Sparking Voltages in small gaps. 467 



experimental results there would appear to be good reason 

 for believing that the assumptions on which; figure 1 is based 

 -are substantially true. 



Fig-. 4. 



2 3 



Current in Primary. 



fe*21 



4- Amps. 



Before the curves shown in figure 4 can be fully appre- 

 ciated it is necessary to mention certain supplementary 

 details observed in the experiments. Taking any one of 

 the curves, the first point (i. e. the one at which sparking 

 just occurred with the least current in the primary) was 



