10 HISTORY OF ELECTRICITY. 



restoration of the equilibrium, when the outside 

 and inside are brought into communication sud- 

 denly. But in order to complete this discovery, it 

 remained to be shown that the electric matter was 

 collected entirely at the surface of the glass, and 

 that the opposite electricities on the two opposite 

 sides of the glass were accumulated by their mutual 

 attraction. Monnier the younger discovered that 

 the electricity which bodies can receive, depends 

 upon their surface rather than their mass, and 

 Franklin 12 soon found that "the whole force of the 

 bottle, and power of giving a shock, is in the glass 

 itself." This they proved by decanting the water 

 out of an electrized into another bottle, when it 

 appeared that the second bottle did not become 

 electric, but the first remained so. Thus it was 

 found "that the non-electrics, in contact with the 

 glass, served only to unite the force of the several 

 parts." 



So far as the effect of the coating of the Leyden 

 phial is concerned, this was satisfactory and com- 

 plete : but Franklin was not equally successful in 

 tracing the action of the electric matter upon itself, 

 in virtue of which it is accumulated in the phial ; 

 indeed, he appears to have ascribed the effect to 

 some property of the glass. The mode of describing 

 this action varied, accordingly as two electric fluids 

 were supposed, (with Dufay,) or one, which was the 

 view taken by Franklin. On this latter supposition 



12 Letter *, iv. Sect. 16. 



