104 



THE LIFE OF THE PLANT 



stores of nitric acid, which under other circumstances 

 were washed awa}- by the rain and therefore lost 

 to the farmer. Such a utihsation 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, namelj', 

 in the remains 

 of their roots, 

 for the benefit 

 of the succeed- 

 ing plants. 



Neverthe- 

 less, this ex- 

 planation was 

 unsatisfactor}', 

 and the ques- 

 tion remained 

 u n answered 

 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 





Fig. 



