FIXATION OF NITROGEN 53 



it on a pure culture medium, and named it Bacillus 

 radicicola. 



Two years later, in 1890, Prazmowski succeeded 

 in inoculating the roots of bean plants growing in 

 sterilized soils, and in obtaining luxurious growth by 

 simply watering the plants with a liquid culture of 

 the organism. 



It was when this stage had been reached that the 

 direct commercial application of the knowledge 

 newly obtained first fired the imagination as a means 

 of enormously increasing the earth's fertility. The 

 enthusiasm was thoroughly justified, for those 

 familiar with the amazing efficiency of bacterial 

 action, and familiar, too, with the results obtained 

 when the conditions of growth could be satisfactorily 

 controlled, as in the hothouse, were confident that 

 only a little more experience was necessary for 

 similar results to be obtained in the field. 



Professor Nobbe of Germany was the first to try 

 and capture the market. His method was to collect 

 the bacteria from various leguminous nodules, plant 

 them in bottles containing nutrient gelatine, and 

 sell them under the trade name of Nitragin. Some 

 of the results Nobbe obtained were satisfactory, but 

 the percentage of failures was so great that the 

 method was to a large extent discredited, just as the 

 imperfections of method employed with Koch's 

 tuberculin in the early stages resulted in the dis- 

 crediting of a principle thoroughly sound. 



Nobbe's work had one good result, however. The 

 successes obtained had been such that in 1901 the 

 United States Department of Agriculture com- 



