12 THEORIES ON THE ABSORPTION OF NITROGEN 



Boussingault concluded from these results that plants 

 did not assimilate nitrogen gas from the atmosphere. 



This scientist brought his researches to a close by a sixth 

 experiment in which he supplied the plant with a nitrogenous 

 manure with the object of discovering whether such a manure 

 would facilitate the absorption of nitrogen by the plant. 



He realized that the presence of nitrogenous matter in 

 the soil did not favour the assimilation of nitrogen gas. 



We are thus in touch with those early researches which 

 were confirmed later by the scientists, Lawes, Gilbert, and 

 Pugh, of the Rothamstead Laboratory, and which allowed 

 M. Grandeau, whose scientific reputation is fully established, 

 to say, in 1879, in one of his lectures at the French School 

 of Forestry, that scientists were unanimous in denying to 

 plants, in any degree whatsoever, the faculty of assimilating 

 nitrogen gas. 



M. Georges Ville, still undeterred, began a series of 

 experiments in 1849, the results of which were first com- 

 municated to the Academy in 1852. 



Professor Ville started by showing that if in the experi- 

 ments of Boussingault, already cited, the plants absorbed 

 no nitrogen from the air, the reason was because a plant 

 is unable to develop normally in a limited atmosphere. 



These experiments were carried out in the " Jardin des 

 Plantes " in Paris, before a Commission from the Academie 

 composed of Dumas, Regnault, Payen, Decaisne, Peligot, 

 and Chevreul, and thev lasted two months, from August 

 4th to October 12th, 1854. ^^^^ actual methods employed, 

 which were subjected to a good deal of criticism, are of 

 no great account, but the gist of the matter was that at the 

 conclusion of its report the Commission expressed itself as 

 follows : — 



"The experiments which M. Ville has carried out at 

 the Natural Historv Museum confirm the conclusions he has 

 drawn from his earlier researches." 



However, until the publication of Hellriegel's researches 



