124 Rutherford: Modern 



province in which we can form a better estimate of his 

 intellectual eminence, clearness of vision, and philosophic 

 insight than in his original contributions to the then 

 infant science of electricity. My colleague. Professor 

 E. L. Nichols, has given you an interesting review of his 

 scientific work as a whole, and it now devolves on me 

 to point out the significance of his contributions to 

 knowledge in the special domain of electrical theory. 

 This may seem at first sight a relatively simple task, 

 but after emerging from the ordeal of preparing this 

 lecture, I can personally say with some confidence that 

 this is far from being the case. 



The theory of electricity developed by Franklin, gen- 

 erally known as the " one fluid " theory, must be re- 

 garded as the greatest of his additions to electrical 

 knowledge, for it has exerted a profound influence on 

 the development of electrical ideas, and, even after the 

 lapse of a century and a half of ceaseless activity in elec- 

 trical research, still holds its place, though in a modified 

 form, as the generally accepted explanation of the con- 

 nection between positive and negative electricity. 



In the course of this lecture I shall first endeavor 

 to outline the fundamental conceptions of Franklin's 

 theory, and then trace the gradual growth of our 

 ideas on the nature of electricity and the connection of 

 Franklin's theory with the views of electricity that are 

 held to-day. 



