88 



ANIMAL ELECTRICITY.— LECTURE IV. 



is rather instructive. During the passage of the 

 original current the reddening of the fluid occurred 

 only at the anode ; but now — i.e. a few moments after 

 the original current has been cut out, and only the 

 counter-current has been in play — there is also a slight 

 reddening of the fluid round the other wire ; this 

 wire, which was kathode or way-out from liquid as 

 regards the original current, is now anode or way-in 

 to liquid as regards the counter-current.] 



Experiment. — Beginning with K^ closed (to cut out 

 the battery ©) and K^ open, I first open and shut 

 the galvanometer key K3, to see that there Is no 



Fig. n 



current from the as yet unpolarised wires In the 

 polarisation cell. Leaving K3 closed (to protect the 

 galvanometer from the comparatively large battery 

 current about to be used, and which will be 

 through the cell and would be through the galvano- 

 meter as shown by the arrows) I polarise the 

 electrodes for a moment by opening K,. FInall)\ 

 I switch off the battery by closing K„ and switch 



