EXPERIMENT STATION BULLETINS. 



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Fig. 6. — Titration curves — medium sand soil. , 



Curve No. 0. Initial titration curve, Ca(OH)2. 



No. 1. After standing one day, Ca(OH)2. 



No. 2. After standing two days, Ca(OH)2. 



No. 3. Back titration of Ca(0H)2 series with HCl. 



No. 4. Initial titration curve, HCl. 



" No. .5. After standing one day, HCl. 



No. G. Back titration of HCl series with Ca(OH)2. 



