STIMULATION OF MUSCLE AND NERVE 133 



with normal saline solution. The larger electrode 

 may be fastened upon the arm or other indifferent 

 region, and the smaller may be used to stimulate the 

 nerves or muscles, for example the abductor indicis, 

 or to find the "motor points." 



Connect 8 dry cells in series (the carbon of 

 one cell to the zinc of the next, etc.). Coupling 

 in this way enables the electromotive force of 

 each cell to be added with slight loss to that of 

 the others, provided the resistance in the circuit 

 outside the cells is so great that the internal 

 resistance of the battery disappears in compari- 

 son, as is the case where living tissues form part 

 of the circuit. Connect the terminal zinc and 

 carbon pole through a pole-changer (with cross- 

 wires) to a small and a large electrode covered 

 with cotton thoroughly wet with strong saline 

 solution. Place the small electrode over the 

 ulnar nerve between the internal condyle and 

 the olecranon, a little above the furrow. Make 

 and break the current. If no contraction is 

 secured, add cells to the battery until contraction 

 occurs. 



It will be found that the first contraction 

 occurs on closure with the cathode over the 

 nerve. With this strength of current the opening 

 contraction will be absent. 



Turn the pole-changer so as to bring the anode 



