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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



of the whole system so considerably that effective discharge ceases to 

 take place and the machine may even cease to excite. 



The Lodge-Newman method requires the use of apparatus that is 

 covered by patents, and inquiries as to installations must be directed 

 to the Agricultural Electric Discharge Company. From conversation 

 with Mr. Newman I am hopeful that this Company will turn its atten- 

 tion to the production of a small coil suitable for use with the valves, 

 and which will considerably reduce the cost of an outfit capable of 

 employment in small-scale experiments. 



When by some method the necessary high tension current has been 

 obtained, the next question is the production of the discharge over the 

 plants selected; and as this presents distinct problems in the case of 

 outdoor and indoor crops these two cases will be treated separately, 

 the simpler case of outdoor crops being considered first. 



Overhead Discharge on Outdoor Crops. 



The great advantage that the Lodge-Newman system possesses here 

 lies in the fact that the potential maintained being usually greater, the 

 wires from which the discharge occurs can safely be raised higher above 

 the crops, so that hoeing and other operations can be carried on amongst 

 the growing plants without interfering with the overhead network. 



The height of the wires is chiefly determined by the potential to 

 which they are charged. For horticultural work they need probably 

 never be taken to a greater height than 10 feet, and this height presents 

 no difficulty with the Lodge-Newman apparatus. With an influence 

 machine uqed, to generate electricity they would have to be brought 

 much nearer the ground. 



At Evesham, in the experiments upon Mr. Eaymond Bomford's 

 farm at Bevington, the wires have been kept at a height of some sixteen 

 feet and a satisfactory discharge still obtained. 



This overhead system of wires has to be carefully insulated from 

 all its supports so that the high potential given by the electrical appara- 

 tus may be maintained. If too much leak occurs down supporting 

 posts, the potential of the overhead system will fall, and in this point 

 lie some of the chief difficulties to be overcome in the experiment. 



The network is raised on stout poles, crowned by insulators of a 

 special pattern, but the charged wire is not permitted to touch the insu- | 

 lator, connexion being made through a considerable length of ebonite | 

 rod or other insulating material. This insulating material has in experi- 

 ments up till now kept the charged wire four feet or so from the post, 

 but Mr. Newman recommends that in future experiments this distance 

 he increased, as discharge is still apt to take place from the charged 

 wire across the air to the supporting pole, rather than direct to the 

 earth. 



The overhead network is usually supported by two main lines of 

 poles to which are connected in the manner just described two strong 

 thick wires ; these are placed on either side of the area to be electrified. ^ 

 Between these two wires and across this area, therefore, are stretched 



