Hippolyte Pixii (1808–1835) was an instrument maker from Paris, France. In 1832 he built an early form of alternating current electrical generator, based on the principle of magnetic induction discovered by Michael Faraday. Pixii's device was a spinning magnet, operated by a hand crank, where the North and South poles passed over a coil with an iron core. A current pulse was experienced each time a pole passed over the coil. He also found that the current direction changed when the North Pole passed over the coil after the South pole. Later on acting on a suggestion by André-Marie Ampère other results were obtained by introducing a commutator, which produced a pulsating direct current which at this time was preferable to alternating current. Although Pixii at the time did not fully understand electromagnetic induction, his device led to more sophisticated devices.