[lynde-dupré] 



CAPILIARY LIFT OF SOILS 



123 



Method. — The apparatus was set up in duplicate for each soil 

 consituent in the manner described above, with the following exceptions. 

 With medium sand, which has a low capillary lift, we did not use a 

 capillary tube, we simply stood the funnels in the cups of mercury. 

 With fine sand and very fine sand we used short capillary tubes. 



Results. 

 TABLE 3. 

 Giving the capillary lift produced by the soil constituents. 



Comparison of the calculated and observed values of the capillary lifts 

 of the soil constituents. 



To calculate the effective diameter of the capillary pores of the 

 soil, we used the following formula derived by King.* 



13 



= I .2623 d^ 



Where D = effective diameter of soil pore, 

 d = diameter of soil grain. 

 We then calculated the limits between which the capillary lift of 

 each soil constituent should fall. We used the formula: — 



H 



4T 



D S 



^King, F. H., "Physics of Agriculture," p. 164. 



