DRIFTING SAND. 



21 



Table XII. Mechanical Composition of Sand from a small Dune, 

 south of Moline, Ills. 



L.-ncth t.r 



diameter lu 



mm. 



49 



From ihe rear 

 slope ut the dune. 



Frrini thp top 

 of the dune. 



Fiom the top 

 of the dune. 



Lower front 

 elope o( tbeduDe. 



lG-8 



8-4 

 4-2 

 2—1 



1 



1 i 



J 1 



1 _ 



_ 1 

 1 (i 



_ 1 



64 



1 1 



tI^" 



1 



Table XII. (Continued.) 



Ton ot the 

 duoe. 



Upper front slope 

 of the dune. 



Top of the 

 duue. 



I.owPr front 

 ulupe ut theduue. 



Average, 



12.9 

 74.6 

 10.6 



.6 



\- 



