26 



JHE ROYAL SOCIETY OF CANADA 

 Table 4. 



Comparing the Lime Requirement as determined by the Roth- 

 amstead method with the ratio of the resistances. 



Discussion. It will be noticed that if the ratio is -986 or under, 

 the soils are alkaline and the lower the ratio the greater the alkalinity. 

 Also if the ratio is 1-284 or above, the soils are acid and the greater 

 the ratio the greater the acidity. This suggests that if a sufficient 

 number of soils were tested a ratio might be found, in the neighbour- 

 hood of 1 • 10, such that if a soil gave a lower or higher ratio we should 

 know that it was alkaline or acid and to what extent. 



It was noticed during the course of these experiments that a 

 soil solution had the same electrical resistance when cloudy that it 

 had when cleared by centrifuging. This would indicate that the 

 electrical method might be used to find the lime requirement of soils 

 when the solutions were too cloudy to be titrated by the Rotham- 

 stead method. 



Conclusion. 



The results obtained in the experiments described above indicate 

 that it may be possible to workout an electrical method of determining 

 the lime requirement of soils. 



