PREFACE 



THIS volume concludes the line of investigation on respon- 

 sive phenomena in general, which I commenced with the 

 publication of a Memoir l at the International Congress of 

 Science, Paris, 1900. In this first of my publications on the 

 subject I undertook to show the similarities of response in 

 inorganic and living substances. The method which I at 

 that time employed for obtaining my response-records was 

 that of Conductivity Variation. With the object of showing 

 that the similarity of response here demonstrated to exist 

 was due to some fundamental molecular reaction, common 

 to matter in general, and therefore to be detected by any 

 method of recording response, I next undertook to record 

 the Electro-motive Variation under stimulus. Believing, as 

 I did, in the continuity of these responsive phenomena, I 

 used the same experimental devices by which I had already 

 succeeded in obtaining the electric response of inorganic sub- 

 stances, to test whether ordinary plants also, meaning those 

 usually regarded as insensitive, would or would not exhibit 

 excitatory electrical response to stimulus. The stimulation 



1 ' De la Gene'ralite des Phenomenes Moleculaires produits par PElectricite 

 sur la Matiere Inorganique et sur la Matiere Vivante ' ( Travaux du Congres 

 International de Physique, Paris, 1900). See also ' On the Similarity of Effects 

 of Electrical Stimulus on Inorganic and Living Substances,' Report Brit^ Assoc., 

 Bradford, September 1900 (Electrician). 



