ANIMAL AND VEGETABLE 201 



to any extent there would be defective storage, and if the 

 resistance of the insulating membrane in the condensing cell 

 were broken down or altered there would be a " fault.'* 



In works upon Physiology confusion is caused by the 

 uncertainty which attaches to the meaning of the words 

 "stimulus," "impulse," "irritation," and "charge" 

 when applied to nerve cells, but if it be accepted that the 

 natural impulse is neuro-electrical, and that the changes 

 which take place in nerve-cells and processes are due to 

 alteration of nerve potential, sign of nerve current, or 

 variations of external or internal resistance, a clearer 

 appreciation of the laws which govern the nervous system 

 may be obtained. 



In the same way we may find an explanation of uni- 

 polar, bipolar, and multipolar cells. The storage-ganglion 

 would be unipolar and the condenser-ganglion bipolar, 

 while a cell provided with two or more sets of alternatingly 

 conducting and insulating materials would naturally be 

 multipolar. Unfortunately the illustrations to be found in 

 works upon Physiology are not designed to show the 

 electrical structure of nerve cells and processes, and 

 therefore the difficulties in the path of the student are 

 great. That there is no book upon Biology or Botany 

 which gives any information upon the electrical structure 

 of any inhabitant of the vegetable kingdom is no longer to 

 be wondered at when some of the higher forms of life are 

 little understood. And yet, once the eye has been taught 

 to observe, that electrical structure is so clearly evident that 

 the most remarkable thing about it is the obscurity in which 

 it has remained. 



Some further light is thrown upon the function of the 

 storage-ganglia by the electro-cardiograms given by athletes 

 after strenuous physical effort has exhausted their reserves. 

 Nature has to generate nerve force to supply the immediate 

 requirements of the body, and as part of this is, and must 



