410 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



ranging from 10 per cent, to 91 per cent., can be secured by the appli- 

 cation of electric stimulus. His investigations and experiments covered 

 nearly all the ordinary vegetable food products, including rye, wheat, 

 oats, barley, peas, potatos, beet-root, carrots, beans, turnips, tobacco, 

 and flax. 



Other experimentalists have more or less confirmed Lemstrom's 

 results. The optimum voltage according to Berthelot is 5 volts ; accord- 

 ing to Sir J. Kenny it is 3 volts ; according to the Swedish investigator, 

 Hilfvengren, the optimum voltage varies with different plants and climatic 

 and soil environment,* which is obvious. But to the author the experi- 

 ments of his friend, Mr. J. E. Newman, appear to constitute the best 

 promise for practical success of any experiments applying only the 

 electro-static stimuli for field work. It is satisfactory to know that the 

 experiments have been applied to the soil of England. 



Mr. Newman employs the overhead discharge. According to Mr. 

 Priestley, Mr. Newman's arrangement is as follows : — 



Direct current is generated by a dynamo of some 2 h.p. ; the electrical 

 energy developed passes from the dynamo terminals through the primary 

 of a large induction coil with a make and break contact interposed in the 

 circuit ; the high-tension current is passed from the secondary of the coil 

 through rectifiers, one pole being connected to the overhead distributing 

 wires, the other pole being earthed. 



Large poles, some 5 yards high and equipped with insulators, and 

 placed in rows, separated by a distance of 102 yards, cause the current 

 to cross wires 12 yards apart, and the current is sent through the 

 wires at such a high tension as to secure a discharge at points all along 

 the line. 



Applied to wheat the following results were obtained : — 



Year 1906. 

 Bushels per acre. 



Electrified Non-electrified Increase 



Per cent. Per cent. Per cent. 



Canadian (Red Fife) . .35^ . 25^ . 89 



English (White Queen) . 40" . 31 . 29 



The electrified wheat was of a higher quality, containing by analysis 

 •080 per cent, average dry gluten. 



The author has just received from Mr. Newman the following 

 information relating to this year's crops : 



Strawberries planted in March. 

 Electrified Non-electrified 

 223| lb. 2934 lb. 



from 11-725 yards. from 20*850 yards. 



* Berthelot claims that a difference of potential of 7 volts is sufficient to initiate 

 the chemical actions forming the basis of plant growth, and this slight potential 

 difference is capable of changing oxygen into ozone, and fixing atmospheric nitrogen 

 upon the carbo-hydrates constituting the tissue of plants. According to this savant 

 all these reactions will become so much easier and produce more intense effects in 

 proportion as the stalk of the plant is greater and the agitation of the air is 

 considerable. 



