484 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



charging voltage, is 0.0032 of a second. But, by using a narrower 

 strip of lead for the north knife to plough over, this time can be short- 

 ened Again, two extra pairs of the lead strip holders were mounted 



TABLE VI. 

 "Mica B ". 



higher up on the north rod, so that the charging voltage could be 

 applied for longer times. This accounts for the residual-forming in- 

 tervals of 0.111 second and 0.57 second. For convenience in compar- 



TABLE VII. 

 " Par. B." 



ing results, values of the ballistic throws divided by the voltage are 

 given so as to show the residual charge left in the condenser after 

 short circuit, expressed in centimeters of throw per charging volt. 

 The ballistic sensitiveness of the d ' Arsonval galvanometer was such as 



