28 University of California Publications in Agricultural Sciences [Vol. 1 



TABLE IV 



Effects of Mixed Alkali Salts 



The same marked losses in nitrates occur here as where the 

 salts are employed singly. NaCl seems to be responsible again 

 for the greatest losses, NboSO^ is next in order, and Na^COg 

 seems to have little or no effect. Since these salts occur together 

 in alkali soils, however, the results in Table IV possess consider- 

 able significance and interest, especially since they point out what 

 enormous losses of nitrates occur where such large amounts as 

 ten milligrams of each of the salts are added to the nitrate-con- 

 taining solution. 



The Interference of Precipitants of Clay and Organic 

 Matter on the Nitrate Determination 



It is very singular that analytical chemists have for so long 

 a time been employing such materials as saturated alum solu- 

 tions, aluminum cream, and bone black for precipitating clay 

 and organic matter in obtaining the soil solution to be used for 

 nitrate determinations without ever having attempted to ascer- 



