MICHAEL FARADAY 257 



fundamentally important as the researches of Dalton and 

 Gay-Lussac concerning the combining weights and volume 

 of chemical substances, and it further gave the first evidence 

 of the existence of certain fundamental smallest quantities of 

 electricity - the elementary electric charges - of which all 

 larger quantities are composed, just as all material bodies are 

 made up of atoms. 



In the year 1837, Faraday developed the idea of electric 

 lines of force, which represent the total effect of all electric 

 forces, just as the magnetic lines of force do for magnetic 

 forces. The course of the electric lines of force, from one 

 electrified body through space to the other on which the 

 opposite electricity produced by influence is seated, is not 

 so easily visualised as the magnetic lines of force are, at 

 least approximately, by means of iron filings. Faraday 

 studied the course of lines of force experimentally, in the 

 most admirable manner, by following out in detail the phe- 

 nomena of influence, particularly in cases where the effect 

 obviously takes place in curved lines around obstacles. 

 Though this action in curved lines is by no means in contra- 

 diction with Coulomb's law, it is nevertheless usually only 

 predictable in single cases with the greatest mathematical 

 difficulty. 



Faraday's conception of lines of force gives here, as in all 

 other cases, a quick means of orientation, and it also goes 

 beyond Coulomb's law and gives the essential of all electrical 

 force effects, by a geometrical representation of the states of 

 space, otherwise unknown, which condition these effects. It 

 was a fundamental advance for all time, that Faraday here 

 attempted to study the behaviour of nature by observation, 

 from an entirely new standpoint. The gain appeared in its 

 full extent, when thirty years after. Maxwell was able to ex- 

 press Faraday's conception of lines of force, which his contem- 

 poraries had not been able to follow, by means of equations. 



However, Faraday's new point of view of electric force 

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