Manures and Commercial Fertilizers 111 



tilizers often put the nitrogen in their fertihzers on the 

 sacks as ammonia. This has become customary because 

 the figures look larger, for ammonia is a hydride of nitro- 

 gen and is only partly nitrogen, and nitrogen is the essen- 

 tial thing we are after. You can find the actual amount 

 of nitrogen in the article by multiplying the figures on the 

 sack for ammonia by 0.8235. Thus, if the sack brand 

 says that the mixture contains 3 per cent, of ammonia, 

 this means that it has 2.47 per cent, of nitrogen. In some 

 states the manufacturers of fertilizers print a great deal 

 on their sacks to make farmers think there is more in the 

 goods than there really is. For instance, the two follow- 

 ing analyses were recently submitted for our opinion: 



First 



Nitrogen 2 to 3 per cent. 



Ammonia 3 to 4 per cent. 



Soluble Phosphoric Acid 3 to 10 per cent. 



Insoluble Phosphoric Acid 7 to 8 per cent. 



Potash 7 to 8 per cent. 



Second 



Ammonia 2 to 3 per cent. 



Soluble Phosphoric Acid 6 to 8 per cent. 



Insoluble Phosphoric Acid. .2 to 4 per cent. 

 Equal to Bone Phosphate.. .4.36 to 8.73 per cent. 



Potash .2 to 3 per cent. 



Equal to Sulphate of Potash.3 .7 to 5 . 5 5 per cent. 



All this simply means, in the first article, that it proba- 

 bly contained 2 per cent, of nitrogen, 3 per cent, of soluble 

 phosphoric acid, 7 per cent, of insoluble phosphoric acid, 

 and 7 per cent, of potash, for when any sHding scale is 

 printed on the sacks it is always safe to assume that the 



