Potts — Rowland *s New Method. 



99 



r' equal to the resistance of the hanging coil of the electro- 

 dynamometer. This avoided any sudden change of current 

 and hence a change of speed of dynamo. The key R 2 was the 

 chronograph key described above and was closed just at the 

 time the bridge was balanced. 











Table I. 















T = -00*75 



r = 



6535 



Calculated 



A 



Condenser. 



Ri 



R2 



R 3 



R4 



R'i 



R 1 — Ri 



3 





34-04 



2022 



4600 



99-7 



43-86 



9-82 



3 





34-45 



2020 



9090 



203-4 



45-22 



10-77 



2 





34-45 



2020 



2475 



99-7 



81-46 



47-01 



2, 



3 



[S]~: 



34-45 



2020 



8920 



407-0 



92-23 



57-78 



9 



3 



■F] — 



34-45 



2020 



2205 



51-7 



47-37 



12-92 



2 



3 



T]__. 



34-48 



1991 



4130 



99-7 



48-09 



13-61 



9 



-■> 



3 



rsi... 



34-19 



1992 



2031 



99-6 



97-83 



63-64 



3 





34-45 



1992 



3325 



99-6 



59-72 



25-27 



2 







34-49 



1992 



2414 



99-6 



82-28 



47-79 



A few measurements were first made using the paper con- 

 densers 2 and 3. Table I shows the results. In this and the 

 following tables, R'j denotes the effective value of R 1 calcu- 

 lated by formula (5) and A(=R 1 1 — R,,) the resistance due to 

 the electric absorption. T is the period of the current. The 





iff- 



20 ■ 



/^ 



15 s 



/^ 



10 ■ 



y^ 





s^ Cl 6-sciss<ie represent per-! c Js 



5 . 



%; — iti seconds- 





OrJmjtes represent electric 





<} I- sorption irj ohms. 



o-o 



■02 



•04 



•06 



•10 



■12 



results with these condensers was very unsatisfactory, as the 

 heating was so great that it was difficult to make accurate 

 determinations. 



r * The wax condenser made by Willyoung was next used. 

 This condenser had been made in a vacuum under pressure, 

 and showed quite small heating by the current. By taking a 

 series of measurements during an afternoon, the results were 

 not affected to any great extent by the changes in temperature 



