RELIGHTING OF THE CARBON AKC, 227 
q 
i=) 
oS) 
Ss 
Potential difterence between Carbons at make of crcuit in Volts. 
90 
0 | -2 3 
Interval between break and make of circuit in Seconds. 
6. Photographs of the relighting._By arranging an 
additional lever, in connection with the pendulum apparatus 
previously described, to open the shutter of a photographic 
camera at a short interval after the remaking of the con- 
nections of the arc circuit, photographs showing stages in 
the development of the arc have been obtained. The growth 
of the arc takes place in such a short time that a definite 
adjustment of the lever was found to be impossible, and 
the photographs given are only a few of many that have 
been taken, the remainder showing either no arc or the arc 
fully developed. 
Figures 1 to 7 in Plate 37, show stages in the growth of 
the arc when the circuit is opened and reclosed without 
alteration of the battery connections, while figures 8 to 11 
refer to cases where, on the reclosing of the circuit, the 
still existing crater is negative to the previous cathode. 
In both instances the glow is seen to develop from the 
electrode which is positive on the remake of the connec- 
