Design
A Yablochkov candle consists of a sandwich of two long carbon blocks, approximately 6 by 12 millimetres in cross-section, separated by a block of inert material such as plaster of paris or kaolin. There is a small piece of fuse wire or carbon paste linking the two carbon blocks at the top end. The assembly is mounted vertically into a suitable insulated holder.
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. The first candles were powered by a Gramme machine.
On disconnecting the supply, the arc extinguishes. It cannot be restarted, as there is now no fuse wire between the electrodes. Once switched off or consumed, the candle must be replaced. Electrodes last about two hours.
The advantage of the design over other carbon arc designs is that it removes the need for a mechanical regulator to maintain the appropriate distance between the carbon blocks to sustain the arc.
Read more about this topic: Yablochkov Candle
Famous quotes containing the word design:
“We find that Good and Evil happen alike to all Men on this Side of the Grave; and as the principle Design of Tragedy is to raise Commiseration and Terror in the Minds of the Audience, we shall defeat this great End, if we always make Virtue and Innocence happy and successful.”
—Joseph Addison (16721719)
“If I knew for a certainty that a man was coming to my house with the conscious design of doing me good, I should run for my life ... for fear that I should get some of his good done to me,some of its virus mingled with my blood.”
—Henry David Thoreau (18171862)