Oscillations in the Discharge of a Leyden-jar. 



99 



successive discharges in the same direction slightly increase 

 the amount, but the needle soon reaches a steady state so 

 that the passage of any farther number of discharges has 

 no further effect. Care was taken to have a sufficient 

 number of discharges in one direction to reduce the magneti- 

 zation to a steady state before the direction of the current 

 was changed, and the same number of discharges took place 

 in the reversed direction. 



Fis:. 3. 



20 30 40 50 60 70 80 

 Length of Arc of Circle. 



The damping increases steadily with the length of the 

 spark, all the other conditions of the circuit remaining the 

 same/ The amount of this increase for a given range of 

 spark-lengths was found to differ according to the amount of 

 moisture in the atmosphere : the greater the moisture the 

 more uniform was the damping. The following table gives 

 the means of a large number of results on sparks varying 

 from 1 to 13 mm. in a moderately dry atmosphere. 



H 2 



