862 



SCIENCE. 



[N. S. Vol. II. No. 52. 



vail to-day to the fundamental concepts 

 which prevailed during the period preced- 

 ing Faradaj'. One of the most striking re- 

 sults which this comparison brings out is 

 the evolutionary development of new men- 

 tal concepts in the science of electricity, 

 going on hand in hand with the accumula- 

 tion of new physical facts. Faraday was 

 a rare combination of the discoverer and 

 the philosopher, capable of interpreting his 

 experimental discoveries in terms of broader 

 concepts suggested by these discoveries, en- 

 riching thus both our knowledge with new 

 physical facts and also our mode of scien- 

 tific reasoning concerning these facts with 

 new mental concepts. 



The concepts which Faraday first intro- 

 duced into the Science of Electricity form 

 the characteristic elements of the tenden- 

 cies of modern electrical research. A dis- 

 cussion of these tendencies means, there- 

 fore, a careful analysis of these modern 

 concepts. 



The two principal elements in our ideas 

 of physical phenomena are necessarily sub- 

 stance and force, that is the seat of phe- 

 nomena and the agent to whose activity the 

 phenomena are due. It is evident, there- 

 fore, that our ideas of electric and mag- 

 netic phenomena are, in a certain sense, 

 the same to-day as they were a hundred 

 years ago : that is, they are ideas of the 

 electric and of the magnetic forces, and of 

 the substances in which these forces dis- 

 play their activity. But although these ideas 

 relate to the same concepts, their form to- 

 day is vastly different from the form which 

 they had a hundred years ago; and obviously 

 so, because our ideas concerning forces and 

 substances in general are much broader 

 now than they were then. ■ 

 ■ The prototypes of our ideas of forces and 

 substances are of course our mental concepts 

 of mechanical force and of ponderable mat- 

 ter, and the Science of Mechanics is, there- 

 fore, the foundation of all exact physical 



sciences. The Science of Electricity is in 

 more than one sense an extension of the 

 Science of Mechanics, or rather of Dynamics. 

 To this, the oldest and formally most perfect 

 of all exact physical sciences, the Science 

 of Electricity owes its terminology, its defi- 

 niteness, and its elevation to the level of an 

 exact science. Necessarily so, for the most 

 satisfactory quantitative measure of any 

 accidental qualitj^ of matter, like electrifi- 

 cation or magnetization, is the mechanical 

 force which accompanies this quality. Thus 

 the history of the Science of Electricity as 

 an exact Science dates from 'Cavendish's 

 Coulomb's and Ampere's discoveries of 

 the law of mechanical force between elec- 

 trified or inagnetized substances, and be- 

 tween conductors carrying electric currents. 

 The concept of force is to-day and it al- 

 ways was the inseparable bond of union 

 between these two sciences. But just as the 

 history of Mechanics is simply a record of 

 the evolutionary development of our ideas 

 of mechanical force, similarly the history 

 of the Science of Electricity is the history 

 of the continuous expansion of our views 

 concerning electric and magnetic forces. 

 It is owing to this expansion that an ap- 

 parent emancipation of the younger sci- 

 ence from the older has taken place. 



We are becoming more and more familiar 

 with the modern division of the Science of 

 Physics into Physics of Ether and Physics of 

 Ponderable Hatter. A closer examination of 

 this modern division of Phj'sics brings us 

 face to face with one of the most important 

 modern scientific doctrines. This doctrine, 

 broadly considered, states that just as the 

 Science of Mechanics is the foundation of 

 physics of ponderable matter, so the Science 

 of Electricity is on the eve of becoming, if 

 it has not already become, the foundation 

 of Pliysics of Ether. The existence of this 

 doctrine is the most forcible expression of 

 the tendencies of modern electrical research. 

 Such a division is not only permissible and 



