OP ARTS AND SCIENCES. 



235 



of observations made with the same diaphragms used in the experiment 

 last described gave the results shown in Tables IV., V., and VI., which 

 are in substantial accord with those reached with the earlier form of the 

 apparatus as given in Tables I., II., and III. From these tables the 

 curves shown in Figure 1 were constructed. The induced currents 

 are represented by abscissas, the strengths of the field by ordinates. 



Diaphragm, Sheet Iron, No. 22. 



Strength of Field. Induced Current. 



Strength of Field. Induced Current. 



The numbers 21, 22, 23, affixed to the curves of Figure 1, indicate 

 the thickness of the corresponding diaphragms by their gage number (B. 



