W. M. Stine — Simple Compensated Shunt Box. 125 



On inspection it is seen that both the structural and analyt- 

 ical difficulties inherent in the usual form of compensated 

 shunts arise from the fact that the compensating resistances are 

 introduced into the circuit to be shunted. 



By re-arranging the connections 

 and attaching them to three part 

 sockets, a marked simplicity is 

 introduced into the calculations for 

 a given set of shunts. 



proceeding to investigate the 

 new arrangement of the resistances 

 and shunts clearly shown in the 



accompanying figure, — the resist- 

 ance of the galvanometer circuit 

 through shunting becomes succes- 

 sively R Ci , Rc 2 ,R C3 , and in general 



Si i ^ 

 — VWWl/VHA 



R, = 



(D 



Now write 









WWWV\r-K> 



Foi 



Q i==ri + r a + r 3 ) 



Q.= ',+r, [ (8) 



the shunt at C, the compensating resistance Q, is 



9 „ w .- 1 



Similarly 



and 



Q.=? 



Q 2 =» 



Q,=<7 



(9) 



(10) 



(ii: 



If n x has the values given above, 

 Q i = 0-999 g ) 



Q 2 = 0-99 g\ (12) 



Q 3 = 0-9 g) 



The values of r are found by subtraction between the equa- 

 tions of (12) as is readily indicated in equation (8) ; and are 

 r 1 = 0-009 g ) 



r 9 = 0-09 g\ (13) 



r % =0-9 g) 



Since only the galvanometer is shunted, the values of S 1? S 3 , 

 and S 3 are easily found. 



Armour Institute of Technology, 

 September 16, 1897. 



