CAPILLARY- MOVEMENT OF SOIL MOISTURE, 



of such measurements. The vertical element is the distance meas- 

 ured from the surface of the water in the tank and the horizontal 

 element is the time in days. 



The re suiting- 

 curves for all these 

 soils have the para- 

 bolic form. Very 

 rapid movement of 

 the moistures occurs 

 for the first few 

 days, after which 

 the rate of move- 

 ment is more uni- 

 form , but it grad- 

 ually decreases with 

 the lapse of time. 

 It is observed from 

 the figure that the 

 rate of movement of 

 moisture in the heav- 

 ier soils, as typified 

 by the Whittier soil, 

 subsides much more 

 rapidly than does 

 the movement in the 

 sandier soils. 



The extent of 

 movement of mois- 

 ture in these soils is, 

 with the exception of 

 Idaho lava soil, in 

 inverse order to their 

 moisture equivalents. 

 That is, the Idaho 

 soil (sandy) with 

 the lowest moisture 

 equivalent showed 

 the greatest move- 

 ment of moisture, 

 while the Whittier 

 soil with the great- 

 est moisture equivalent showed the least movement of moisture. The 

 Idaho lava soil in the horizontal flume as in the vertical flume showed 

 a greater movement of moisture than the moisture equivalent would 

 indicate. 



120 

 110 

 100 

 90 



I 10 



V) 60 



CD 



JZ 



o 

 £ 50 



AO 



30 



20 













































| 













i 



1 



1 

 1 









































A 







































,o 













/ 









































i 











































































































Yt 

























































A 



































■\<A 



ii 



£ 









<? 











































>* 









































UT\\(\ V ^ 







































"^JL'/tkiiL 



^ \vi 







.\ 



































S>Wom^r h & 











V' 

































■ ; »X 









































h VRovr%< 











V 

































„ J .^ 







;' 

































^sV°. 





\- P 





/ 







































&/:&/ 









,0 



































*i 



^ 









1 r 



*s r 



/i- 





















•1 













i 











rs 













a nVV 



t 















J 











'- 





U^ 



1- 



e °j^f 















Cm 









,, 





/' 



n*»> 



5F 



'• „ 

















-* 



i 









t 





^e>M 



H ^^ 





















■;■-;, 









^ 

































«* 



' 1 





























W/ 



$ 



-s 







































y 







































f: 





t 









,-' 









































' 









, 



/ 













































•;/ 





Z! 



, 



/ 



























1 











































i 



























































































































































1 

































7 t 





















































hi* 























i 























i 



\f 





























i 

















¥ 



















I i 







i 



:l 





. 











t<? 



") 





















1 





r 



.^ft-r-T" 1 ' 



























wi 



i/ 



nL>-" 

































































































(-.or 



























Y '- 













. r 









i 





























M 













\° 





>" 

















































T 

























































' 













































f 









.-' 























































, 





























































































































































j 























































| 



















































































































































































10 



1 



















































































































































































































































































































































































































) IO 20 30 4-0 50 6 



Days 



o ! 



1 



Fig. 3. — Rate of movement of moisture in horizontal open, 

 flumes. Figures in circles indicate points at which that 

 number of liters of water had been taken up. The 

 dotted line for flume No. 71 (covered) is for comparison 

 with flume No. 70 (open). 



