tuce, he prepared two plots in a greenhouse so that 

 they would be subject to like conditions and influ- 

 ences. In the one he buried, at a little depth in 

 the soil, a system of copper wires consisting of 

 series of from four to nine strands one half inch 

 apart. He connected the wires with a battery of 

 two cells, which sent a continuous current of elec- 

 tricity through them. These plots were in a part 

 of the greenhouse which had been used for the 

 raising of lettuce, and in which great trouble had 

 been experienced from mildew. One of his ob- 

 jects was to see if the electric treatment would 

 have any effect upon the mildew. Equal numbers 

 of healthy lettuce plants, of the head variety, were 

 set in the plots; those in the plot with the electric 

 apparatus were planted over the wires so that their 

 roots could come in contact with them. He re- 

 ported that five plants out of fifteen in the electric 

 plot were killed by the mildew, the other ten being 

 " well developed and the heads large." In the 

 corresponding unelectrified plot " only three plants 

 had partially developed, and two of them were 

 nearly destroyed by the mildew only one was free 

 from disease." It was noticed that when the cur- 

 rent became weak, or was interrupted, the heads 

 began to feel the destructive influence of the mil- 

 dew; also that the largest heads were over the 

 greatest number of wires and nearest where the 

 wires were attached to the battery. A strange 

 sight presented itself on examining the roots: it 

 was found that they had " grown about the wires 

 as if there they had found the greatest amount of 



