42 Biology of Bacteria 



98.5 C. The antiseptics produced by electrolysis during 

 this time are not sufficient to prevent the growth of even 

 non-spore-bearing bacteria. The effect is a purely physical 

 one. 



2. A continuous current of 48 milliamperes passed through 

 bouillon cultures for from two to three hours does not kill 

 even non-resistant forms of bacteria. The temperature 

 produced by such a current does not rise above 37 C., 

 and the electrolytic products are antiseptic, but not germi- 

 cidal. 



3. A continuous current of 100 milliamperes passed 

 through bouillon cultures for seventy-five minutes kills all 

 non-resistant forms of bacteria even if the temperature 

 is artificially kept below 37 C. The effect is due to the 

 formation of germicidal electrolytic products in the culture. 

 Anthrax spores are killed in two hours. Subtilis spores 

 were still alive after the current was passed for three hours. 



4. A continuous current passed through bouillon cultures 

 of bacteria produces a strongly acid reaction at the positive 

 pole, due to the liberation of chlorin which combines with 

 oxygen to form hypochlorous acid. The strongly alkaline 

 reaction of the bouillon culture at the negative pole is due 

 to the formation of sodium hydroxid and the liberation 

 of hydrogen in gas bubbles. With a current of 100 milliam- 

 peres for two hours it required 8.82 milligrams of H 2 SO 4 

 to neutralize i c.c. of the culture fluid at the negative pole, 

 and all the most resistant forms of bacteria were destroyed 

 at the positive pole, including anthrax and subtilis spores. 

 At the negative pole anthrax spores were killed also, but sub- 

 tilis spores remained alive for four hours. 



5. The continuous current alone, by means of Du Bois- 

 Reymond's method of non-polarizing electrodes, and exclu- 

 sion of chemic effects by ions in Kruger's sense, is neither 

 bactericidal nor antiseptic. The apparent antiseptic effect 

 on suspension of bacteria is due to electric osmose. The 

 continuous electric current has no bactericidal nor antiseptic 

 properties, but can destroy bacteria only by its physical 

 effects (heat) or chemic effects (the production of bactericidal 

 substances by electrolysis). 



6. A magnetic field, either within a helix of wire or be- 

 tween the poles of a powerful electro-magnet, has no anti- 

 septic or bactericidal effects whatever. 



7. Alternating currents of a three-inch Ruhmkorff coil 



