3. The condenser electrometer
Volta later adapted the apparatus, by connecting it directly to an electrometer. First he did it rather strangely: he screwed a metal plate onto the knob of the electrometer, using his hand as the second plate and insulating it in a sort of half glove made of waxed or varnished taffeta.
Only towards 1799, when completing his studies into the electromotive power of bimetal contacts, did Volta describe the electroscopic condenser in the form we find in physics textbooks: “On top of one of the usual bottle-shaped electrometers… I screw a plate thinly covered with resin. To have a really good condenser, this is then covered by another bare plate, which touches it all over and which has a convenient handle for lifting and replacing.

Condenser electrometer

Volta's original sketch of the condenser electrometer