14 



BULLETIN 1379, U. S. DEPARTMENT OF AGRICULTURE 



cage of ^-inch mesh. The frame was connected to the positive 

 pole of the static machine, the other pole being grounded. The 

 frame was charged four hours a day, from 3 to 7 p. m., from February 

 21 to March 24. The plants were again allowed to grow without 

 treatment from March 25 to April 7. During each period weigh- 

 ings were made to determine the loss due to transpiration, and 

 water was added when necessary to maintain approximately the 

 initial moisture content of the soil. 



Table 17 shows the rate of transpiration for each pot during the 

 three periods and the ratio of the treated to the control set. It 

 will be noted that during the period of treatment no sensible change 

 occurred in the transpiration ratio. 



Table 17. — Transpiration rate of geranium plants in pots under electrocultural 

 treatment in the plant house at Washington, D. C, in 1913 





Transpiration rate per hour (grams) 



Pot designation 



No treatment 



Treatment period 



No treatment 





Feb. 15 



to 17 



Feb. 17 

 to 20 



Feb. 20 

 to 25 



Feb. 25 



to 

 Mar. 1 



Mar. 1 

 to 5 



Mar. 5 

 to 13 



Mar. 13 

 to 24 



Mar. 24 



to 

 Apr. 1 



Apr. 1 

 to 7 



Treated set: 

 No. 17.". 



3.6 

 3.3 

 2.9 

 2.6 

 4.3 

 2.1 



5.1 

 4.7 

 5.3 

 4.7 

 6.1 

 5.0 



5.1 

 5.1 

 4.8 

 4.4 

 6.4 

 4.9 



2.9 

 3.4 

 2.9 

 2.9 

 3.3 

 3.2 



8.3 

 8.4 

 8.1 

 7.7 

 9.7 

 7.9 



8.0 

 8.0 

 7.6 



7.4 

 7.9 

 6.8 



8.8 

 9.5 

 9.0 

 9.4 



7.7 

 8.7 



7.7 

 8.2 

 7.7 

 8.9 

 6.8 

 8.6 



10.5 



No. 176 



10.9 



No. 177 



10.9 



No. 178 



11.4 



No. 179... 

 No. 180 



10.4 

 11.4 









3.13 



5.15 



5.11 



3.10 



8.35 



7.61 



8.85 



7.98 



10.91 







Control set: 

 No. 181 



3.1 

 3.3 

 3.3 

 3.6 



4.3 

 3.6 



4.2 

 5.7 

 4.6 

 5.0 

 5.7 

 5.3 



4.3 

 6.0 

 5.2 

 4.9 

 5.9 

 5.5 



2.8 

 3.7 

 3.4 

 3.2 

 4.0 

 3.5 



7.0 

 8.6 

 8.1 

 8.0 

 9.0 

 8.7 



6.5 

 8.0 

 7.6 

 7.6 

 8.2 

 8.4 



8.4 

 8.6 

 8.9 

 8.9 

 8.1 

 8.6 



9.1 

 7.3 

 8.2 

 8.4 

 7.1 

 7.4 



11.1 



No. 182 



10.7 



No. 183 



10.6 



No. 1M 



10.9 



No. 185 



No. 186 



10.3 

 10.6 







Mean 



3.53 



5.08 



5.30 



3.43 



8.23 



7.71 



8.58 



7.91 



10.70 



Ratio of treated to control.-. 



.89 



1.01 



.97 



.91 



1.01 



.99 



1.03 



1.01 



1.02 



The total transpiration from the treated and control 

 geranium plants for the three experimental period 

 Table 18. 



d control sets of potted 

 is given in 



Table 18. — Total transpiration of geranium plants in pots during the three experi- 

 mental periods in the plant house at Washington, D. C, in 1913 





Total transpiration (kilo- 

 grams) 



Designation 



No treat- 

 ment, 



Feb. 15 

 to 20 



Treat- 

 ment 

 period, 

 Feb. 21 to 

 Mar. 24 



No treat- 

 ment, 

 Mar. 25 

 to Apr. 7 





3.00 

 3.08 



33.42 

 33.42 



20.01 





19.62 









.98 



1.00 



1.02 







