182 PHYSIOLOGY OK Ml'SCLES AND NKKVES. 



cylinder ". somewhat flattened, is attached to the stand 

 A. The Mu-ket i' :ind the motor apparatus on the 

 column // allow the glass cylinder to be placed in any 

 desired position. Within the cylinder i< a strip of 

 amalgamated sheet zinc b, which can lie connected 

 with the multiplier by means of a wire. The glass 

 cylinder is closed below with a stopper of plastic clay 

 inoi>tened with a solution of common salt, the project- 

 ing ends of which can be moulded into a point which 

 touches the suialle-i possible point on the conductor 

 to lie examined. The space within the glass cylinder 

 is filled with a concentrated solution of sulphate of 

 zinc, and thus forms an unpolarisable and homogene- 

 ous conductor between the strip of zinc and the clay 

 point. A second and exactly similar apparatus, which 

 is only partly represented in the figure, provides for 

 the divei>iou from the other point of the conductor. 



Whatever form of diverting apparat us i- employed, 

 the determination of the fact whether the two points 

 touched bv the feet of the diverting arch have like or 

 unlike tension will be more accurate the more sensi- 

 tive is the multiplier which is inserted in the diverting 

 arch. By placing the body to be examined in such a 

 \\-.\\ that the various points in its surface successively 



lie on the pads of the above-descril ied diverting vessel 

 (see ch. ix. , r >), or liy touching them with the ends of 

 the diverting cylinder ju-t mentioned, it may be dis- 

 covered which points have equal tension (for in such 

 cases the multiplier will indicate no deflect ion), or, if the 

 points touched are unequal in tension, it may lie dis- 

 covered at which the positive ten-ion i> great e>t. For, 

 from this latter point a current must pass through the 

 multiplier to the point at which Hie positive tension is 



