88 Journal of Agricultural Research voi. xviii, No. 2 



comparatively short period to any desired solution. A large number of 

 plants may be developed to a uniform stage, and we may then compare 

 different solutions from which absorption is taking place with plants of 

 equal leaf and root development. In brief, the plant is regarded merely 

 as a controlled absorbing system to be investigated. 



/0C 



60O ' 



SCO 



*O0 



xffa 



209 



-300 



-SOIC/T/OA/ I 



so^c/r/o//2zz 



^t'ya. 



Fig. I.— Water cultures, series i. Graph showing net absorption in parts per millioa from solutions of 



four concentrations: 



Solution I with concentration of o.io atmospheres. 



Solution II with concentration of 0.32 atmospheres. 



Solution III with concentration of 0,85 atmospheres. 



Solution IV with concentration of 2.07 atmospheres. 



Such a procedure was accordingly carried out in the next experiment. 

 Fifty-six uniform seedlings (2 in each i -liter bottle) were grown for 

 several weeks in a nutrient solution of 0.85 atmospheres concentration. 

 At the end of this period the bottles were divided into four groups. 

 After the roots were rinsed with distilled water the plants were trans- 



