viii ELECTRO-PHYSIOLOGY 



Fifteen years have elapsed since the last review of the sub- 

 ject by Hermann, in his Handbuch der Physiologic an interval 

 sufficient, after the rapid advances in this department, to make 

 a new account desirable. The monographs are so scattered, and 

 in some cases so little accessible, that it is difficult to obtain 

 a synopsis of them. I have worked so long and zealously at 

 this particular department, and have in preparation for my 

 Lectures acquired a familiarity with its literature (which might 

 otherwise have escaped me), so great, that at last I believe myself 

 justified in venturing on the experiment of giving a comprehensive 

 survey of Electro-Physiology a task in which I am only too 

 well aware of my shortcomings. Notwithstanding, I venture to 

 hope that I have rendered a service, not merely to many of my 

 colleagues, but also perhaps to a portion of the medical public, 

 since I have aimed at a connected review of fundamental facts, 

 and have only introduced details of experimental method, and 

 pure theory, where they were indispensable to an understanding 

 of the subject. The chapter on Electrical Fishes in particular is 

 commended to the indulgence of my fellow- workers ; it could only 

 be compiled from the results of others, as I have no first-hand 

 experiences to draw upon. Those who know its widely-scattered 

 literature must condone the defects of the present attempt, in 

 view of the lack of any other summary. As an excuse for the size 

 of the work I may state that it has grown out of my lectures, 

 and could only thus escape a certain pedagogic dryness. In 

 justification of the sections treating of Histology and General 

 Physiology, I may be allowed to point out the intimate relations 

 between structure and function in muscle, nerve, and electrical 

 organs, as well as, on the other hand, the necessity of premising 

 the discussion of more special questions, with the general con- 

 ditions and forms of manifestation of activity in irritable tissues. 

 Hence it seemed to me not merely desirable, but imperative, to 



