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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Cultures of Alfalfa bacteria {Pseudomonas mdicicola) and of 

 Bacillus megatherium also increased enormously under electrical treat- 

 ment. With a current of '3 milliampere colonies of the first -mentioned 

 increased to over 5,000,000 on the eighth day (control 50,217), and of 

 the second to 7,650,000 on the fifteenth day (control 32,000). 



But with this method zinc oxide increases in the jars and eventually 

 poisons the bacteria. 



A large increase of bacteria in milk was also obtained by a cur- 

 rent of '3 milhampere. This amounted to over 94,000,000 and over 

 83,000,000 per c.cm., whilst in milk not stimulated the increase was 

 not more than 7,000,000 and 6,000,000 per c.cm. Static electricity was 

 also used with milk bacteria. Thus, on June 11, three similar jars 

 with milk contained 8342 bacteria per cubic centimetre. On June 15, 

 one which was not electrified contained 9,876,000 per c.cm. ; the second, 

 charged with one spark (positive), contained 70,500,000; and the third, 

 v/ith one spark (negative), 79,600,000 per c.cm. 



But with higher charges (such as 100 sparks every hour, or three 

 times a day, or even once only) the bacteria were injuriously affected. 

 With the higher charges, in fact, the number of bacteria was reduced 

 from 219,250 per c.cm. to 481 (positive charge) and 266 (negative charge) 

 in five hours, whilst in the untreated jar the number had increased to 

 over 1,000,000. Still, even with the heaviest charges, it was not found 

 possible to suppress micro-organisms. The author states, however: 

 Undoubtedly the use of strong electrical currents is capable of 

 destroying bacteria and preventing milk from deteriorating, ' ' and * ' in 

 some tests made of electrically treated milk we found that souring was 

 delayed. ' ' 



Positive charges (static electricity) were found to stimulate the 

 growth of bacteria more decidedly than negative ones ; the same differ- 

 ence had been noted by the author in experiments on the growth of 

 seedhngs. 



In another experiment the author used boxes of fairly good loam 

 (8x8x8 inches) in which electrodes (strips of zinc and copper 

 8x8 inches) were placed at either end and connected by copper wires. 

 Unfortunately the number of bacteria diminished in these boxes, but 

 by a greater amount in those boxes which were not electrified. In 

 another case static electricity was used (twelve wires brought to a 

 similar box and attached to a metal bulb on a Topler-Holtz machine, 

 which was given 100 sparks once a week). In this case the bacteria 

 in the electrically treated soil increased from 4,506,700 per gm. to 

 27,756,000 in seven days, whilst in the untreated soil they only 

 increased from 1,097,290 to 1,960,780 per gm. 



Other experiments on yeast showed that, under the influence both 

 of static and galvanic electricity, a larger amount of carbonic acid v/as 

 given off by electrified yeast. 



In one case in four days (galvanic treatment) 1200 c.cm. of OO2 

 were given by the electrified, and only 50 c.cm. by the control yeasts. 

 The latent period lasted usually from 15 to 25 minutes ; it was followed 



