46 



the depth of six times 9 inches, or in all 54 inches. The examination 

 of these samples of soil is as yet very incomplete, but the following 

 interesting facts have been ascertained : — 



Whilst the strong roots of the melilotus were found to penetrate 

 to the lowest depths of the sampling, there was very little develop- 

 ment of white clover roots beyond the surface soil. Whilst to the 

 eye, and to the hand, the subsoil where the melilokis had grown was 

 obviously pumped dry, and was somewhat disintegrated, to the full 

 depth sampled, that of the clover plot had no such characters. De- 

 terminations of moisture in the soils and subsoils show, at each of the 

 six depths, much less water in the melilotus than in the white clover 

 soils ; and the difference is by far the greater in the lower depths. 

 Calculated per acre, it would appear that, to the depth of 54 inches, 

 the melilotus soil had lost approximately 540 tons more water per 

 acre than the white clover soil ; and there can be no doubt that the 

 pumping action had extended deeper still. 



There is here, then, clear evidence that the plant, whose habit of 

 gi'owth, and especially whose range, and feeding capacity, of root, 

 suited it to the conditions, was enabled to take up much more water, 

 and doubtless with it much more food, than, under exactly similar 

 conditions of soil, were at the command of the plant of the much 

 weaker and more restricted development. 



Nitrogen as Nitric Acid in the Melilotus and White Clover Soils. 



That the deep-rooting melilotus did derive more nitrogen from the 

 subsoil than the shallow-rooting white clover is obvious from the 

 following facts : — Watery exhausts were made of each soil, at 

 each depth, and the nitrogen as nitric acid determined in them, by 

 Schlosing's method, as nitric oxide, by its reaction with ferrous salts. 



The f oUowir iable summarises the results : — 



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