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THE ROYAL SOCIETY OF CANADA 



Where H = capillaiy lift in cms. 



T =surfacc tension of watei- in dynes per linear centimeter = 

 75 dynes. 



D = effective diameter of soil pore. 



S = specific gravit}' of water = 1, 



g = 980 dynes. 

 In making these calcnlations we assumed that the soil grains have 

 the attraction of glass for w^ater, and that the ti-iangular pores of the 

 soil are capable of lifting water to the same height as circular pores of 

 eciuivalent cross section. 



TABLE 4. 



Giving a comparison of the calculated and observed capillare lifts of the soil 



constituents. 



Conclusions. — (1) The finer the grains of a soil constituent, the 

 greater is the capillary lift of the constituent. (2) The observed 

 capillary lift falls between the calculated limits in every case except 

 that of clay. 



The case of clay is considered in Part III. 



Part HI. 



The 'pressure of the atmosphere limits the capillary lift which can be 

 obtained by this method. 



When we began these experiments we believed that we might be 

 able to observe a capillary lift of over 10 meters or 34 feet; that is, 

 a greater lift than the length of water column supported by a pressure 

 of one atmosphere. This we have l)een unable to do. 



We have made many ex]>eriments with soils, the calculated lifts 

 of which are greater than 10 meters, but the greatest lift we have 

 observed is 30.1 feet. In the woik described in Part II the observed 



