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The beneficial effects of soil, bacteria have lately received much 

 emphasis. The Outlook notes popularly the recent investigation 

 of injurious soil bacteria — (October 29, 1910) at the experiment 

 station at Rothamsted, England. "It occurred to the experi- 

 menters at Rothamsted that perhaps there exist similarly in 

 the soil, not only the "good" microbes that can be reinforced 

 at will, but "bad" organisms that, as in the human system, are 

 at warfare with the benefactors. And this was demonstrated 

 to be a fact. Perhaps, then, they thought, we can not only 

 reinforce the helpful organisms by addition from without, but 

 treat the soil with something that will kill or minimize the effect 

 of those undesirable. Isolating the organisms and experimenting 

 with them, it was soon found that various antiseptics, in liquid 

 and in vapor form, will kill or paralyze the undesirable organisms, 

 and hence, if applied to soils, materially increase their yield, 

 even without a reinforcement of the army of their natural enemies, 

 the ammonia-forming bacteria; and at length it was discovered 

 that heat alone will answer every purpose. Partial sterilization 

 of the soil by heat, while destroying some of the desirable bacteria, 

 totally destroys those that prey upon them. Cans of earth from 

 the same field heated to about the temperature of boiling water 

 yield enormous growths of leaf and seed compared with identical 

 samples unheated. Here is the sign-post that points to a most 

 fascinating path of research. Perhaps some way will be found 

 ta apply this discovery practically. Experiment will not rest 

 here, although it seems at first thought impossible to heat the 

 soil over any large area; yet in greenhouses it might pay, where 

 the area under cultivation is relatively small and the crop rela- 

 tively very valuable. A lady of our acquaintance found it im- 

 possible to grow certain flowers in a pot; the seeds germinated, 

 but the plants failed to mature. Thinking that there might be 

 some worm or grub in the soil that attacked the seeds or the 

 roots, and that heat might kill it, and as fresh soil was not easy 

 to secure in the city, she put the pot in the oven and baked the 

 contents. Afterwards there was no trouble when the seeds were 

 again planted. She had unconsciously confirmed the Rotham- 

 sted experiment, destroying the harmful bacteria. Professor 



