72 Fertilizers 



Recent discoveries in western states. 



The development of the phosphate mines of South 

 Carolina, Florida and Tennessee was so rapid that grave 

 fears were entertained of complete exhaustion. The 

 future prosperity of the agriculture of the United States, 

 however, has been assured by recent discoveries of vast 

 phosphate fields in Idaho, Wyoming and Montana. 

 Estimates of the size of these deposits are much greater 

 than those of the eastern United States already developed 

 and the material is of a distinctly high-grade character. 



The conditions surrounding many of these deposits 

 are especially favorable for the manufacture of acid 

 phosphate. Copper smelters are situated not far dis- 

 tant which are capable of producing enormous quantities 

 of sulfuric acid as a by-product, which, as brought out 

 later, is used in large quantities in its manufacture. 



Basic-slag. 



Thomas phosphate powder, phosphate slag, odorless 

 phosphate, iron phosphate and basic-slag are some of 

 the names given to a waste product found in the manu- 

 facture of steel from phosphatic iron ores by a modification 

 of the Bessemer process in which an excess of calcium 

 oxide (lime) is used. It is a heavy, black powder weighing 

 more than any of the more common fertilizer materials, 

 and is extremely fine. 



The use of basic-slag is confined largely to the coun- 

 tries manufacturing steel from ores high in phosphorus. 

 It is produced in large quantities in England, France 

 and Germany, and in those countries is riot only one of 

 the cheapest sources of phosphoric acid, but is regarded 

 as a very valuable product. The composition varies 



