MORSE AND SHUDDEMAGEN. 



AN ALUMINIUM ANODE. 



381 



discharge time after a short charging time is different only in the 

 fact that the falling weight closes the charging circuit as it descends, 

 the remainder of the switches being thrown as already indicated. 



The data for Figures 8 and 9 was taken on the same plates as were 

 used in obtaining the A curves of Figure 6, and they show again the 

 fact to which attention was called at that point : the apparent ca- 

 pacity is, for all times of discharge, greater for a short time of charge 

 than for a longer one. The dotted 

 lines indicate full discharge. The 

 cell is left short-circuited through 

 the galvanometer to obtain this 

 value. 



For a plate similar to that 

 which gave the B curve of Figure 

 6 the A and B curves of Figures 8 

 and 9 will merely exchange po- 

 sitions. In this case a longer 

 charge corresponds to a greater 

 apparent capacity for all times of 

 discharge. 



Plates having charge -time 

 characteristics like those shown 

 in the AB curve of Figure 6 will 

 show a corresponding set of 

 discharge curves. 



The plate of Figure 8 was 

 formed at 140 volts, and both 

 the curves were taken with 



TO BATTERY 



TO GALVANOMETER 



TO CELL 



an 



Figure 10. 



Arrangement of switches for long 

 charge, long discharge, and varying short 

 applied voltage of 67 volts. The insulation times. 



plate of Figure 9 was formed at 



340 volts, and the working voltage was 195. 



5. Insulation Times. — Figure 10 shows the arrangement of switches 

 for the third of the time factors, variable periods of insulation. As 

 the figure is drawn arrangement is made for long charging times, the 

 upper switch being closed, so that the current passes from the charging 

 battery through the condenser until it is opened by the falling weight. 

 This opens all the circuits, and the cell is then closed through the 

 galvanometer after an insulating time depending upon the distance 

 between the two lower switches. Measurements with short charging 

 times were also made, and for this purpose a third switch is intro- 

 duced higher up, which is closed first of all by the falling weight. 

 Figures 11 and 12 give the results of these measurements for a con- 



