Yablochkov candle. Artwork showing the interior workings of a Yablochkov candle, also known as an electric candle. At left is an electrode, which consists of two rods of carbon separated by an inert material. At the top the two rods are joined together by a fuse. When a electric current is applied to the rods the fuse blows, igniting the gas in the lamp. As the gas continues to burn it consumes the electrodes. Lamps often had more than one set of electrodes (as seen in the example at right). One disadvantage of these lamps was that the electrode had to be replaced after each use. Artwork from \Grands Hommes et Grands Faits de l'Industrie\" circa 1880."