FIELD f'ROPS. 



631 



" Tho mothoc! is t<i sti"Otcli over the Jii'ld to he treated a number of wires on 

 poles, soinetiiues liice low telejjrraith wires, hut hifrh enou};h for loa(le<l wagons 

 and all the usual fanning operations to go on iniderneath the wires withojit let 

 or hindrance. The wires are quite thin, and are supported by a few posts in 

 long jtarallel spans, about .'{(» ft. ajiart. They are supi^orted on the posts by 

 elaborate high-tension insulators, and they extend over all the acreage under 

 experiment, a control plat of similar lands under similar conditions l)eing, of 

 course, left without any wires. 



"The system of conductors is then coiuiected at oiu' jiosl with ;i generator 

 supplying pofiitive electricity at a potential of something like a liundrtHl thou- 

 sand volts, and with sufHcient power to maintain a constant supply of <']ectricity 

 at this kind of potential. 



" Leakage inuniMli.-itely begins, and the charge fizzes oft' from the wires with a 

 sound which is sometimes audible, and with a glow which is visible in the 

 dark. . . . 



"The electrification is maintained for some hours each day, but is shut off at 

 night: it is i)robably only necessary to supply it during the early morning hoiu's 

 in suumier time, and in springtime or in cold cloudy weather for the whole day. 

 or during the time of the plant's greatest activity. But at what stages of the 

 growth of a i»lant the stimulus is most effective has still to be made out. . . . 



"The power re(piired to generate the electricity is very small, for although 

 the potential is high the quantity is insignificant, and the energy is accordingly 

 comparatively trivial. . . . 



"The electricity can ... be generated by the revolving glass plates of a 

 static influence machine, usually known ... as a Wiinshurst machine; or it can 

 l»e generateil by transforming up to high tension, and rectifying to one direc- 

 tion, the current of . . . a dynamo. Tlie first is in many respects the sinq)lest.'* 



Increases of 80 to 40 per cent in yield and improvement in (juality of wheat 

 due to electrification are reported. A Ho per cent increase in yield and earlier 

 ripening were observed in case of strawberries, and a 25 per cent increase in 

 yield and larger sugar content in case of mangolds. Improvement in growth 

 was oliserved in case of raspberries and tomatoes. Electrification was applied 

 for from (iOO to 1,000 hours in case of the crojts experimented with. 



Duty of water, (i. II. Trx^k (\rra(la »S7a. liul. CS. pp. 2'/, 2o). — The results 

 of ji study on the amount of water necessary to prfKluce farm crops are given 

 in the following table : 



/'(siills of II iiphiiii;/ raridiis iinioinils nf iriitcr to crniil crops. 



