Provide two small balls of equal size; both made of gum-lac, and cover
one with gold leaf. Suspend these balls from a beam by fine white
silk threads, at a little distance from each other, so as to allow a
comparison of their motions. Then rub a stick of red sealing-wax upon
any woollen substance, or warm it at the fire, and present it to the
balls; when it will be at once seen that the gilt ball, which readily
admits of the transfer of electricity from one side to the other, will
be sooner and more powerfully attracted than the other ball, which
allows of no motion in its electricity. The latter ball will, however,
by slow degrees be feebly attracted, and may, at length, be made to
adhere for a considerable time to the sealing-wax.