Mapping Soils and Alkali. 39 



Table for determ in hig total mlt content of irafer from resistance at 60° F. 



When samples of water are examined in the field l)y the chem- 

 ical methods described on the preceding page, the following table 

 will assist in the calculation of parts per 100,000 of NaoCOg, 

 NaHCOg, and XaCl. Fifty cubic centimeters of water should be 



used in making the titrations. 



