Thomson-Houston dynamo. 19th-century artwork of the bipolar dynamo (producing 20 to 90 kilowatts of power) and electric generator manufactured by the Thomson-Houston Electric Company. This company was founded in the USA in 1883. It produced a range of electrical goods. Dynamos are devices used to convert rotary motion into electrical power. This is achieved by rotating magnets around wires, and generates direct electrical currents. Artwork from the first volume (1897) of 'La Revue Scientifique et Industrielle' by French chemist and inventor Jules-Louis Breton (1872-1940).