4G2 MB. J. B. LA.WBS, DB GHLBBBT, AMD DB PUOB OB 



of atmospheric ammonia had been b certained, the mflnenra of that ource may, in the 

 case of these new results, be entirely overlooked. 



The fact that a given amount of Nitrogen in the form of com bi nation of a nio 

 more efficacious tli in i the Bame amount supplied in either of the anunrmiaca l salts exp - 

 rimehted upon, was held to Bhow that the nitrate was taken up by the plants a^ such, 

 and w;is not previously transformed into ammonia. 



M.Villb's experiments, as a whole, thus indicated that plants can take up Nitrogen 

 in three forms — namely, as nitric acid, as ammonia, and as free Nitrogen. He enume- 

 rates the following ((inclusions: — 



1. By means of nitre we may prove, without the aid of an enclosing apparatus, that 

 plants absorb and assimilate the gaseous Nitrogen of the atmosphere. 



2. Nitre acts by its Nitrogen. It is absorbed in the state of nitre. 



3. In relation to the amount of Nitrogen, nitre is more active than ammonia-sal t& 



9. M. G. Ville's collateral experiments to control or explain his results*. 

 M.Ville adduces evidence of yet another kind, in support of his new that plants 

 assimilate the free Nitrogen of the air. Air was passed through an otherwise clo^ d 

 apparatus, in which was placed a vessel containing calcined sand, or calcined sand 

 and decomposing organic matter. In no case was nitric acid formed. Nitrification, the 

 result of the combination of the oxygen and nitrogen of the air within the porous soil, 

 was not, therefore, the source of the Nitrogen gained by his experimental plants. 



Experiments were made in which a given amount of organic matter (Lupins, Gelatine, 

 &c.) was mixed with calcined sand, and exposed in an apparatus to a current of air, 

 which carried the gaseous products into acid, to retain 'any ammonia that might be 

 formed. The determination of the Nitrogen remaining in the matrix, and of the ammonia 

 given off and absorbed by the acid, showed a loss of Nitrogen, which could only have 

 passed away in the free gaseous form. 



Other vessels of sand were prepared, to which similar known amoimts of organic 

 matter were added, and then seeds of Wheat were sown, the organic matter serving as 

 manure. When the growth was stopped at a certain stage, almost exactly the same 

 amount of Nitrogen was found in the Wheat plants and in the sand, &c, as was origin- 

 ally contained in the seeds sown and in the organic matter added. Assuming that the 

 decomposition of the organic matter had taken the same course as in the other experi- 

 ments — free Nitrogen being given off — it was obvious that a corresponding amount of 

 free Nitrogen had been taken up by the plants. In other cases the growth of the 

 Wheat was allowed to continue longer than in the experiments just alluded to ; and 

 then the total Nitrogen in the products not only equalled, but considerably exceeded, 

 that in the seed sown and in the organic manure. In this instance, at least, it could 

 not be said that the Nitrogen not received by the plant as ammonia had been taken up 

 by it as nascent Nitrogen evolved in the decomposition. 



* Kecherches Espe'rirueutales sur la Vegetation, 1S57. 



