[ I0 9 ] 
of an Inch at Top, with Leaf-Brafs. As much of 
the internal Surface as was covered amounted to 
1 1 2 c> fquare Inches. But the Difficulty I met with 
in procuring this Glafs was lufficiently recompenfed 
by the great Increafe of the Explofion therefrom, 
when fully electrifed, and difeharged in the fame 
manner as the glafs Jar before-mention’d. The 
Report was vaflly louder j all the attendant Phano - 
mena greatly exceeded any thing of this kind I was 
before acquainted with. As the Quantity of Metal 
within this Jar did not exceed two Drams, this Ex- 
periment gives further Weight to my Opinion be- 
fore-mention’d § XIV. in relation to the manner of 
increaftng the Effects ot the Experiment of Leyden ; 
and from what the Phenomena of that furpriftng 
Experiment principally proceed ; viz* not from the 
Volume of the prime Conductor, nor from the 
Quantity of non electrical Matter contained in the 
Glafs, but from the Number of Points of non-elec- 
trical Contact both within and withoutfide of the 
Glafs, and from the * Denftty of the Matter confti- 
tuting thofe Points. 
' (JXVII. It mud be obferved, that, exteris paribus, 
the electrical Explofion is greater from hot Water 
included in Giaffes than from cold 5 and from thefe 
glafs Jars warmed than when they are cold. 
§ XVII. 
* Though the Denfity of the Matter conftituting thefe Points 
proceeds from their Number in a mathematical Senfe, yet in a po- 
pular one I take the Liberty to diftinguifh them. 
