348 APPENDIX. 



of events starts again ; in the text this is called the 

 arrangement for the interrupted current. 



Moist Chamber. 



One form of moist chamber is shewn at A, Fig. 1. In 

 arranging a nerve-muscle preparation in it the femur 

 (/) is clamped (c), a hook is passed through the 

 lower tendon of the muscle, the hook is connected 

 with another hook fastened to the lever, and the 

 lever by means of its screw is shifted up or down 

 to bring it in a horizontal position. Moist blotting- 

 paper should be placed on the floor of the chamber, 

 further the nerve should be covered with blotting- 

 paper moistened with normal salt solution. 



The nerve is placed across electrodes such as those 

 shewn in Fig. 4. 



d 



FIG. 4. 



Non-polarizable electrodes. 



One form of these is given in Fig. 5 ; the pointed end 

 (ch. c) of the glass tube is filled with china clay 

 worked into a stiff mass with normal salt solution ; 



