4 ELECTRICAL STRUCTURE AND 



or in motility are probably connected with the dis- 

 turbance of electrical equilibrium. The fluids of different 

 chemical properties in adjoining cells, their decomposition, 

 the evolution of oxygen from cells containing chlorophyll, 

 the formation of carbon dioxide in growing organs, and 

 the process of transpiration all these vital processes must 

 produce electrical currents ; although this fact has not yet 

 been experimentally determined or accurately investigated." * 



Two of the greatest authorities upon Vegetable 

 Physiology are, or were, Sachs and Strasburger, although 

 equally valuable work has been done by Vines and Green. 



Sachs, in his twelfth lecture, said : " That electro- 

 motive mechanisms are present in the normal life of the 

 plant itself may be in part directly demonstrated, in part 

 presumed on general grounds. It has been established, 

 for instance, that every movement of water in a tissue, 

 even in the woody mass, is connected with slight electric 

 disturbances ; and that these even appear when dis- 

 placements of water are caused by the mere passive 

 bending of a portion of a plant, or by movements of 

 irritability on its part. In addition we may assume that 

 the chemical processes in nutrition, continually going on 

 in the plant, and the molecular movements during growth 

 and the passage of fluids from place to place, are all 

 connected with electrical disturbances of various kinds, 

 although it has not been possible to demonstrate this 

 experimentally. We may also suppose that in the 

 ordinary life of land-plants especially, during the con- 

 tinually altering differences of electrical tension between 

 the atmosphere and the soil, equalisations take place 

 through the bodies of the plants themselves. The land- 

 plant rooted in the soil offers a large surface to the air by 

 means of its branches, and the roots are still more closely 

 in contact with the moist earth, while the whole plant is 



* The italics are mine. 



