42 Electric and Magnetic Science 



o 



Shortly after the discovery of the Leyden phial, as it was 

 named by Nollet, had become known in England, a London 

 apothecary named William Watson (6. 1715, d. 1787)* noticed 

 that when the experiment is performed in this fashion the 

 observer feels the shock " in no other parts of his body but his 

 arms and breast " ; whence he inferred that in the act of 

 discharge there is a transference of something which takes the 

 shortest or best- conducting path between the gun-barrel and 

 the phial. This idea of transference seemed to him to bear 

 some similarity to Nollet's doctrine of afflux and efflux; and 

 there can indeed be little doubt that the Abbe's hypothesis, 

 though totally false in itself, furnished some of the ideas from 

 which Watson, with the guidance of experiment, constructed 

 a correct theory. In a memoiirt)read to the Eoyal Society 

 in October, 1746, he propounded the doctrine that electrical 

 actions are due to the presence of an " electrical aether/' which 

 in the charging or discharging of a Leyden jar is transferred, but 

 is not created or destroyed. The excitation of an electric, 

 according to this view, consists not in the evoking of anything 

 from within the electric itself without compensation, but in the 

 accumulation of a surplus of electrical aether by the electric at 

 the expense of some other body, whose stock is accordingly 

 depleted. All bodies were supposed to possess a certain natural 

 store, which could be drawn upon for this purpose. 



" I have shewn," wrote Watson, " that electricity is the 

 effect of a very subtil and elastic fluid, occupying all bodies in 

 contact with the terraqueous globe ; and that every-where, in 

 its natural state, it is of the same degree of density ; and that 

 glass and other bodies, which we denominate electrics per se y . 

 have the power, by certain known operations, of taking this fluid 

 from one body, and conveying it to another, in a quantity 

 sufficient to be obvious to all our senses; and that, under 



* Watson afterwards rose to eminence in the medical profession, and was 

 knighted. 



t Phil. Trans, xliv., p. 718. It may here he noted that it was Watson who 

 improved the phial by coating it nearly to the top, both inside and outside, with 

 tinfoil. 



