John Ayrton Paris, an English doctor, invents and produces a commercial version of his Thaumatrope, in which two images on either side of a disc of card threaded with string appear to merge when spun quickly.
Design for a gas-light night telegraph is published in Mechanics' Magazine. Combinations of six lamps arranged in a triangle represent letters of the alphabet. The lamps are turned on and off by means of a set of taps controlling the flow of mains gas, which is ignited by a small constant pilot light in each lamp. The idea is not known to have been implemented.