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The Dutch collection

Geissler rotators
Fun with tubes

   These are fine pieces of artwork and early technique, they were used as
   demonstration apparatus in physics lessons and some times even sold as
   educational physics toys in a box together with a Grenet battery, Most of them
   were used at the end of the 19th century. These motors were sold by
   companies like Max Kohl, Leybolds Nachfolger, Pericaud and Radiguet.
   It must have been a fantastic light show those days, electrical motors where
   just like the Geissler tubes a new phenomena. There were several motor
   designs, in most cases Froment or Wheatstone models.
   Most of this motor designs make use of a soft iron circular core, within this
   core spins a set of coils. There are 4 and 6 pole models mostly with a tapered
   core. On the wooden base are the connections for the motor coil and for the
   high tension. A Ruhmkorff coil or static machine together with sufficient power
   for the motor, often Grenet cells were used, completes the setup.

The look of a fast spinning Geissler tube.
Look here at YouTube for another working example!

close up of the
breaker system

This model is slightly different than the
common Wheatstone models. It has an
iron stem and the poles are not tapered.
The height is about 20 centimeter.
Probably a French model.

Collection of rotators from an old french Pericaud catalog.
(picture courtesy of Alastair Wright)

A Pericaud Geissler rotator
This is the most common model Geissler motor with an height of 21 cm. This model is displayed in the Pericaud catalogue from the early 20th century below.