Nitrogen is no more important in the chain "than the 

 weakest link thereof," and yet it is so rare an article, the com- 

 mercial sources of it being so few, that he who will discover a cheap 

 commercial process for obtaining it from the atmosphere and 

 combining it in a form that will be sendceable in crop produc- 

 tion, not only will be a great benefactor and inventor, but will 

 change the economy of living on this earth. 



Phosphoric Acid, the Second Element 



,y^jj^^ Phosphoric Acid (P2O5) is the characteristic element of bone. 



Is Its office in plant feeding is primarily to furnish phosphorus to 



P2O5 plants, especially to their grains and seeds. No gr^in or 



seed could be formed without it, although it is found in the 

 stalks and leaves. As we know, the skeleton, or framework, 

 of men and of animals is bone, in which there is 13 per cent 

 of phosphorus. As grains and seeds constitute in some cases the 

 chief food of animals and of men, nature has provided that phos- 

 phorus shall be one of their important constituents. In other words, 

 as we trace back the structure of animals to plants, and of plants 

 to plant food ingredients, we find those ingredients to predominate 

 in virgin soils which are necessary for, and which predomi- 

 nate in, the structure of animals or men. 

 ^jj^^ In addition to supplying phosphorus, soluble and available 



It phosphoric acid seems to have a stimulating influence on the 



Does feeding capacity of plants and on the soil. It seems to be a 



"mixer" and a promoter of plant assimilation and digestion. On 

 that account it hastens maturity in many cases. For example, 

 soluble phosphate of lime is almost a specific for certain root 

 crops like turnips and beets, and yet phosphorus does not enter 

 largely into the composition of these crops. Besides supplying 

 phosphorus to the kernel of com, soluble phosphates of lime are 

 absolutely essential in the hastening of the maturity of the com 

 crop. Phosphoric acid in the form of phosphate of lime also con- 

 stitutes a splendid base upon which to bmld a complete fertilizer. 

 In the form of acid phosphate (phosphates of lime dissolved in 

 sulphuric acid), it constitutes in many cases the "bulk" of 

 commercial fertilizers, which is referred to elsewhere. 



We do not find phosphorus or phosphoric acid in an uncom- 

 bined form in nature, but always united with some base or 

 alkali, chiefly with lime in the form of phosphate of lime. 



8 



