259 



TRAXSVERSE ELECTKOSTATIC FIELD. 



The uuiguet was then removed and the deflection of the discharge 

 studied in an electrostatic field. Witli the apparatus as previously de- 

 scribed and with the electrostatic plates, the points and the electroscope 

 shunted in parallel circuit, the four series of photographs I, J, K and L 

 were taken. The following is a record of the potential and the current 

 in each case, the forms of discharge for series I, J. K and L corresponding 

 to those of A. B. C and D respectively : 



Distance between iioints. IS.O:" nun. 



Table 3. 



No. in 



Series 



Charge 



on 

 bottom 

 Plate 



Sign of 



Right 



hand point 



Potential 



in 



Volts 



Current 



in 

 Amperes 







1 



none 



+ 



17850 



.00019 







2 



-t- 



i- 



17700 



.00019 





I 



3 



— 



■-1- 



17600 



.00016 





4 



none 



— 



16270 



.00016 







5 



. -\- 



— 



1.5150 



.00015 







6 



1 



— 



— 



16270 



.00015 







none 



i- 



18900 



.00027 







2 



-h 



-f- 



19425 



.00036 





J 



3 



— 



+ 



19500 



.00036 





4 



none 



— 



14700 



.00026 







5 



+ 



— 



17400 



.00026 





' 



6 



— 



— 



17250 



.00026 







1 



none 



+ 



16800 



.00039 







2 



+ 



+ 



17700 



.00051 





K 



3 



— 



+ 



19200 



.00052 



Changed to brush. 



4 



none 



— 



15600 



.00052 







5 



+ 



— 



17900 



.000.52 







6 



— 



— 



18370 



.00051 



Partjally changed to brush. 





1 



none 



+ 



16725 



.00092 







2 



+ 



■ + 



18000 



.00089 





L 



3 





+ 



17700 



.00091 





4 



none 



— 



13950 



.00088 







5 



+ 



— 



16875 



.00094 







6 



" 





16800 



.00090 





The variation of the potential and current in any series in the above 

 table except for (3 and 6) K, was due to a decrease of speed of the motor. 

 This was caused by a drop in potential when a large current was used in 



