48 



The Phosphates of America. 



The geological formation of what is commonly called its phos- 

 phate " belt " is made up of quaternary sands and clays. These 

 overlie the beds of Eocene marls, upon whose surface and inter- 



mixed with which is found the phosphate deposit. The presumed 

 total area covered by this characteristic formation, as shown by 

 the map, is 70 miles in length and 30 miles in width, extending 



