408 EFFECT OF ELECTRICITY [Cn. XVI 



were nearer the positive electrode more advanced than those 

 which were nearer the negative electrode. 



The method of electrifying the air over the plants was 

 employed by CELI ('78), FREDA ('88, on Penicillium), and 

 LEMSTROM ('90). Their methods were somewhat dissimilar: 

 CELI discharged static electricity through a wire breaking up 

 into fine points over the growing seedlings and got increased 

 growth ; FREDA used a similar method with Penicillium 

 reared on bread but obtained no favorable effect ; LEMSTROM 

 conducted his experiments upon a larger scale, since he 

 covered a small part of a field of germinating barley with fine 

 parallel wires about a meter apart, provided with metal points 

 at intervals, and supplied with a current from a Holtz machine 

 during eight hours a day for over two months. In LEM- 

 STROM'S experiments the yield of the electrified field was 

 35% in excess of that of the unelectrified, and the quality of 

 the grain was better. These experiments, which extended 

 through several years, were carried on in various parts of 

 Scandinavia and in France, and generally resulted in a favor- 

 able effect upon the growth of malt crops. 



The method of eliminating atmospheric electricity was used 

 with success by GRANDEATJ ('79), who employed the method 

 of isolating seedlings in a wire cage referred to on p. 407. 

 The plants reared in the wire cage grew uniformly less rapidly 

 than similar plants reared outside. ALOI ('95) has confirmed 

 these results with the same method, using maize and bean 

 seedlings. 



On the other hand other investigators, preeminently 

 WOLLNY ('93), who used the methods both of increasing and 

 of eliminating atmospheric electricity, obtain only negative 

 results. Thus the whole matter stands, rejected on a priori 

 grounds by many, denied as a result of negative experiments 

 by others, but still apparently demonstrated by three lines of 

 experimentation, none of them, however, free from criticism. 

 There prevails a cautious scepticism concerning the validity 

 of the positive results obtained. 



Various explanations have been offered by those who accept 

 the positive results. FREDA, who found that Penicillium is 

 injured by the increased atmospheric electricity, attributed that 



