THE ELECTROMOTIVE PHENOMENA 303 



shown by the capillary electrometer. Place 

 muscle A in the moist chamber upon two non- 

 polarizable electrodes. Let the tendon rest on 

 one electrode and the equator on the other. Lead 



Fig. 50. The vibrating interrupter. A platinum wire on the end of a steel 

 spring dips into a mercury cup. By varying the length of the spring, con- 

 tacts from once a second to more than one hundred per second may be 

 secured. 



from the non-polarizable electrodes through a 

 closed short-circuiting key to the capillary elec- 

 trometer (the tendon should be connected with 



