866 



SCIENCE. 



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



body to another, unless there is a material 

 connection between them. It is this view 

 of force which led to the formulation of the 

 Wave Theory of Light ; it is also this view 

 of force which gives us the nearest physical 

 picture of the modern view of electric and 

 magnetic forces. But the view of electric 

 and magnetic forces which prevailed dur- 

 ing the last century and during the 

 first part of this centurj' was that which 

 accorded with the scientific credo of the 

 Newtonian school. This is easUy accounted 

 for. The successful solution of many most 

 remarkable dynamical problems, like the 

 theory of tides, the figure of the earth, the 

 problem of planetary perturbations, etc., 

 commanded most profound attention. They 

 were just so many signal triumphs of New- 

 tonian dynamics and of the Newtonian 

 school. No one dared to doubt the infalli- 

 bility of anj'thing that seemed to have even 

 the remotest connection with Newton's 

 philosophy. The laws of action of Electric 

 and Magnetic forces, that is, the laws of 

 Cavendish, Coulomb and. Ampere, all fol- 

 lowed the rule of the inverse square of dis- 

 tance and resembled, therefore, Newton's 

 law of gravitation in a most remarkable 

 manner. It is, therefore, not at all sur- 

 prising that the doctrine of direct action at 

 a distance, which seemed to have done so 

 much good in the theory of gravitation, 

 should have been transferred bodily into 

 Science of Electricity and Magnetism. 



But the victorj^ of the Undulatory Theory 

 of Light, revived by Young and Fresnel, 

 over the corpuscular theory lessened con- 

 siderably ■ the confidence in Newton's un- 

 questioned authority and in the correctness 

 of the doctrines of the so-called Newtonian 

 school. Besides, this Undulatory Theory 

 brought into conspicuous prominence a new 

 form of matter which was independent of 

 that mysterious attribute, the gravitating 

 force that acts directlj' at a distance ; a 

 substance permeating all space, even the 



innermost interstices of ponderable matter, 

 and capable of transmitting actions between 

 material bodies with enormous velocity. 

 Add to this the invention of the steam en- 

 gine and the discovery of the galvanic cell, 

 the operations of which had no apparent 

 immediate connection with anj' formal laws 

 of Newton's dynamics or with Coulomb's 

 and Ampere's distance laws of electric and 

 magnetic force and the scientific atmos- 

 phere at the beginning of this century will 

 appear to us in its true light, that is, full of 

 indications that the arrival of a new physi- 

 cal truth was near, a truth which was not 

 esplicitlj' stated in Newton's dynamics and 

 which to be fully appreciated hj the human 

 mind needed a new physical concept there, 

 the concept of energy. . The age which saw 

 the arrival of the Undulatory Theory of 

 Light and of the Principle of Conservation 

 of Energy was worthy of the honor of being 

 the age in which Faradaj^ lived. 



Faraday's kesearches. 



When Faraday entered the field of elec- 

 trical research, that which he found there 

 worthy of the name of an exact science 

 were Coulomb's, Cavendish's and Ampere's 

 laws of force of inverse square. The 

 method of analyzing electric and magnetic 

 phenomena which prevailed at that time is 

 well illustrated in Poisson's theory of in- 

 duced magnetism, " who," and here I quote 

 Maxwell, " by following the path pointed 

 out by Newton and making the forces which 

 act between bodies the principal object of 

 study, founded the mathematical theories 

 of electric and magnetic forces." 



The field of Electrical Science, view it as 

 you may, was narrow when Faraday en- 

 tered it. Besides, the old superstition of 

 direct action at a distance surrounded it on 

 every side like a Chinese wall. There 

 seemed to be no exit, no communication 

 with the outside world of science where 

 Faraday saw wide fields of activity opened 



