




DISRUPTIVE DISCHARGE OF ELECTRICITY. 683 
TABLE ITIT.—continued. 
| 
Deflection. Zero. | Difference. | Mean. 
n. n'. 
Upper Wire, Posi-| Heated, . 370 460 90 
tive and Heated ‘, 365 a! 95 ae 
i 365 x 95 " )2"9 
5 370 bh 90 J 
Upper Wire,Nega-| Before heating, 338 460 122) aS 
tive and Heated : F i cai 122 | 
Heated, . 375 | 5 85) 
» a0 PE et erat | 
. 365 ” | 95 > 84 
395 + 65 
+ 370 i. 90 





The wire when heated was always made red-hot, and the charging was made 
as soon after the heating as possible. A greater time elapsed between heating 
and charging in the first case than in the three others, owing to a less con- 
yenient arrangement of the battery ; which probably accounts for the compara- 
tively small effect. The observations of case second are plotted on diagram 3. 
They appear to show that the effect of a heating had disappeared before the 
time of the next heating, for they indicate a line parallel to the axis of a. 
When a continued spark was taken instead of a single, a similar diminution 
of the deflection was observed. 

Taste [V.—Continued Spark between Platinum Wires, 26th June 1878. 
Shortest distance between wires, 4mm. Positive wire operated on. 




| : Difference of | iffer 
Deflection. Zero Le Por, ae re Sti 
nN. N. : n’—n. Potential. 
Before heating, ( 390 535 495 145 
. | 380 530 - 150 | 
405 540 500 135 | Le) 
; 400 530 $ 130 } 
Heated, . ( 390 525 2 135 
E 4 390 530 A495 140 133 
% ( 380 505 Ps 125 
Heated longer, 4.15 55 Fd 100° 
415 515 » 100 98 
; (415 510 : 95 




VOL, XXVIII. PART II. 

