1026 
PROFESSOR J. A. EWING AND MISS H. G. KLAASSEN 
tivelj. The zero was shifted a little before each cycle to separate the curves. Here 
the changes of current took place slowly, a pause being made at each of the marked 
points to allow the position of the reflected spot of light to be noted. The curves are 
sheared over to the right in consequence of the gap in the magnetic circuit under 
Fig. 25. 
1 Cell 
