ELECTRICITY AND MOVEMENT 279 



(/) Electrical Hypotheses of Velten and Fol 



The opinion frequently expressed by older observers, 

 namely, that protoplasmic movements depend upon elec- 

 trical forces, was defended again by Velten in 1876. 

 According to him it is electrical forces, which reside in, 

 and take origin from, the individual cells, that cause the 

 streamings. Velten supported this supposition, and his 

 view cannot be termed anything else, since he is not able 

 to elucidate either the origin or the mode of action of these 

 forces in bringing about protoplasmic movements, by his 

 observations upon the effect of strong induction-currents on 

 plant cells after death. Under these conditions he was able 

 to call forth streamings and rotations in the dead contents, 

 or rather on their granular enclosures (starch granules, etc.), 

 which were very similar to the natural streamings of proto- 

 plasm. The fact that we are dealing with phenomena 

 in dead cells, and further also the possibility that these 

 processes of movement produced by strong electric currents 

 might be in part at least the result of a considerable 

 increase in temperature in the cellular tissue subjected to 

 the currents which Velten does not take into account at 

 all, although he himself estimated the rise of temperature 

 at 65 or more, this fact in itself makes the value of these 

 observations seem very little for forming an opinion upon 

 the streaming phenomena of living protoplasm. It was 

 without doubt in consequence of this that Velten's view 

 met with no support at all. Eeinke in 1882, by means of 

 a series of interesting experiments, sought to directly contra- 

 dict the basis of Velten's supposition, namely, the presence 

 of electric currents crossing one another in the cell, in the 

 same way as Becquerel (1837) had already undertaken to 

 do by means of other methods in the case of Cham. Eeinke 

 showed, for instance, that the closely approximated poles of 

 a strong electro-magnet, between which are brought cellular 

 filaments of Chara or Nitella, or hairs of Urtica, suspended 

 freely in a drop of water, exert no directive influence upon 

 the position of the filaments. If electric currents really 

 moved in cells with flowing protoplasm, it might have 



