THE OEIGIN OF SOILS 



45 



The succession of the strata in the tertiary and secondary 

 formations is also illustrated in a diagrammatic fashion in 

 the section (Fig. 4). The average thickness of the beds, 

 as they occur in this country, is approximately indicated 

 by the scale of the drawing and the nature of the materials 

 of which they are composed by the shading. 



The characteristic properties of soils correspond more 



