154 JAMES CLEKK MAXWELL 



The idea was a bold one : for a youth of twenty- 

 three to explain, by means of tho motions of an 

 incompressible fluid, sonic of the less complicated 

 phenomena of electricity and magnetism, to show how 

 the laws of the attractions of magnets and currents 

 may be clearly conceived without making any as- 

 sumption as to the physical nature of electricity, or 

 adding anything to that which has already been 

 proved by experiment. 



It may be useful to review in ;i very few words 

 the position of electrical theory* in 1S55. 



Coulomb's experiments had established tho funda- 

 mental facts of electrostatic attraction and repulsion, 

 and Coulomb himself, nlnuit 17S5, had stated a theory 

 based on these experiments which rould "only bo 

 attacked by proving his experimental results to bo 

 inaccurate, "f 



Coulomb supposes tho existence of two electric 

 fluids, the theory developed previously by Franklin, 

 but says 



" Jc previous i*wr mettre la tlieoiie <|M*i va siiivru :i Tabri 

 tie tutite dispute systeiiuit'uiut', quo dans la >u|po,iti<>n do 

 deux fluides elcctriqwes, j n'ai autru intetitiot) <|irc tie pie.stnUr 

 avec le nioius dV-lcinents possible' los K-sultats du calcul et 

 de I'expdrienee, tt nou d'indiqucr k-;> writ.il ilc.s causes dc 

 Telectricitd." 



Cavendish was working in Kngland about, tho 

 same time its Coulomb, but he published very little, 



* An JiUtorical account of the development of the scienio of 

 tlecliicity will bi? found in tlie aiticlo * KItctricity " in the Lnrydo- 

 j,'<fiti<i Jti-ilMHirn 9 ninth ulition, by l'iofi-M:>'r Cbry.stal. 



t ThoinMiti (I^urd Kfl\in ; , * Tapera vii KleitniNtatiftf and Mag. 

 net ism/' p. 15. 



