48 AGRICULTURAL RESEARCH AND THE FARMER : 



receive a much larger electric current from the atmosphere 

 than they get in more central regions. This view seems to have 

 been unfounded, but it initiated the experiments which have 

 since been conducted in various countries into the effect of 

 electrical discharge on the growth of crops. In the earlier 

 experiments carried out in this country the amount of electrical 

 discharge was not measured, and the value of the results obtained 

 was much lessened in consequence. In the experiments begun 

 at the Imperial College in 1916, special attention was paid to 

 the question of measurement. In 1918 a Committee was set 

 up by the Ministry of Agriculture and Fisheries to investigate 

 the whole subject thoroughly, and, as a consequence, the Imperial 

 CoUege has become mainly responsible to this Committee for 

 directing the investigations. The initial research into the effects. 

 of electrical discharge on the plant is done at the College. Pot 

 experiments with maize, barley and wheat are carried out at 

 the Rothamsted Experimental Station. Field experiments with 

 clover, hay, barley and winter wheat are conducted at Rotham- 

 sted, with oats at Lincluden, Dumfries, and with oats and clover 

 hay at the Harper Adams Agricultural College, Newport, Salop. 



The laboratory work at the Imperial College is an object of 

 fascinating interest to the visitor. Young seedlings are grown 

 in an enclosed chamber so cleverly insulated that its temperature 

 is kept constant throughout the day. The growing tip of the 

 seedling is subjected to a downward electrical current, kept 

 constant by means of the most sensitive galvanometer that can 

 be obtained. The growth of the tip is traced by means of a 

 microscope, and readings are taken at ten-minute intervals 

 throughout the day. The object of the investigation being 

 conducted at the moment is to find the ideal current to apply. 

 The maximum current— beyond which growth is adversely 

 affected — has already been ascertained, and at present the 

 current being used in the field experiments is about i milliamp. 

 per acre, which is about 100,000 times as strong as that supplied 

 normally by the atmosphere. It still remains to be discovered, 

 however, whether a smaller current may not be equally efficient 

 or even better. 



An analysis of the results obtained in the field since 1915 

 shows that with spring-sown cereals an increase of 22 per cent, 

 in the yield, or 7 bushels per acre, has been obtained as the result 

 of electrification. In four experiments with clover-hay, a 

 mean increase of 20 per cent., or 3I cwts. per acre, has been 

 secured. This evidence of the beneficial effect of electrical 

 discharge has been confirmed by the numerous pot culture 

 experiments that have been conducted. On the other hand„ 



