270 M. G. Quincke on Electrolysis, and the 



In both cases multiplier and quadrant electrometer indicated 

 the same deflections, v.hicli almost agreed witli the theoretically 

 calculated values, as seen in the following Table : — 



i 

 Substance." 



i 



i 



! 



w. 



Multiplier. 

 i. 



Electrometer. 



U — V. 



Observed, j Calculated. 



Observed. 



Calculated. 



1 



Metal 



400 mil. CuSO^ : 



Metal i 



200 mil. CuSO*. 



70m. u. 



do. 

 35 m. u. 



do. 





 138 

 136-7 

 217-9 

 212-7 



138 

 138 

 221-1 

 2211 



246-25 



185-5 



185 



143-2 



137 



185-5 

 185-5 . 

 148-4 

 148-4 



R = 23-l m. u. 



Other experiments gave similar results. It would follow 

 thence that metallic and electrolyzable resistances have the same 

 deportment. 



"When, by means of Wollaston's electrodes of thin copper wire, 

 two different sections of the solution of sulphate of copper were 

 placed in conducting communication with the pairs of quadrants 

 of the electrometer, while the electric current of a battery of six 

 cells passed through the solution, the electrometer showed a con- 

 stant deflection when the electrodes while at a constant distance 

 were moved parallel to the direction of the current, and were in 

 the corner or in the middle of a section. 



§61. 



The difference of the electrical potential, already mentioned in 

 § 57, which the positive and negative poles of a Grovels battery 

 show when the other pole is in connexion vrith the ground, is 

 very striking. The irregularities show themselves in the same 

 manner with Dellmann-Kohlrausch^s electrometer, as well as in 

 the Thomson^s quadrant electrometer, though the latter instru- 

 ment has the advantage of measuring the difference of the 

 electric potentials at two points of a conductor ; hence the 

 potential for a given point of the conductor may be 0. 



For the sake of an example I here give a series of measure- 

 ments obtained with a Grovels battery of six cells, freshly 

 put together with the greatest possible care : the porcelain 

 vessels of the single elements stood in a deep dry glass dish ; 

 the metal contacts were soldered and varnished with shellac; 

 the thin silver wires of the pairs of quadrants of the electrometer 

 were joined to the platinum and zinc plates of the first and last 

 elements respectively by means of thick cotton-covered copper 



