84 OF VITAL MOTION. 



the more frequent occurrence of spasmodic attacks at 

 night than during the day time. The second is the 

 pale and flaccid appearance of the muscles, which is a 

 common condition in convulsive diseases a fact which 

 may possibly show that the absence of light (for light 

 is infinitely concerned in healthy nutrition,) has had 

 something to do in inducing that state of muscular 

 fibre in which there is a proneness to contraction. 



The influence of electricity in muscular 

 action is very marked, but the manner of operation is 

 difficult and hard to be understood. If, however, we 

 investigate the late discoveries in this department of 

 science, and especially those of Matteucci, we find 

 reason to believe that the action of electricity, when 

 more fully known, will present no essential difference 

 from that of the correlative agents with which we are 

 already familiar. 



It is an initial fact in these inquiries, and one that 

 may very easily be tested, that there is in the muscles 

 of an animal during life, and so long after death as 

 the irritability continues, an electric current from the 

 interior to the exterior of the muscles, and in the 

 limbs, from the extremities towards the head. The 

 latter current, which is particularly conspicuous in 

 the hinder limbs of the frog, is of infinite importance 

 in the interpretation of the influence of electricity in 

 muscular action, and our first step must be to acquire 



