ON PHYSIOLOGICAL PHENOMENA. 221 



be dependent upon the power of the will of the animal ; 

 but even in this extraordinary fish, it is only under pe- 

 culiar conditions that the electrical excitement takes 

 place, and "what they inflict, they feel" during the 

 restoration of that equilibrium which is necessary to 

 their healthy state. Ill every case, therefore, we see 

 that some power far superior to this is the ultimate 

 cause ; indeed, light and heat, and probably actinism, 

 appear to stand superior to this principle ; and on these, 

 in some combined mode of action, in all probability, 

 sensible electricity is dependent. Beyond even these 

 elements, largely as they are engaged in the organic 

 and inorganic changes of this world, there are occult 

 powers which may never be understood by finite beings. 

 We advance step by step from the most solid to the 

 most ethereal of material creations, and we examine a 

 series of extraordinary effects produced by powers which 

 we know not whether to regard as material or imma- 

 terial, so subtile are they. On these, it appears, we 

 may exhaust our inductive investigations we may dis- 

 cover the laws by which these principles act upon the 

 grosser elements, and develope phenomena of a very 

 remarkable kind which have been unobserved or mis- 

 understood. Whether light, heat, and electricity are 

 modifications of one power, or different powers * very 

 closely united in action, is a problem we may possibly 

 solve ; but to know what they are, appears to be beyond 

 the hopes of science; and it were idle to dream of 

 elucidating the causes hidden beyond these forces, and 

 by which they are regulated in all their actions 011 dead 

 or living matter. 



M. Du Bois Raymond, from a series of researches 

 remarkable alike for their difficulty and the delicacy 

 with which they have been pursued, draws the following, 

 amongst many others, as his conclusions as to the cor- 

 nection of electricity and vital phenomena. 



The muscles and nerves, including the brain and the 



