251 



bes in their roots and the farther ascending of their saps 

 is produced by such tubes, it is easy to see that the favour- 

 able results, I have received and of which I have given an 

 account in tlie above mentioned publications, have been 

 produced by the drawing of the water (resp. plant-saps), 

 which is effected by the electrical current from the earth 

 through the vegetables to the insulated wire. 



The somewhat stränge behaviour of the influence- 

 machine in changing poles, when provided with Leyden jars 

 and the one pole united with the earth, every time it is 

 stopped and put in motion anew, had snggested to me the 

 supposition that it was indifferent which of the poles was 

 united with the wire-net. 



I was still of this opinion in 1898 and, not till a 

 thorough investigation of the behaviour of the machine, was 

 it clear that an effect was attained only in the case the 

 negative pole was united with the wire-net or the points. 

 During the experiments the machine, which was always 

 provided with Leyden jars, had one day its positive pole 

 united with the wire-net and the other day, its negative. 



The influence was, nearly without exceplion, a favour- 

 able one after my experiments in Burgundy, where I had 

 made the important experience that the plants, which before 

 under the influence of the electricity had gone back, needed 

 only artificial watering to make the influence favourable *) 



*) In a paper „Ueber den Einfliiss der Electricitäfc autPflanzen" 

 (Öfversigt; af kongl. Vet. Akademiens P'örhandl. 1899, n:o fi) Herr H. 

 Euler has had the kindness to accoiiut for my experiments on influ- 

 ence of the Electricity, on plants. He has, however, omitted to men- 

 tion two very important experiments, made in Burgundy, the one on 

 carrots, the ather on strawborries. The carrots had during all the 

 forogoing experiments gone back, but when they were wateredas much 

 on the experimental as on the contral field) they showed an increase 

 of 80 -g- per cent. The strawherries, which had always given favourable 

 results, were in the beginning much developed under the electric cur- 

 rent, but during a period of 8 warm and sunuy days they were so 

 changed that they after that dwindled away. Il is no doubt that the 

 result should have been very favourable, if they had been watered. 



