INTRODUCTION 7 



now, since we know that electricity can not be seen, that 

 the phenomena of the arc are not the same as those of 

 electrolysis and that the current is not carried by par- 

 ticles. That the arc is not an electrolytic phenomenon was 

 shown most conclusively by Weedon l and will be referred 

 to at a later time. We may, therefore, leave the earlier 

 work and give our attention to experiments of a somewhat 

 later date. 



1 Paper presented at the Electro-chemical Soc., at Washington, D. C. r 

 April, 1904. 



