SCIENCE AND INDUSTRY. 
ne 
It was Lemstrém who first suggested, from his observations on the 
growth of cereals under the influence of the Aurora Borealis, that the 
beards on the ends of most of the cereals might be a means where} 
small charges of electricity are collected from the air and transmitteg 
to the plant. He even contrived apparatus to prove the presence and 
measure the amount of such electricity round the grains. 
Newman-Lopce Merruop. 
Lemstrém’s methods were displaced by the Newman-Lodge high - 
tension system, and this is the method now adopted for most overhead 
discharge experiments. The current from a small dynamo, or from a 
THE INTERIOR OF THE SHED IN THE FIELD, SHOWING 
; HIGH-TENSION APPARATUS. 
town supply if available, is used to produce an alternating current by 
means of an induction coil. The negative current from the coil is led 
to the earth, while the positive current passes through a series of five or 
six vacuum globes, or Lodge rectifiers, and then to the overhead wires. 
The rectifiers work the pressure up to 100,000 or more volts. A system 
cf poles is arranged round the field, one to the acre. Each pole is 
capped with a large porcelain insulator, and No. 18 galvanized wire is 
fixed round the field. Finer wires are stretched across at intervals of 
30 feet, and about 15 feet above the ground. 
This method has been followed generally since its introduction by 
J. E. Newman, of Gloucester, and Sir Oliver Lodge, on the property 
26 
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