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CHAPTER VIII 



HOW DOES ELECTRICITY AFFECT THE GROWTH OF 



PLANTS ? 



IT will be of interest to consider some of the theories which have 

 been deduced as to the actual effect of the electrical discharge upon 

 vegetation. 



Nitrogen. 



Electricity is believed to have a nitrifying effect upon the soil, 

 and every farmer knows the value of this ingredient in raising 

 crops. Analysis have been made of soil taken from under the 

 electric discharge wires in which more nitrogen was found than in 

 soil taken from the unelectrified area. Nitrogen composes about 

 four fifths of the atmosphere, but in its free state is not made use 

 of by plants as food, except in the case of leguminous plants whose 

 power of obtaining nitrogen from the air is connected with the 

 formation of nodules, the bacteria of which penetrates the roots 

 and fixes the nitrogen, thus storing it up in the plants for them 

 to feed upon. To show the importance of electricity in connection 

 with the nitrification of the soil, rain brings down about 10.7 

 pounds of nitrogen per acre a year, and a greater proportion is 

 precipitated by thunder rain than by rain when the atmosphere is 

 less electrically charged the lightning discharge causes a com- 

 bination of the oxygen and nitrogen in the air, the product of 

 which is brought down by the rain to earth, thereby adding small 

 quantities of nitrates to its store for the nourishment of plants 

 and which, though by no means sufficient to maintain the supply 

 required by them, is & considerable supplement to artificial 

 methods of enriching the soil if, therefore, we can increase this 

 supply of nitrogen to the soil from natural and manurial sources 

 by aid of the application of electricity, that in itself would be a 

 considerable gain. 



Assimilation. 



Another suggestion is that the electric current in the earth 

 assists in making certain plant foods contained in it more soluble, 

 and therefore more easy of assimilation. To take an everyday 

 analogy we irr'ght compare the action of the current to one of 

 "" peptonising. " The sun has a powerful action on the soil in 



