Leyden Jars
Procure as much metal foil as possible, either by raiding the nursery or by purchasing some tinfoil-wrapped butter scotch at the confectioner’s, and gum it round the jam jars so as to extend about half-way up the outside (A, [Fig. 3]).
Next solder stiff brass wires (8 inches long) to two round pieces of metal, so cut as to pass the jar mouths readily. To the other end of one brass rod solder another disc of metal, tin—or, better, brass—nicely smoothed along its two edges by sandpaper. The other brass rod may be looped at its end and have tinfoil wrapped round until a respectable knob be formed, or else have a brass bedstead globe soldered on.
Fig. 4.—The electroscope.
These brass standards are then stood inside, with their metal bases resting on the bottom of the jars and surrounded by lead shot to the same height as that of the tinfoil, without. The finished article should appear something like the sketch shown as [Fig. 3].