ELECTRICITY AT THE WORLD'S FAIR. 45 



of the conditions under which we expect to see heat generated is 

 the apparatus to be seen in this exhibit which may be appropri- 

 ately termed the " water-pail forge/' This consists of an ordinary 

 wooden pail filled with water into which dips a metal plate con- 

 nected with one terminal of the electric circuit. The other termi- 

 nal is attached to a pair of blacksmith's tongs, with which the op- 

 erator picks up and holds the piece of metal to be heated. Imme- 

 diately upon his plunging this into the water the liquid begins to 

 sputter and the metal to glow, until in a few seconds it is brought 

 to a welding heat and is then speedily melted. The heating is 

 so rapid that neither the water nor the metal a few inches away 

 are more than slightly warmed. This curious phenomenon appears 

 to be due to the localization of the resistance of the circuit at the 

 surface of the heated metal by the interposition of a layer of hy- 

 drogen between the metal and the liquid. This is the explanation 

 offered by two Belgian engineers who recently brought out the 

 process abroad with apparently no knowledge of its prior use in 

 this country. In their apparatus they used a glass jar lined with 

 lead which formed the positive pole. The water was acidulated 

 to render it conducting. When the circuit is completed by the 

 immersion of the metal to be heated the current decomposes the 

 liquid, the oxygen going to the lead plate and the hydrogen to the 

 iron or other immersed metal and preventing any direct contact 

 of the metal and the liquid. As hydrogen is a very poor conductor 

 of electricity, the resistance would then be localized at the surface 

 of the metal plate, with the result of heat being rapidly developed 

 at this point. An American investigator, Mr. Jules Neher, who 

 has experimented with the process, regards the heating as being 

 due to the formation of an arc between the heated metal and the 

 liquid, as he has observed that the heating does not take place if 

 the metal be immersed before the current is turned on, the energy 

 of the current then being spent in the electrolysis of the liquid. 

 His explanation is that immediately the metal touches the liquid 

 hydrogen begins to be liberated and, interposing itself between 

 the metal and the liquid, draws an arc in the act of pushing the 

 two asunder. This arc formed under water quickly raises the 

 metal to a high temperature. Whatever the precise explanation, 

 it certainly is a most astonishing thing to see pieces of iron and 

 steel glowing at a white heat and running away in melted glob- 

 ules while surrounded by water. The capabilities of the appara- 

 tus would appear to be almost unlimited, and it is not too much 

 to say that it is destined to find wide application in the arts. The 

 operator has at his command the practically unlimited energy of 

 electricity, and should be able to reach temperatures with it here- 

 tofore unattainable. The Belgian experimenters are reported to 

 have succeeded in fusing carbon, and it has been suggested that 



