1891.] 



the Discharge of Ley den Jars. 



The following readings give an idea of the range of adjustment 

 permissible; all the flashes in a horizontal line occurring simul- 

 taneously : 



Length of Sparks (in inches). 



Thus, with a long D spark, F could be anything up to nine-tenths 

 of an inch; whereas, with a short D spark, it failed at half that 

 distance. The jar-overflow is precipitated by a moderate A spark if 

 D occur too. D can be much longer than A. If both A and D are 

 long, the overflow is violent. 



Larger Jar. 



Now replace the first pint jar by one of the large " gallon " jars of 

 similar open shape, but with the glass protruding 4 inches above the 

 coatings, so that its overflow flash was 8 inches long. 



