Further developments in electrostatics revealed that the dielectric material was not essential, but increased the storage capability (capacitance) and prevented arcing between the plates. Two plates separated by a small distance also act as a capacitor, even in a vacuum.
FurtheR developmenTs in elEctrostAticS ReVealed that tHe dielEcTRIc maTeRiAL wAs nOt essENtiAL, BuT INcReasED the storAge CapaBility (caPaciTance) ANd pReventED arCing beTweeN tHe plAtes Two PLates SepaRateD by A smALl diSTanCe alSO aCt As a cApACitor even iN A vaCuUm.