239 



great increase in the manufacture of superphosphate of lime, 

 and the consequent speedy exhaustion of the bone supply, 

 soon rendered the working of the mineral phosphates 

 necessary. 



Although at present the world's production of ground bone 

 amounts to about 75,000 tons, no appreciable amount is con- 

 verted into superphosphate, as the latter is now almost 

 exclusively prepared from mineral phosphates. America, 

 with her immense mineral resources, led the way ; she mined 

 1,278,330 tons in 1898 and 1,767,310 tons in 1899. Of this 

 latter amount 900,000 tons, valued at £15,000,000, were 

 exported, no less than 218,000 tons going to Germany for 

 conversion into superphosphate of lime. 



For a long time German agriculture was content to follow 

 in the wake of the United Kingdom ; but, during the past 

 thirty years, a large number of chemists at the various 

 agricultural academies have been engaged upon the scientific 

 and technical extension of the theories promulgated by Liebig. 

 One of the tangible results of their studies is the application 

 of the ground slag of the Thomas- Gilchrist steel process to 

 manuring purposes. Of this slag the production amounted 

 in 1899 to about 900,000 tons, of which about 100,000 tons 

 were exported. This industry is of recent date, the output 

 in 1886 having been only 25,000 tons. 



In this connection it may be noticed that H.M. Consul- 

 General at Berlin thinks that there might be a demand for 

 basic slag of English manufacture in Germany* 



Germany's annual requirements of artificial manures have 

 been estimated as follows : — Superphosphate, 500,000 tons ; 

 slag phosphates, 400,000 tons ; ground bone and guano, 

 70,000 tons ; precipitated phosphates, 5,000 tons ; Chili salt- 

 petre, 350,000 tons; sulphate of ammonia, 90,000 tons; 

 potassium salts, 600,000 tons ; or a total of a little over two 

 million tons. 



* Foreign Office Reports, Annual Series, No. 26ji. 



