FROM THE AIR BY THE LEGUMINOS^ I3 



this theory of Ville's was not accepted. Students were 

 taught that plants absorbed nitrogen from the air, but the 

 theory propounded by Ville to account for this assimilative 

 property was not admitted. Later on, Ville's experiments 

 were confirmed by Mene and Roy. 



These contradictions induced other scientists to attempt 

 to solve the problem afresh, and in the Rothamstead 

 Laboratory Messrs. Lawes, Gilbert and Pugh renewed 

 experiments, to reach a final conclusion agreeing with that 

 of Boussingault. 



These English scientists, however, seem very cautious in 

 the conclusion of their report, when they say that in carrying 

 out numerous experiments on the Gramincce under widely 

 differing conditions of growth, assimilation of free nitrogen 

 has never been detected. 



In the experiments on the Leguminosa^ they found 

 growth was less satisfactory and the limits of variation were 

 smaller, but the results recorded showed no assimilation of 

 free nitrogen. They thought it desirable that further experi- 

 ments should be carried out on these same plants under more 

 favourable conditions. 



A doubt thus seems to be present in the minds of the 

 English scientists, in spite of their being better prepared 

 than any others by twenty years of practical experiments of 

 the nitrogen demands of crops. 



In 1873 H. Deherain expressed the opinion that 

 atmospheric nitrogen might have the property of entering 

 into combination with certain ternary substances — cellulose, 

 glucose — and, hence, with organic substances in the soil in 

 course of decomposition. 



M. Th. Schloesing proved that the experiments which 

 allowed M. Deherain to form this opinion were of no value 

 owing to the manifold grounds of error, and, wishing 

 to be thoroughly convinced, he repeated the majority of 

 these tests after eliminating these possible sources of error. 

 The gist of his conclusions was that neither by using sealed 



