512 



Mr. A.,W. Ashton on the 



Table III. — Readings of Discharge from Okonite 

 Cable on April 10, 1900. 



5 minutes' Charge. 



10 minu 



tes' Charge. 



40 minutes' Charge. 



Time in 



Current in 



Time in 



Current in 



Time in 



Current in 



seconds. 



Amps. X 10-8. 



seconds. 



Amps. X 10 -S. 



seconds. 



Amps. X 10-8. 



37 



3-80 



46-5 



3-80 



40 



5-15 



49-5 



304 



59 



325 



52-5 



4-39 



575 



266 



71 



2-87 



67 



383 



70-5 



2-30 



85 



2-49 



81 



3-45 



86-5 



1-955 



96 



2-31 



100-5 307 





108 



212 



112 



2-88 



Charging volts 1036. 



125 



1-94 



127 



2-69 



.Temp. 13°-83 C. 







143 



2-50 





Charging 



volts 103-6. 



163 



2-32 





Temp. 



13°-83 C. 



189 



213 









! Charging volts 103-0. 









Temp. 13°-83 C. 



The equations are similar in form to those obtained from the 

 experiments on March 28th and 30th, and the constants are 

 of nearly the same value. In fig. 9 are given the readings 

 obtained by charging the okonite cable at 104, 206, and 

 337 volts. The equations obtained are : — 



(1) at 104 volts : 



c-3-90 x 10~ 8 = E x 32-2 x lO" 10 *- 461 . 



(2) At 206 volts : 



c-6-30 x 10" 8 = E x 28"2 x 10- 10 *- 422 . 



(3) At 337 volts : 



c _10 4xl0- 



:Ex30'7xl0- 10 t- iS \ 



The values of the quotient obtained when the constant 

 part of the current is divided into the charging pressure 

 are : — 



(1) For 104 volts.— 3320 megohms. 



(2) For 206 volts.— 3270 megohms. 



(3) For 337 volts.— 3240 megohms. 



These values are therefore nearly the same for the three 

 different pressures ; unfortunately the exact comparison is 

 not possible owing to the difference in the temperature of 

 the cable. A summary of the results obtained from the 

 okonite cable is given in Tables IV. and V. (p. 514). 



