ELECTRICITY AND TL ANT-GROWING. 73 



mischievous effect of the ultra-violet rays is dissipated. I consider 

 it to be established that lettuce cau be profitably aided by the 

 electric light, and it is very probable that many flowers can be 

 similarly benefited. Beyond this, I cau only say that the funda- 

 meutal principles involved are uow pretty clearly understood, and 

 that the near future should give us results of direct economic 

 value. 



II. The Application of Electricity, or Electric Currents, 

 TO Plant-Growing. There have been many attempts to determine 

 the effects of electrical currents or electrification upon growing- 

 plants. The initial experiment was made by Maimbray in Edin- 

 burgh, so long ago as 1746. He submitted two myrtle trees to the 

 influence of electricity, and found that their flowering was much 

 hastened. A number of experiments followed at intervals, but the 

 results were various and contradictory, and few conclusions can be 

 drawn from them, until Grandeau approached the subject in 1878. 

 It will be useful to take a very brief survey of these experiments, 

 although I caunot discuss them so confidently as I have the influ- 

 ences of electric light upon vegetation, inasmuch as I have made 

 no experiments in this direction myself. But the general trend of 

 the subject, may, perhaps, be determined sufficiently for our 

 present purpose. 



It is necessary, Ijefore proceeding to a discussion of the subject, 

 however, to say that the application of electricity to plant-growing 

 is of three general and more or less distinct types : 1 . The direct 

 application of the current to the individual plant, by means of 

 which the plant is electrified. 2. The application of electricity 

 to the soil. 3. Its application to the atmosphere. Unfortunately, 

 these distinctions are not always kept in mind in discussions upon 

 the subject, and erroneous conclusions seem to have followed the 

 confusion. 



1. Concerning the direct application of electric currents to 

 plants, little of an exact nature can be said. It is well known — 

 and my own experiments have shown it as well — that a mild 

 electrical discharge will often seriously injure plants. A few 

 discharges from a small Holtz machine will cause many herbaceous 

 plants to wilt, and if the application is continued for an hour or 

 so, the plant may die. On the other hand, there are various 

 instances recorded in which beneficial results have followed the 

 application of a mild and steady current, as shown in more rapid 



