556 



Journal of Agricultural Research 



Vol. X, No. II 



and XVIII, and figures 8, 9, and 10. The titration of the control, in 

 which no sodium salt was present, was subtracted from each of the 

 others. 



/sa 



-3- /O /S- 20 



Fig. 10. — Graph showing the same system as in figure 7, but titrated with carbon-dioxid solution. 



Table XVI. — Titrations with carbon-dioxid solutions of the sodium nitrate-calcium 



carbonate solutions 



