176 rHYSIOLOGY OF xNEKVES ASD MUSCLES. 



CHAPTEE X. 



1. Diverting arclics ; 2. Current-curves and tension-curves ; 3. Di- 

 verting cylinders; 4. Method of measuring tension differences 

 by compensation. 



1. If the two ends of a bent wire are applied, in 

 the way described in the last chapter, to any conductor 

 which is traversed by currents, then part of the currents 

 present in the conductor may flow through this wire. 

 Part of the current is, as it were, conducted out of the 

 body in order to facilitate its examination. Under 

 certain circumstances this may cause an alteration in 

 the conditions of the currents within the conductor. 

 We will, however, assume that this is not the case, 

 but that the tensions at the points at which the wire 

 is applied to the conductor are not altered.' The 

 direction and strength of the current which arises in 

 the conductor will then depend only on the differences 

 in tension at the point of contact, and on the resistance 

 offered by the wire. 



A wire of this sort applied to a conductor tiaversed 

 by currents is called a diverting arch ; the ends of the 

 wire with w^hich it touches the body to be examined 

 are called the feet of the arch; and the distance be- 

 tween these feet is called tlu distance of tension, 



' The circumstances under wliich the excoptions occur cannot 

 be explained here ; yet matters may be so arranged that such excep- 

 tions do occur. 



