Feeding the Land 187 



or root, the preparation of the soil for plant-growth 

 is the same — to conserve plant-food in form of 

 moisture. There is a difference between water 

 and moisture. Most plants will live for a time 

 seemingly on pure water, but in truth only so 

 long as the supply or stock of food already in circu- 

 lation in them lasts; for pure water is not a complete 

 plant-food. Each plant needs a continuing supply 

 of the elements of which it is composed. Thus, 

 stating the case broadly, the chemistry of feeding 

 the plant for fruit means a supply of soluble potash, 

 but for leaf, stalk, or stem, a supply of soluble, or 

 available, nitrogen. The air about us is composed 

 chiefly of nitrogen, but so firmly fastened to the oxy- 

 gen and hydrogen as to be unavailable to the plant. 

 Doubtless the leaf, during its growing period, has 

 power or, so to say, is functioned to disassociate the 

 nitrogen from its companions. As yet we have 

 no cheap, abimdant, available nitrogen in form 

 of fertilizer, available as plant-food. Here is the 

 chemist's opportunity. Let us ask the men in the 

 great chemical laboratories, equipped by private 

 or by public means, at Berlin, at Washington, or at 

 the university, to discover, if they can, a form or 

 compound of nitrogen, abundant, cheap, easily 

 handled and applied to the land, and speedily solu- 

 ble in the soil as plant-food. This accomplished, 

 wheat and com and potatoes and beef and mutton 

 and the long list of human foods will drop in price. 

 Man will go up and food will come down. Here is 

 the opportunity of the industrial chemist. He may 



