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X 
ner defcribed by Dr. franklin. If the balls are 
taken off from the wires of the bottle ; the wires 
being pointed, and one of them placed before the 
globe; or a prime-conduCtor, ekCtrified pojitively: 
the phenomena of charging the Leyden bottle will 
be difcovered by the different appearances, at the 
end of the wires ; as at tab. xiv. fig. 4. If the bottle 
be thus placed before a conductor, eleCtrified nega- 
tively, or the infulated rubber to a machine; the 
appearances, at the ends of the wires, will be re- 
verted : as upon Dr. franklin’s principles they 
ought to be; and thus explain his theory of the 
Leyden phial. 
But a more fimple, and beautiful analyfis of the 
Leyden phial, hath not, I think, yet been exhi- 
bited ; than the following. Let a bottle that will 
hold near a pint; having a long neck (about an 
inch in diameter,) befurmfhed with a fmall plate at 
the top; with a valve properly fecured, after the 
bottle is exhaufted : from which plate, a wire 
about one eighth of an inch in diameter, is to 
projeCt a little below the neck ; and terminate with 
a blunt end. The top is to be covered with a 
round brafs cap, firmly fixed thereon ; and made 
air-tight. The bottom of the bottle fliould be 
coated with tin-foil, which fhould be continued 
three inches up the fide. This bottle will charge and 
difcharge feveral times in a minute ; and the tin- 
foil coating, will prevent the fhock from affeCling 
the hand of the operator ( c h The phenomena of 
charging the Leyden bottle, is elegantly explained 
by this contrivance ; and is made vifible, by the 
end of the wire ; on which, the appearances vary, 
according as the bottle is charged, viz. pofitively, 
(c-) The bottle being held below the edge of the coating. 
or 
