372 BOTANICAL GAZETTE [NOVEMBER 
electrically treated increased from 4,000,000 to 27,000,000. The soil 
in this case was freshly prepared and carefully mixed and contained 
more organic matter and plant food than the former; neither was there 
the same tendency for the soil to become badly compacted as in the 
preceding series. 
TABLE XII 
Showing the results of electrical stimulation on the bacteria in soil (static elec- 
tricity). 
NUMBER OF BACTERIA IN 18™ 
Date OF 
Normal Electrical 
Fuly Saree ois 1,097,290 4,506,700 
JO 4 30 960,000 15,208,000 
(Peg tol Allee ape 1,960,780 27,756,000 
The electrical experiments with soil were not continued, since the 
details associated with soil bacteriological analyses are laborious. The 
results of electrical stimulation of soil organisms are not so pronounced 
as in the case of the water and milk experiments, but the effects are 
clearly shown in table XII. 
Our numerous experiments in growing plants in electrically stimu- 
lated soils have demonstrated that considerable acceleration in germi- 
nation and growth follow when currents of optimum intensity (0.1 — 
0.6 milliampere) are employed, and all the forms of plant life are 
undoubtedly stimulated in a similar way. 
Influence of electrical stimulation on yeast 
Some experiments were made in our laboratory for the purpose 
of observing the effects of electrical stimulation on yeast, in which we 
endeavored to determine the relative activity of the normal and elec- 
trically treated organisms by the amount of CO, given off. 
As in the preceding series, we used galvanic currents obtained by 
the use of copper and zinc electrodes and also static charges from a 
Toépler-Holtz machine. Small bottles were used in the experiments, 
ranging from 2 to 4°™ in diameter and 12 to 16°™ high. The elec- 
_ trodes were 2°™ in diameter and were placed in the bottle containing 
the yeast and culture media. In the experiment with static electricity 
we made use of simple Leyden jars corresponding to those described 
