﻿208 Mr. A. Russell on the Dead Points of a 



Hence 0i - O = <?' + X0 O , 



f =fjuGq Q /Q/Lk*fi~R)V* 



= the throw in the symmetrical position, 



X = 7(7 o7{2KR(M^VH) ] /2 } . 



We see that whether q be positive or negative \ must be 

 positive. Hence we may write 



0i-0o= ±^+^o (5) 



where 



and 



TV/row < i 



70. 



/ftS/STAA/Ct 



Variation of the throw with the resistance in the discharging circuit. 

 Capacity one microfarad. Charging voltage 105. The equilibrium 

 position of the needle is one degree from the symmetrical position. 



In the figure the throws produced when the needle was 

 initially one degree from its symmetrical position are shown 

 for various values of the resistance in the discharging circuit. 

 The experimental curve in the figure is very nearly coincident 

 with the hyperbola whose equation is 



y= -12 + 432/(^ + 5). 



The resistance of the galvanometer and leads was one ohm, 

 the inductance of the galvanometer-coil 0*0021 henry, and 



