Pair of insulated stools

Pair of glass insulated four-legged stools.

Early experiments in electrostatics stood upon insulated stools of this type whilst holding a chain or wire communicating with the prime conductor of an electrical machine.

The stool is made of mahogany and has four strong glass legs, one at each corner. Before use, these legs are wiped clean and dry in order to avoid any undesirable conduction. When the electrical machine is set in motion, sparks may be drawn from any part of the person who is standing on the stool. For the time being, this person is part of the prime conductor and is strongly electrified, although feeling no effects themself. This stool appears to have been well used, showing how popular these electrical demonstrations were.