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artificially present the seeds with power to develop tubercles of 

 themselves he could make legumes grow in the most hopeless soil. 



After much labour he isolated the nitrogen-fixing bacteria. He 

 succeeded in breeding and colonizing the germs, and then pro- 

 ceeded to put them on the market. He advertised them widely as 

 able to make legumes grow in the poorest soil. Naturally the 

 announcement made a great sensation, and farmers from all 

 quarters of the globe wrote him for sample bacteria. He sold 

 different preparations for different crops, putting them up in bottles 

 and calling them Nitragin. But the bacteria did not work the 

 miracles promised. Seeds inoculated with them failed to develop 

 tubercles. A few persons, to be sure, obtained wonderful results, 

 but the vast majority of cases were complete failures. The bacteria 

 burned themselves out and disappeared without producing a single 

 nodule on the plants. They lacked permanence. The Nitragin 

 was withdrawn from the market. 



These two men had done a great service to mankind ; one had 

 solved the problem of why certain plants enriched instead of drained 

 the soil— he had isolated the microscopic agents, the myriads 

 of organisms which would carry back to mother earth what others 

 had stolen ; the other had shown that man could breed as many 

 of these little helpers as he desired, but he had not been able to 

 give them permanence, so that men could get service from them. 



At this point the inventive genius of an American, Dr. George 

 T. Moore, came to the rescue, and saved the discovery by giving 

 it just the practical value it had lacked. Dr. Moore is in charge 

 of the Laboratory of Plant Physiology of the Department of 

 Agriculture, and a widely known practical botanist. He had been 

 watching Dr. Nobbe's experiments and had come to the conclusion 

 that Dr. Nobbe did not cultivate his nitrogen-fixing bacteria in the 

 right way. The German's method of rearing his germ colonies 

 resembled that of a rich father who gives his son everything he 

 asks for without making him work for anything. As a result, 

 when the youth is thrown on his own resources, he proves unable 

 to earn his own living, and collapses. Similarly, Dr. Nobbe, 

 instead of developing the natural inclination and ability of his 

 bacteria to hunt out nitrogen for themselves, dulled and destroyed 

 this ability by giving them large quantities of nitrogen food, in 

 what we might call predigested form ; he so satiated them with 

 nitrogen that they lost their ability to hunt for it themselves, and 

 when turned out of the laboratory, were helpless. They soon 

 consumed the store of nitrogen which they had received, but 

 could not by themselves get any more. The nitrogen-fixing 

 ability was gone and they perished. 



Dr. Moore decided not to dull the appetite of the nitrogen-fixing 

 bacteria by giving them all the nitrogen they wanted ; bethought 

 he would whet their appetite, he would strengthen their nitrogen- 

 fixing power, by exercise, by giving them in their food just enough 

 nitrogen to make them want more and to make them strive to get 



