The First Land Plants 



One form of culture of these germs, u nitragin," 

 was actually made and sold on a commercial scale. 

 This was prepared after the suggestions of Nobbe and 

 Hiltner. It is no longer manufactured in bulk, though 

 even in 1903 the last named declared that of 98 inocula- 

 tions, 83 per cent, were successful, and only 9 per cent. 

 failed. 6 On gravelly sand, on clay and on peat, Dawson 

 found that nitragin was of some service, but it was worse 

 than useless on garden soil and on sand. 7 



The American " nitroculture " distributed by Moore 

 is said to have in one case doubled the harvest of 

 vetches. When cut green the inoculated crop amounted 

 to 23 tons per acre, and that not inoculated to 1 1 tons 



7 cwt. per acre. But there seem to have been many 

 failures. 



Professor Bottomley in 1906 and 1907 produced 

 " nitrobacteria," which also is a living culture of these 

 germs. His efforts were very energetically assisted by 

 the newspaper press, which in scientific inventions of 

 British origin is most encouraging. 



According to his own statement, he obtained himself 

 yields of 50 per cent, more nitrogen from inoculated 

 plants. In field experiments 12 tons 5 cwt. of fodder 

 (tares) were got per acre from nitrobacterine and 9 Ions 



8 cwts. per acre from nitrate of soda. 8 



One could hardly imagine a better place for such 

 inventions to be tested than the Royal Horticultural 

 Society Gardens at Wisley and a very elaborate series 

 of experiments were carried out there in 1908. The 

 results were that the total weight of the crop from seed 

 which had not been inoculated was heavier by 14 per 

 cent, than that got from the nitrobacterine seeds. 



In some soils the decrease due to inoculation was 

 far more than this (even 27 per cent, in the weight of 

 peas), and though there were instances of an increase in 



47 



