12 FOOD FOR PLANTS 



bushels) each and shipped to all parts of the world. 

 The process of refining is an expensive one. 



How these beds of Nitrate were formed has been 

 the subject of much speculation. The generally 

 accepted theory is, that they were formed by the 

 gradual decomposition and natural manurial fer- 

 mentation of marine animal and vegetable matter, 

 which contains a considerable amount of Nitrogen. 



The same wise Providence that stored up the coal 

 in the mountains of Pennsylvania to furnish fuel for 

 people when their supply of wood had become ex- 

 hausted, preserved this vast quantity of Nitrate of 

 Soda in the rainless region of Chile, to be used to 

 furnish crops with the necessary Nitrate when the 

 natural supply in the soil had become deficient. 



The enormous explosive industry of this country 

 could not be conducted without Nitrate of Soda, and 

 glass works are dependent upon it. In fact, glass 

 works and powder works usually have Nitrate on 

 hand. 



Nitrate of Soda has a special bearing on the 

 process of modern agriculture, being the most nutri- 

 tious form of Nitrogenous or ammoniate plant food. 

 While the action of micro-organisms with certain 

 crops (legumes) combines and makes effective use 

 of the inert Nitrogen of the atmosphere, such action 

 is far too slow and uncertain for all the requirements 

 of modern agriculture, for it is not available for use 

 for a whole year or even longer. The rapid ex- 

 haustion of combined Nitrogen has several times 

 been noticed by eminent scientific men, with reference 

 to food famine, because of a lack of the needful Ni- 

 trogenous plant food. It has been estimated under the 



