CAPILLARY MOVEMENT OF SOIL MOISTURE. 

 Table 36.— Flume 43. 



49 







Log i 



Log y 



1.224 







days. 



y 



inches. 



(log 

 days). 



(log 

 inches). 



+ .186 

 logz. 



(inches). 



A 



1 



1'5. 70 







1.196 



1.224 



16.75 



+1.05 



2 



18.95 



.301 



1.278 



1.280 



19.05 



+0.10 



3 



20. 75 



.477 



1.317 



1.313 



20.56 



-0.19 



4 



22.00 



.602 



1.342 



1.336 



21.68 



-0.32 



5 



22.82 



.699 



1.358 



1.354 



22. 59 



-0.23 



6 



23.75 



.778 



1.376 



1.369 



23.39 



-0.36 



7 



24.45 



.845 



1.388 



1.381 



24.04 



-0.41 



9 



25. 25 



.954 



1.402 



1.402 



25. 24 



-0.01 



It 



25. 75 



1.000 



1.411 



1.410 



25.70 



-0.05 



11 



26.25 



1.041 



1.419 



1.419 



26.25 



0.00 



12 



26.75 



1.079 



1.427 



1.425 



26.61 



-0.14 



13 



27. 15 



1.114 



1.434 



1.431 



26.98 



-0.17 



15 



27.75 



1.176 



1.443 



1.443 



27.75 



0.00 



17 



28.37 



1.230 



1.453 



1.453 



28.37 



0.00 



28 



31.00 



1.447 



1.491 



1.493 



31.12 



+0.12 



39 



33.00 



1.591 



1.519 



1.520 



33.11 



+0.11 



48 



34.00 



1.681 



1.531 



1.536 



34.36 



+0.36 



50 



34.75 



1.699 



1.541 



1.540 



34.68 



-0.07 



* 2/e. distance in inches computed by using the formula derived for flume 43. 



The 18 sets of observations are divided into two groups of 9 each. 

 The sum of the first 9 log x and log y are found, together with the 

 second group of 9. These are indicated as 29 in the computations. 

 Since the formula log y= log a -f- n log x applies to all parts of the 

 curve, it is the same for the two groups, subtracting the two groups 

 from each other eliminates log a and dividing the one difference A by 

 the other gives the exponent n, 



log V2 — log y 1 



^2, — 



lOg X.y lOg X x 



The sum of all the values of log x, S 18 , is found and multiplied by 

 n, and the product subtracted from the sum of all the log y, log a = 

 log y—n log x. The difference, A, is divided by 18 and the quotient 

 is the log a. 



The actual computations for the above case are as follows : 



log 



x^ = 



5.657 





y . 



12.060 





6.403 





n = 



1.191 _ 

 6.403 



log 



x S 18 = 



17.716 



7.716 x 



0.186 = 

 A = 





22.032 



-5-18 = 



1.224 = 





a = 



16.75 





y — 



16.750 °- 1 



7°— 20— ] 



3ull. 835- 



1 



l0£ 



0.186 



lot 



y S = 12.068 

 2 9 = 13.259 



A=r 1.191 



25.327 

 3.295 



22.032 



log a 



