

 tain nitrogen. There is thus naturally pointed out, 

 a division of the organic matter of soil, into two, 

 classes ; those which do not, and those which do, 

 contain nitrogen. 



102. The first class, or non-nitrogenous, comprises 

 three substances, which have been termed. 1st, ex- 

 tract of soil, or of humus ; 2d, geine, or humic acid ; 

 and 3d, carbonaceous soil, or humin. These are 

 chemically the same, passing from one state to the 

 other, without changing the relative proportions in 

 which they were combined. 



103. The second class, or nitrogenous, comprises 

 two substances — crenic and apocrenic acids. These 

 approach the three above named in their constitution, 

 and by some authors, they are considered identical. 

 The distinction of geine into nitrogenous, and non- 

 nitrogenous, is founded in nature. These classes 

 cannot mutually pass, the one to the other. The 



