192 



Mr. E. B. Eosa on the Specific 

 Table III. — Alcohol. 



Potentials, V. 



Deflexions. 



Squares ot - . 



Constant Quotients. 



5 volts. 



•11 cm. 



1 



•110 



10 



•48 



4 



•120 



15 



1-13 



9 



•125 



20 



203 



16 



•127 



25 



314 



25 



•126 



30 



445 



36 



124 



35 



607 



49 



•124 



40 



791 



64 



•124 



45 



9-98 



81 



•123 



50 



1239 



100 



•124 



55 



1504 



121 



•124 



60-75 



18-45 



147-6 



•125 



From these measurements it will appear that the force is 

 accurately proportional to the square of the potential for these 

 electrolytes as well as for dielectrics. 



Low Potentials. — With the more sensitive instrument 

 described below, measures of the force for lower potentials 

 were made. By bringing the needle quite close to the plates 

 (fig. 4) deflexions equal to those shown by the other instru- 

 ment were obtained by forces 50 times smaller. Two causes 

 tend to make the readings less accurate than before. First, 

 since the electrodes are nearer, small inequalities in their 

 distance produce a relatively greater effect. Second, the 

 force is found to vary much more for low potentials with 

 inequalities in the rate of alternation of the current. The 

 following table shows, however, that the force is still propor- 

 tional to the square of the potential : — 



Table IN.— Water. 



Potential, V. 



Deflexions. 



Squares of V. 



Constant Quotients. 



1-0 volt. 



•75 cm. 



1 



•75 



1-5 



1-7 



225 



•76 



20 



30 



4 



•75 



25 



4-75 



6-25 



•76 



30 



6-5 



9 



•72 



4-0 



12-5 



16 



•78 



50 



20-0 



25 



•80 



2. Variation of Distance between Electrodes. — In the 

 following tables the readings of the deflexions were made in 

 the order of the preceding numbers. 



