8 THE SPIRIT OF THE SOIL 



There seems no reason to believe that there can 

 ever be a lessened demand for nitrates. With the 

 continued increase both of population and of 

 standard of comfort, and with the rapid exhaustion 

 of the virgin soils that were to be met with in the 

 early days of farming in America and Canada, the 

 drain made on the world's stock of nitrates by agri- 

 culture must continue to increase; the present war 

 indicates that the demand made by explosives for 

 munitions of war will be more than maintained, while 

 great engineering works will probably absorb more 

 than in the past. Lastly, with the increased activity 

 of the chemical trade it seems inevitable that in this 

 direction, too, a further increase in the production of 

 the world's nitrates will be essential. 



From the standpoint of supply the situation at 

 first sight does not seem promising. As Sir William 

 Crookes pointed out, the exhaustion of the natural 

 deposits is already in sight, and there seems no valid 

 reason for believing that new sources of nitrates will 

 be discovered to replace the old. Chemical pro- 

 ducers of nitrates will before long find themselves in 

 serious competition with other users of power. With 

 the introduction of the motor car farmyard manure 

 will become less and less available, while at present it 

 has seldom proved practicable to utilize the waste 

 sewage produced in the great towns. As one writer 

 has expressed it, it is no more reasonable to quarrel 

 with the farmer for not utilizing the sewage of the 

 towns than it is to quarrel with the manufacturers 

 for not collecting and burning the vast masses 

 of carbon that are poured out daily from the 



