Gramme’s direct current machine (1871)

The electric motor, The history of electricity

It was a Belgian electrician, Zénobe Gramme, who conceived the principle of the dynamoelectric machine – or dynamo – in 1869. The device generates an electric current via the activation of a mechanical crank.

The machine’s functioning hinges on the phenomenon of electromagnetic induction discovered by Faraday: electric coils – windings of conductive wire – are rotated around a magnet. An electric current will then appear in the various coils of the machine; these currents are accumulated by means of a collector and the direct current thus obtained is much more efficient than that of a simple electric battery.

The model depicted in The Spirit of Electricity is the one of 1871, which was presented to the Paris Academy of Sciences and then mass-produced during the 1870s. In 1873 Gramme‘s associate, Hippolyte Fontaine, discovered that the machine was reversible: if it was connected to a current, the crank would turn by itself: this is the principle of the electric motor.

Back to top of page