What is "yablochkov candle"

n. A type of electric carbon arc lamp consisting of a sandwich of two long carbon blocks separated by a block of inert material. There is a small piece of fuse wire or carbon paste linking the two carbon blocks at the top end. On application of the electric supply, the fuse wire 'blows' and strikes the arc. The arc then continues to burn, gradually consuming the carbon electrodes (and the intervening plaster) as it does so.

A Yablochkov candle (sometimes electric candle) is a type of electric carbon arc lamp, invented in 1876 by Pavel Yablochkov.