104 



THE LIFE OF THE PLANT 



stores of nitric acid, which under other circumstances 

 were washed away by the rain and therefore lost 

 to the farmer. Such a utilisation of the nitric acid in 



the soil would 

 to a certain 

 degree explain 

 why it is that 

 crops of legu- 

 minous plants 

 produce more 

 nitrogen than 

 other plants ; 

 and, moreover, 

 leave an excess 

 of the nitrogen 

 in a form in 

 which it can- 

 not be washed 

 away by the 

 rain, namely, 

 in the remains 

 of their roots, 

 for the benefit 

 of the succeed- 

 ing plants. 



Neverthe- 

 less, this ex- 

 planation was 

 unsatisfactory, 

 and the ques- 

 tion remained 

 unanswered 

 FIG. 29. until it sud- 



denly received 



an explanation about the end of the eighties. This 

 discovery is one of the most brilliant contributions of 

 recent years to the theory of the nutrition of the 



