18 



HATCH EXPERIMENT STATION. 



[Jan, 



In Table II. is shown a similar series of experiments, with 

 moditioations in the strengths of currents and methods of 

 treatment. The currents, however, are reduced in all in- 

 stances Avith favorable results. Nos. 6 and 7 received dif- 

 ferent treatment from those shown in the preceding table. 

 In No. 6, termed atmospheric electricity, the current was 

 obtained from a pole 35 feet above the ground ; from the top 

 of this pole there projected 24 small copper points, distrib- 

 uted in two circles, the outer arc having a radius of 30 

 inches. The arrano-ement was similar to that shown in Fio;. 

 2, but not identical. The copper points were all connected 

 with a single wire leading to the copper plate electrode of 

 Box No. 3, the other electrode being grounded, as shown 

 at G. The electrical potential was not determined in this 

 experiment, but the deflection of the needle of a sensitive 

 galvanometer showed that a current was present in the 

 soil. 



In No. 7, copper and zinc plate electrodes were simply 

 connected together with a wire ; this formed a cell in itself, 

 and generated a current, usually about the optimum, which 

 could be readily read with the milammeter. The results of 

 the experiments are shown in the last column at the l)ottom 

 of the table. 



Table III. — Showing (he Effect of Cm'rent Rkctricity iqwn the Growth 

 of Badishes (^Bdplmniis aritiviis L.). Normal FluJits tdken as the 

 Standard at lf)0. 



[Duration of experiment, 3C days.] 



No. 



Treatment. 



Normal 



Direct current; one gravity cell'; cop- 

 per plate electrodes 



Amospheric electricity; copper plate 

 electrodes, 



TOTAI> 



Weight, in 

 Gkams, of — 



Roots. Tops 



TOO 

 800 

 900 



2,700 

 2,900 

 3,000 



Per Cent. 



gained in 



Weight of - 



Roots. Tops 



14.28 

 28.59 



7.40 

 11.11 



Total 

 Per Cent, 

 gained. 



8.82 

 14.70 



Total -weight, in grams :- 

 Of roots, . 

 Of tops, . 

 Of whole phnit, . 



