Electricity — Radium-, N-, and X-rays 



on cross bars above the growing plants. These wires 

 were charged with electricity by means of a dynamo. 

 Others again have passed (electrostatic) currents through 

 the earth in which the plants were growing. Lemstrom, 

 who was successful with this method, supposed that the 

 soil bacteria were invigorated and wakened up by the 

 current, and that their activity helped the plants. 



On the other hand, a recent observer has declared 

 that continuous electric currents are distinctly injurious. 4 



For most of these details, we have to thank the late 

 Mr. Thwaite, whose interesting paper (Journal of the Royal 

 Horticultural Society, June 1908) contains full details of 

 his own apparatus for electrifying plants. 



The following table (also from results cited by him) 

 would seem to show that there is really some practical 

 benefit to be gained. 



Most of these experiments seem to have been carried 

 out with overhead wires. 



Priestley tried the Speschnew system of copper and 

 zinc plates with beans, and found that the average volume 

 of the bean increased from 1.5 ccm. to 2 ccm. (.0915 to 

 .122 cubic inch), whilst the average weight increased 

 from 1.7 1 gr. to 2.26 gr. (27 grains to 34.7 grains). 



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