Hall, How does the Plant obtain its nntrimeJit? 



the solutions was found to vary in accordance with the 

 history and composition of the soils, and the growth in 

 the solutions is such as might be expected from their 

 composition. 



A second set of experiments was then started in which 

 the deficiencies in the solutions from the unmanured and 

 partially manured soils were repaired by the addition of 

 phosphoric acid and potash, with the results set out in 



Wheat. Barley. 



Total Preduce 

 Lt). 



ffeifiht of plant 

 2.0 



Plot 



11 



1-0 2A 3A 



7-2 



Text-fig. I. Comparative yield of the crops in the field 

 (solid lines) and of the plants in the solutions from the same 

 soils (dotted lines). 



Table IV. As wheat and barley had given identical 

 results in the first trials, the later experiments were 

 confined to barley. 



From these figures it will be seen that the artificial 

 culture solution, which was calculated to be approxi- 

 mately equivalent to the soil solutions yielded by the 

 completely manured plots 4A and 7/2, yielded plants 

 whose weight (0763) was distinctly lower but of the 

 same order as those grown in the soil solutions 



