LE MONNIER'' S CIRCUIT. 531 



as efficacious^ for the purpose of starting, to challenge an 

 existing theory as to propound a new one. Thus did Le 

 Monnier. Dufay had stated in substance that conductors 

 cannot be electrified unless supported on non-conductors. 

 The Ley den jar, says L,e Monnier, 1 must be an exception 

 to Dufay' s principle, for it can be electrified, although it 

 is supported on the hand, which is a conductor. That 

 shows us, at once, that L,e Monnier and he probably re- 

 flected the idea of the French philosophers generally sim- 

 ply considered the jar as an electrified mass, regardless of its 

 diverse materials. For him the objective point is less the 

 jar, than the circuit. He states the principle of it: "All 

 bodies are electrified by means of a vial of water fitted to 

 a wire," if "placed in any curved line connecting the ex- 

 terior wire and that part of the bottle which is below the 

 surface of the water " but passes at once to something re- 

 markable. Hitherto everything to be electrified was in- 

 sulated on pitch cakes or silk supports. What astonishes 

 L,e Monnier now is, if 200 men be placed hand in hand 

 the end individuals touching the inserted wire and the 

 bottom of the bottle respectively a violent concussion is 

 felt by all at once; and this equally well, whether they are 

 all mounted on cakes of resin or stand on the floor; equally 

 well when they are connected by iron chains; equally well 

 whether the chains dip in the water or lie on the ground, 

 and the electricity runs equally well now he abolishes the 

 men through a wire a league long, "though a part of it 

 dragged on the wet grass, went over channel hedge or 

 palisades and over ground newly ploughed up." He even 

 bends a bar of iron to touch the two points of the jar, and 

 observes that it does not acquire more electricity when 

 held by silk lines than when supported in the hand. 

 Strange, he thinks, how "the electricity will stay in the 

 path thus made for it, without either running off or be- 

 coming absorbed." 



1 Phil. Trans., No. 481, p. 247, 290. Memoirs de 1'Acad. Roy. des Sci., 

 1746. 



