156 



RECLAIMING ALKALI LANDS 



pea ted. Thus, there may be a constant stream from the 

 subsoil to the surface, particularly if the water-table is 



FIG. 19. TYPICAL HARD PAN FOUND IN ARID SOILS. 



within two or three feet of the surface. All the water 

 that moves transports some salt, and since none of the 

 salt can be evaporated, all of it remains as a surface ac- 



