Inductive Capacity of Electrolytes. 



193 



Table V. Turpentine. 



[Constant potential of 50 volts.] 



Table VI. Alcohol (temp. 22°'5. 



[Constant potential of 40 volts.] 



Distance 





between 



Deflexions. 



Electrodes. 





cms. 



cms. 



cms. 



025 





12 6-12 



0-5 



1 254 



ii 2-55 



10 



2 1-05 



10 1-06 



1-5 



3 -60 



9 -fil 



20 



4 '40 



8 -39 



2-5 



5 -27 



7 '27 



5-0 



6 -21 





Distance 





between 



Deflexions. 



Electrodes. 





cms. 



cms. 



cms. 



0-5 



6 1953 





10 



5 7-68 



7 7-78 



1-5 



4 4-41 



8 4-53 



20 



3 3-03 



9 3-06 



25 



2 2-21 



10 2-26 



30 



l 1-70 



n 176 



The plate cannot be set with anything like the accuracy 

 with which the distance between needle and plate can be 

 maintained constant, since the motion of the needle is 

 magnified by the telescope and scale over a hundred times. 

 Consequently the above measurements for variation of dis- 

 tance at constant potential are not as accurate as those pre- 

 viously given for variation of potential at constant distance. 



If these measurements be plotted out with distances and 

 deflexions as abscissae and ordinates respectively, we get two 

 curves resembling equilateral hyberbolas ; and if the ordinates 

 of the alcohol curve be shortened eight times, the two curves 

 will be almost indistinguishable. In other words, the rate of 

 variation of the force with the distance between the electrodes 

 is the same for turpentine as for alcohol (and water), and in 

 general is probably the same for dielectrics and electrolytes. 



3. Variation of Rate of Alternation of Potentials. — The 

 effect of change of speed of the commutator is generally small 

 and often inappreciable. With water the deflexion is greater 

 at higher speeds, although for quite pure distilled water the 

 difference is extremely small. For less pure water it is 

 larger, although not often more than 2 or 3 per cent., and is 

 probably due to polarization at the slower speeds. Not the 

 slightest trace of bubbles appears on the electrodes when 

 using moderately pure water, but with ordinary hydrant water 

 at rather high potentials bubbles appear at all speeds. The 

 needle is less steady at very low speeds, and when the 

 commutator stops the deflexion changes considerably and is 

 uncertain in amount except for very low potentials. It then 

 depends also on the direction of the current. These pheno- 

 mena were studied at some length, but as they seem to have no 

 direct bearing on the present question, further reference to 

 them is omitted. 



