ELECTRICITY TO INCREASE CROP PRODUCTION. 
the discharge, were much less affected than the others. Professor 
Priestley, who examined them, stated that the ravages of the disease were 
largely inhibited by the electrical discharge, for during one week, when 
the influence machine broke down, the disease progressed more rapidly 
under the wires, and was again checked in re-starting the machine. 
A Crassiricatton or tHe Various Muruops. 
We might conveniently classify the various methods for applying 
electricity in crop production into five groups, as follows :— 
(1) Methods in which atmospheric electricity is collected and 
discharged to the crops. 
(2) Methods in which electricity is generated by some machine 
(Wimshurst dynamo), or from some commercial supply, 
and distributed to growing crops. 
(3) The electrification of the soil, or the plant or seed through 
the soil. 
(4) ‘Prolonged exposure to electric are light, or mercury vapour 
lamp (rich in ultra-violet light). 
(5) The electro-chemical treatment of the seed before sowing. 
User or Armospnertc ELEecTRICITY. 
Ti: the first method, the electricity is collected from the air ‘by a 
number of lightning conductors, either on special high towers built up 
for the purpose (e.g., Berthelot’s, at Meudon, in France), or on tall posts 
well insulated with very large insulators at the top. In middle and 
southern France, which is subject to hailstorms, lightning conductors of 
gilded electrolytic copper, raised 100 feet, often protect an area of about 
three-quarters of a mile all round each pole, and by conveying the 
electricity from the air to the ground, frequently disperse an impending 
storm. Many vineyards are thus saved, and the electricity is used in 
stimulating the growth of the plants so saved. 
The Basty method is to collect atmospheric electricity by means of 
‘iron rods (4-in. to d-in. diameter), ending in a non-rusting point, and 
driven into the ground 8 or 10 inches, according to the length of the 
roots of the plant to be treated. For vegetables, the rods should stand 
about 3 feet. high, and for wheat about 6 feet. Action is exerted over 
a radius of ground surface equal to the height of the rod. Some of 
Lieutenant Basty’s results in 1913 were so marked (potatoes, 73 per 
cent. increase; beets, 66 per cent.; hemp, 328 per cent.) that the French 
Department of Agriculture took the matter up from the scientific 
stand-point. . 
Execrriication THroucH THE Soin. 
‘The electrification of the soil has been attempted by many experi- 
menters for a considerable number of years. A common method is to 
pass a current of electricity from some external source through the soil 
between electrodes buried therein. In greenhouse work, not much 
success was obtained until the adoption of the carbon electrode, which 
does not react with the soil and the resulting products from electrolytic 
decomposition, as the earth acts as an electrolyte. A recent method 
that has good prospects is one in which electrodes are placed 6 inches 
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