528 
Journal of Agricultural Research 
Vol. VII, No. 12 
between colloidal and soluble iron. Calculations showed, however, that 
the concentration of available iron in many cases must have been less 
than one part in 10,000,000 of solution 
Reference was made to the bearing of these results on the proper com¬ 
position of plant nutrient solutions. 
LITERATURE CITED 
(1) Benecke, Wilhelm. 
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(2) Cameron, F. K., and Bell, J. M. 
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Dept. Agr. Bur. Soils Bui. 41, 58 p., 5 fig. 
(3) Crone, Gustave von der. 
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hfihere Pflanzeund eineneue Nahrlosung... 46 p. Bonn. Inaug. Diss. 
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m -• 
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(8) Hartwell, B. L., and Kellogg, J. W. 
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Exp. Sta. Ann. Rpt. 1904/05, p. 242-252, 
(9) Lachowicz, B. 
1892. Uber die Dissociation der Ferriphosphat durch Wasser und Salzldsungen. 
In Monatsh. Chem., Bd. 13, p. 357. 
(10) MazE, P., Ruot, and Lemoigne. 
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1 'absorption du fer des sols calcaires. In Compt. Rend. Acad. Sci. 
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(11) Morse, F. W., and Curry, B. E. 
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4 hg- 
(12) Ruprecht, R. W., and Morse, F. W. 
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(13) Schreiner, Oswald, and Reed, H. S. 
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(14) Stokes, H. N., and Cain, J. R. 
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ical reagents. In U. S. Dept. Com. Bur. Standards Bui., v. 3, no. 1, 
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(15) Takeuchi, T. 
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