Demonstration of Michael Faraday’s lines of force

A silent excerpt from an educational film describing Michael Faraday’s discovery of lines of force.

Made by Kodak, the ‘cine-Kodagraph’ film describes how lines map out the direction and strength of an electric field around a magnet. The force upon an electrified particle is in the direction of the lines. The force is greatest when the lines are most closely crowded.

The film uses illustrations to show the distribution of lines of force when two conducting spheres, with equal opposing charges, approach and recede.

The film ends by showing how the demonstration was made and filmed, using a controllable moving camera projecting onto a static board illustrated with the lines of force. The film shows a young Lawrence Bragg undertaking the demonstration, possibly in advance of his 1934 Royal Institution Christmas Lectures on ‘Electricity’.

For this film, and several others in our collection, we have tried to contact any known copyright holders and believe it to be an orphan work. If you are the rights holder, would like it to be taken down, or have any more information, please get in touch at

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