400 



NATURE 



[December 9, 1915 



of two tons to the acre produced no beneficial 

 results. 



Pot plants treated with bacterised peat show, 

 as compared with controls, not only increased 

 g-rowth but sturdier habit and greater root- 

 development. This fact led to the sugg^estion that 

 the phenomena cannot be attributed solely to the 

 nitrogen-content of the fertiliser. It is, for ex- 

 ample, a well-known fact that the addition of 

 phosphorus-containing fertilisers brings about the 

 development of a more vigorous root-system than 

 is produced in soil poor in available phosphates. 



Following up the suggestion that the virtues 

 of bacterised peat are to be sought elsewhere 

 than in the nitrogen contained in the fertiliser. 

 Prof. Bottomley was led to the very interesting 

 conclusion that the growth of plants is conditioned 

 not only by the well-known substance-producing 



critical spirit that we confess that the evidence 

 does not appear to us strong enough to bear its 

 burden. Biologists need no reminder of the pit- 

 falls that beset their attempts to establish hypo- 

 theses by the method of comparison. Although 

 often the only method at our service, it is a very 

 clumsy one ; and in a subject of such importance as 

 the existence of a new type of food substances, the 

 evidence must be overwhelmingly strong before 

 the hypothesis which it supports may be accepted. 

 We do not think that Prof. Bottomley 's evidence 

 is strong enough to support this test. Never- 

 theless, it should not be dismissed lightly ; rather 

 is it a case like so many in biological science, in 

 which a just judge would order a fresh trial. We 

 understand that such a trial is to be conducted at 

 Rothamsted, and we hope, for the sake of horti- 

 culture and agriculture, that it may lead on one 



specimens of coleus gro*n at the Royal Gardens, Kew. The right-hand plant received humogen, while the left had 

 the usual pottine comoost. From " The Soirit of the Soil " 



potting compost. From " The Spirit of the Soil 



food materials, but also by hitherto unknown 

 growth stimulators. These substances, which he 

 claims to have isolated from peat, Prof. Bottomley 

 has called auximones. He believes that they play 

 a part in plant-nutrition somewhat similar to that 

 played by accessory food bodies in the nutrition 

 of animals. 



Like Prospero, who at first called up the wrong 

 kind of spirit, but succeeded on a second attempt, 

 Prof. Bottomley 's wand first evoked nitrogen, but 

 now waives that heavy apparition in favour of a 

 more delicate, Ariel-like auximone. Auximones 

 are "it," in the vulgar parlance of the day, or in 

 the more elegant language of Mr. Knox they are 

 the spirit of the soil. 



Prof. Bottomley brings forward evidence in 



favour of the existence of auximones and of 



the important part they play in activating the 



growth of plants. It is, however, in no hyper- 



NO. 2406, VOL. 96] 



hand to the demonstration of the fertilising value 

 of bacterised peat, and on the other to the just 

 judgment of the case for auximones. 



Frederick Keeble. 



DYSENTERY AND WAR. 



"n\YSENTERY is a term embracing several 

 »-^ varieties of intestinal flux. Anatomically 

 there is inflammation, and frequently ulceration 

 of the large bowel. Owing to improved sanitary 

 conditions the diseases described under dysen- 

 tery have become infrequent in this country, 

 though outbreaks occasionally occur, particu- 

 larly in overcrowded institutions. In the past, 

 however, widespread epidemics have prevailed, 

 notably one which raged between 1847 and 1856 ; 

 and in the tropics dysentery still deserves its 



