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1. 316. It was Beyerinck of Delft who first discovered that 

 the growth of the nodules was due to a real Bacterium and 

 he grew it in a nutrient medium outside the plant taking his 

 seed from a variety of leguminous plants. He gave the 

 Bacterium the name of Bacillus Radicicola. 



1.317. Hellriegel first discovered that the nodules en- 

 abled leguminous plants to make use of the free N. of the air . 

 by converting it into living organic albuminoid matter in 

 their bodies. Experiments made by Boussingault in France 

 and repeated by Lawes and Gilbert in England, confirmed 

 this point once for all. 



1.318. The manufacture of Nitragin was the result of 

 the experiments conducted by Professor Noble of Tharand 

 in growing pure cultures of Bacillus radicicola in gelatine to 

 which was added, when liquified, a decoction of the plant on 

 which the organism under investigation is accustomed to 

 feed. Noble found that the best results in the way of inocu- 

 lation were attained when the micro-organisms were got 

 from a soil growing plants of the same kind as those he 

 was experimenting with, so that in order to give vigour to a 

 clover crop, the soil should be inoculated with micro-organ- 

 isms obtained by cultivation from the nodules of the clover 

 plant, and so on. Thus the Bacillus radicicola of Beyerinck, 

 though it was recognised by Noble as the one original organ- 

 ism present in all soils, is powerfully affected in its nature by 

 the nature of the leguminous plant it grows on. Accord- 

 ingly in preparing material for inoculation, cultures made 

 from the nodules of the various species of leguminous 

 plants are kept distinct, so that they may be used for appli- 

 cation to crops of the same species only. 



1.319. The credit of cultivating Bacillus radicicola in a 

 pure state and of a kind best suited to each species of 

 leguminous plant, is due to Noble and Hiltner of Tharand 

 from whose hands the manufacture has now passed into the 

 hands of a Chemical Manufacturing Company who charge 



