32 
The removal of the absorbed elements approached quite rapidly a 
constant in the case of the potash and ammonium salts, but more 
slowly in that of the phosphates. This was due to the excessive 
amounts of this constituent which had been added. By reference to 
tables on pages 5 and 8 it will be seen that when phosphates were 
added to the soil in light applications the concentration of the solution 
remained practically unchanged for an indefinite period. 
ACKNOWLEDGMENTS. 
Acknowledgments are due and thanks are hereby extended to Dr. 
W. P. Kelley for valuable suggestions and for interest shown through- 
out this investigation. 
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