CHAPTER XIV. 



SUPERPHOSPHATES- UNCERTAINTY OF THEIR COMPOSITION 



THEIR MANUFACTURE DESCRIBED HOW TO MANIPULATE 



WHEN MADE -NATURE OF THE DECOMPOSITION PROCESS 



EXPLANATION OF THE LOSS IN WEIGHT WHAT IS 



SOLUBLE PHOSPHATE ? DISCUSSION OF ITS MERITS IN THE 



FIELD ITS ACTION IN THE SOIL NECESSITY FOR CARE- 

 FUL ANALYSIS MADE FURTHER MANIFEST PRECIPITATED 



PHOSPHATES THEIR MANUFACTURE THEIR VIRTUES 



AND SUPERIORITY USE OF COMPLETE MANURES WITH 



EXAMPLES AND STATISTICS REMARKS ON HOME-MADE 



CHEMICAL MANURES. 



The process of superphosphate manufacture, whether it be from 

 bones or mineral phosphates, is neither a very complicated nor dif- 

 ficult one, but it requires a certain amount of chemical knowledge 

 and experience which the majority of those concerned in it do not 

 possess ; and hence it is, that no article in the market is more varia- 

 ble, both in its physical condition and chemical composition. 



Nor can this remain a source of surprise, when we remember 

 that each manufacturer adopts some peculiar system of his own, 

 and that no two chemical factories bear any resemblance to each 

 other. 



Like every growing industry, it has been invaded by capitalists, 

 who have seen in it a possibility of realizing large interest on their 

 investment, and who, devoid of even elementary true knowledge, 

 have begun producing manures without the aid derived from prac- 

 tice and observation. 



