236 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



menters used soil from fields which had already grown legumes with 

 which t;) inoculate newly reclaimed lands or lands upon which legumes 

 had not previously been grown. Salfeld as early as 1887 obtained good 

 results by this method on the Moor Culture Experiment Station, 

 Bremen, but it was only upon such lands that the inoculation produced 

 increased yields. On ordinary lands where rational methods of culture 

 had obtained the results were negative. This method of inoculation 

 is practised in America now when new lands are brought under the 

 culture of soy beans and of lucerne. But this method involves at 

 least two disadvantages, the great expense of transporting large quantities 

 of soil for a considerable distance and the imminent danger of dis- 

 tributing noxious pests and troublesome weeds at the same time. 



The first pure culture material used was " Nitragin," put upon the 

 market by the German firm of Hochst, but after extensive trials it was 

 abandoned as not giving the results expected of it. Its originators, Nobbe 

 and Hiltner, afterwards improved it, and it has since given good results 

 in several Continental experiments, even on land which had previously 

 grown leguminous crops. In this case the bacteria were grown and 

 distributed upon a solid gelatin nutrient medium. 



In 1904 Moore, of the American Department of Agriculture, developed 

 a method of growing the bacteria in liquid culture media poor in 

 nitrogen. Absorbent cotton wool was soaked in the culture thus 

 obtained, and dried at a low temperature. The bacteria adhered to the wool 

 and in this dried state they were distributed to farmers and gardeners for 

 use. He found that they would remain alive after drying in this manner 

 for a considerable time. Many satisfactory reports were received, but a 

 great number of failures were reported later from other sources, and in 

 this country the material rarely gave increased crops. Some of these 

 failures were attributed to the drying which the bacteria had to undergo. 

 The United States Department has now abandoned sending the cultures 

 out in this form and is distributing them in liquid devoid of nitrogen in 

 hermetically sealed bottles. 



In England Professor Bottomley, of King's College, London, has 

 prepared material very similar to that of Moore in America,* and with his 

 material, which he has called " Nitro-Bacterine," the following experi- 

 ment was carried out. 



The Experiment. 



I'ltut of the Experiment.-- The experiment was planned so as to 

 ascertain whether any benefit was to be derived from the inoculation of 

 leguminous crops under any conditions in such a naturally poor soil as 

 that of the Wisley Garden. One half of the ground set apart for the 

 I iperiment had for the past four years received ordinary garden cultiva- 

 tion, the crop in 1907 having been celery ; this part was divided from the 



* Professor liottomley, in Seed and Soil Inoculation for Legumes, writes (p. 8) : 

 "When n was decided to send out inoculating material ... it was necessary, in 

 \ ii m "I the N< w Yoik experiments, to find some other medium than cotton wool for 

 di tributioo oi the ]>ure cultures. Alter a number of experiments it was found 

 DO liblc to obtain a powder preparation of the bacteria." The culture material is 

 s< nt out in a sealed packet containing cotton wool quite similar to the earlier 

 American QUI tfaod, but in addition a number of dry earth-like particles. 



