STRAIN ON THE PHYSICAL PROPERTIES OP MATTER. 



Experiment III. 



The current was reversed a number of times whilst the wire was vibrating, the 

 reversals being timed by a pendulum vibrating once in a second ; the same battery 

 power as before was used. 



Sxpei'iment IV. 



After the above reversals the magnetising stress was applied as in Experiment I., 

 the battery power being still the same. 



MAGNETISING solenoid not excited. 



