These machines were made by designed by Francis Hauksbee (1666-1713) and made by George Adams, instrument maker to the king. With the machine on the right, the glas globe is held vertically and rotated by means of a handle and gearing mechanism which is in the bras box. A piece of sheepskin was held against the globe and created the charge when the glas was rubbed against it. The globe of the instrument on the right contained a small circular piece of wood with threads attached. These would react by being attracted to the surface of the globe if it was rubbed to develop a static charge.
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