70- 



60- 



2 40- 



S 



30- 



589 '.495 '.295 '.246 '.14 7 ' .12 4 ' .104 ' 

 Grode size in mr 

 HISTOGRAM 



40- 

 JO- 



20- 

 10- 



.495 .295 .246 .147 .124 .104 .088 .074 -.074 

 Grade Size m mm 

 SIMPLE FREQUENCY CURVE 



Grade size in mm 

 CUMULATIVE FREQUENCY CURVE 



Figure 80. Histogram, simple-frequency curve, 

 and cumulative-frequency curve, of the Da- 

 kota sandstone tabulated in table 6. 



