ANIMAL ELECTRICITY. LFXTURE I. 7 



First Representative Experiment (on Muscle), — 

 This isolated muscle — it is the living muscle of a 

 dead frog — is connected with the galvanometer by 

 two electrodes touching it at two points T and L — its 

 tendinous end or transverse section, and its longitudinal 

 surface (fig. 4). As it stands, and though it has been 

 prepared as gently as possible, it is in all certainty 

 not absolutely uninjured and normal, therefore in all 

 certainty not homogeneous and electrically indifferent 

 at all points. It is living, that is to say it is dying — 

 for life is essentially slow death — and it is dying (or 

 if you prefer it living) in any case chemically changing, 

 more rapidly at its thin end T than at its thick part L. 

 If so — and for the purpose of making quite sure, I 

 may make it so by a touch of a hot wire — T will be 

 zincative to L, and we shall have current as shewn 

 by this diagram, illustrating on muscle that active 

 matter — in this instance stirred up by injury — is 

 zincative in relation to less active matter, crivinof 

 thereby a current of animal electricity. 



This has been the first half of the experiment. 

 Its complementary half, illustrating the same principle, 

 will complete it and fix its meaning to you. The 

 nerve through which this muscle was controlled when 

 it was in its place in the body, has been carefully 

 dissected out and protected from drying so that it 

 is still alive. Its far end from the muscle is stirred 

 up by weak faradisation, and you see that the muscle 

 contracts — telling you by its contraction that it and 



