Littell's Living Age/Volume 135/Issue 1740/The Electric Candle
Experiments have been recently conducted at the West India Docks with the view of testing the illuminating power of the so-called electric candle devised by M. Paul Jablochkoff. This simple means of producing a steady electric light consists in placing two carbon pencils side by side, but separated by a bar of a composition called "kaolin." On the passage of the current the carbons slowly burn down, and the kaolin is consumed by the heat at exactly the same rate. The carbons are thus kept always at the same distance apart, and the light playing between them is thus rendered constant without the aid of complex regulators. In the experiments at the West India Docks the current was produced by a magneto-electric machine, worked by a small steam-engine, and the results are described as having been eminently satisfactory. For lights of small and medium size, an apparatus of even greater simplicity may be employed, the carbon points being dispensed with and nothing used beyond a piece of the so-called kaolin held between the electrodes. But M. Jablochkoff's prime improvement, which promises to greatly extend the use of the electric light, consists in his ability to divide the current, so as to supply several candles placed in the same circuit, each with its own coil. These candles may be of various degrees of illuminating power, and may be lighted or extinguished separately. In short, the electricity appears to be under such control, that it might be generated in some central establishment and laid on through wires to the several centres of illumination, just as freely as gas is at present distributed through pipes to any number of burners. MM. Denayrouze and Jablochkoff, who have employed the light in Paris, have described their process before the French Academy of Sciences.