260 Scientific Intelligence. 
D=spnsa0 Centimeter, 
A=1 centimeter. 
The amount of energy thus calculated is not so great as to afford 
any argument against the conclusion which general knowledge of 
divisibility, electric conductivity, and other properties of matter 
indicates as probable; that, down to thicknesses of xouv0s 0. 
centimeter for the metal plates and intervening spaces, the contact 
electrification, and the attraction due to it, follow with but little if 
Hence, if 
experim 
measurable thickness with measurable intervals between them. 
But let D be a two-hundred-millionth of a centimeter, If the pre- 
ceding formule were applicable to plates and spaces of this degree 
of thinness we should have 
A=1,000,000 centimeters or 10 kilometers, 
probably much more than the whole heat of combination of equal 
masses of zinc and copper melted together. For it is not probable 
that the compound metal when dissolved in an acid would show 
anything approaching to so great a deficiency in the heat evolved 
below that evolved when the metallic constituents are separately 
i he experiment sh 
nergy, a mixture of zinc and copper filings would rush into com- 
bination (as the i aipiied y of gunpowder do) on being heated 
u 
c fa 
centimeter thickness, at a distance of on Yr soy Of a centi- 
meter asunder, must be rae we 3 less than that calculated from the 
i e law of its variation observed for 
