G. W. Robinson and W. E. Lloyd 



147 



The mean values and probable errors calculated from these figures 

 are as follows : 



Similar determinations were not made for moisture and organic 

 matter. The determinations are made with much less trouble than the 

 mechanical analyses and P2O5 estimations, and therefore the moisture 

 and organic matter were determined four times on each boring and 

 averaged. The agreement was so close in all cases that p^ for these 

 determinations would be exceedingly small both absolutely and in 

 comparison with the corresponding values of P determined. 



