A WORD ABOUT MANURES. 293 



sues are composed of these identical elements of the soil. 

 Truly and literally, we are made of dust. But the animal 

 kingdom does not derive its sustenance directly from thje 

 soil — that would be impossible. Our digestive organs are not 

 constructed for that purpose, and could not assimilate such 

 food, though in the great famine of Germany, in the 18th 

 century, the starving millions did essay it only to die in 

 torture. Nature has provided an intermediate agent, vege- 

 tation, whose organs are nicely adapted to this purpose. 

 They send down into the soil their sensitive feelers, and pick 

 up such stray bits of food as men or beasts require. They 

 store it away in their granaries until it is called for, and 

 these kind friends, are thus the purveyors to animal life. 

 Not only is man thus directly fed by these natural agents, 

 but, to keep up a constant unceasing supply, a large propor- 

 tion is sent back to the soil, in a form to. invigorate man's 

 food. This refunded capital is variously called humin, 

 ulmin, geine. Ulmin or ulmic acid, is the first formed ; hu- 

 min is formed from ulmin by the absorption of oxygen; 

 geine or geic acid from humin by the further absorption of 

 oxygen. 



We will describe all these changes, however, under the gen- 

 general term of geine. Under some form geine is essential to 

 agriculture. It is the result of decaying vegetable matter, or 

 in other words, it is the active principle of mould, and is the 

 direct result of putrefaction. It is carbon, oxygen and hy- 

 drogen. It has a powerful affinity for nitrogen, one of the 

 constituents of the atmosphere, and whenever it comes in 

 contact, the hydrogen of the geine unites with the nitrogen 

 of the air, and ammonia is the result. It also absorbs water 

 freely, and this is why bottom lands, full of geine, fail to 

 suffer from drought. The geine attracts moisture from the 

 air and keeps the plant alive. These salts, humin, ulmin 

 and geine, were formerly called extract of mould. They 

 are, for the most part, soluble in water. For the sake of 

 brevity, we will embrace all these salts as well as erenic and 



