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Drs. Crehore and Sqnier on the Currents 



points in the diagram move with a gradual change in the two 

 inductances, provided always the galvanometer remains at 

 zero. Fig. 5 illustrates this variation, and shows that the 



Fig. 5. — Showing the variation of the points of fig. 4 as the inductances 

 L ; and L 2 vary. 



point P moves along the circle AZPY in the direction of the 

 arrow as the inductances L x and L 2 increase. The point M 

 moves upon the circle XMA in the direction of the arrow as 

 the inductances increase. The points H, C, and D move 

 along the circles ZHO, ACO, and DO as the inductances 

 increase. This diagram enables one to draw the true diagram 

 for any value of the inductances. The points do not move 

 on the dotted parts of the circles, but are limited to the heavy 

 portions. The diameter AX is at right angles to OA, and the 

 line PM produced passes through the point X. The triangle 

 APM is similar to itself in all positions, for the angle at P 

 must be constant and equal to arc tan L 3 &)/R 3 . Hence the 

 diameter AY makes an angle XAY with AX, equal to MAP. 



