u 



HATCH EXPERIMENT STATION. 



[Jan 



Experiments with Radishes. 



Table I. — Showing the Effect of Current Electricity/ njwn the Growth 

 of Radishes (Itajthamis sativus L.). Normal Plants taken as the 

 Standard at 100. 



[Duration of experiment, 38 days.] 



1 Loss. 



Total average weight, in grams: — Normal. 



Of roots 4.83 



Of tops, 10.55 



Of whole plant, 15.38 



Per Cent. 

 Ti-eated. gained. 



5.12 6.00 



11.02 4.45 



16.14 4.93 



In Table I., in which six experiments are shown, three 

 normal and three treated, the results are not in every way 

 satisfactory. The current strengths were determined only 

 once or twice in each instance, and these were estimated by 

 means of the electro-motive force of the cell and resistance 

 of the soil, and also by a milammeter. The current strengths 

 given, therefore, represent only those which were found at 

 the time of the measurements ; and, since the resistance of 

 soil is constantly changing with the movements of the water 

 currents and with the ever-changing moisture conditions, 

 due to watering, the figures giving strengths of current must 

 not be considered as averages. The strengths of cm'rent 

 employed in the experiments shown in the first five tables 

 vary, probably from .05 to 1 milliampere. 



In the interrupted induced current experiments the cur- 

 rent had a duration of only about ten seconds per hour. 

 This was accomplished with a clock arrangement and with a 

 Du Bois-Reymond induction ap|)aratus. It should be pointed 

 out, however, that with the use of this apparatus only ap- 



