47 



The rearults of nitrogen determinations in drainage 

 water (Bu. Soils 26 j Rothamstead Tv'emoirB, V. 91) from 

 plats of wheat variously fertiliaftd ar© int«:*rfecting in this 

 connection. This land responds abundantly to nitrogenous 

 fertiliz-^r. fh» NO^ ae nitric acid found in ths drainage 

 water and the yields a?'t. shown in Table XiX. 



Table XIX : NOg as Nitric Acid in Drainage Water, 



and Yield of Wheat at The Rothanstead Station. 



The Amount HOg p. p.m. Arranged in Ascending Orde-r, 



NO3 Yield • 



rheat 

 p. p. ill, lb8. 



3.9 1726 



5.1 1988 



8.5 3348 



13,9 3f387 



14.0 5013 



15.1 4480 



15.3 3716 



16.1 5304 



17.4 4967 

 18. 4 ^920 



19.2 4716 



The increase in yield is correliated with the increase 

 of NO3 in the drainage water till 15.1 p. p. a. IO3 is reached. 



