PREFACE 



FROM the very beginning of Experimental Physiology, the mar- 

 vellous action of electrical currents upon excitable animal tissues, 

 and the electrical forces which, under certain conditions, proceed 

 from these tissues themselves, have again and again attracted the 

 attention of scientific men, and have given rise to a vast number 

 of experiments, which at the present day are still being prosecuted 

 in all directions. This is accounted for by the great significance 

 at first attributed to the action of electrical forces in the living 

 organism. And at a later period, when these anticipations had 

 not been fully realised, and the desired goal of a " physical " 

 explanation of muscular contraction, nerve conductivity, etc., 

 seemed farther off than ever, the multitude of facts meantime 

 discovered, together with the exactness of the methods of observa- 

 tion, and the conviction that perseverance in the familiar path 

 must eventually lead to the solution of some at least of the 

 countless problems of living matter, spurred the student on to 

 renewed endeavour. Moreover, there was a growing desire to 

 establish the many and successful applications of electricity in 

 clinical medicine on a firm and secure basis, and to found an 

 exact science of electro-therapeutics. Thus it has come about 

 that the literature of Electro-Physiology, in a wide sense, has 

 swollen to a bulk that practically debars any student who is not 

 a specialist from critical acquaintance with it. 



