144 E. F. ROEBER 



expect from future electrochemical developments. The 

 achievements of the past have given us new methods of stor- 

 ing and transmitting energy ; they have enormously cheapened 

 the production of known substances, like aluminum, and have 

 given us new substances of great commercial usefulness. 



In this respect the industrial development of the electric 

 furnace is very instructive. As the pioneers of electric fur- 

 nace work, the two brothers, Eugene H. Cowles and Alfred 

 H. Cowles, have slightly distinguished themselves, especially 

 in the production of aluminum alloys. For the industrial 

 development of the resistance furnace, the highest credit is due 

 to the persevering work of Edward Goodrich Acheson. The 

 extended laboratory researches of the French professor, Mois- 

 san, have thrown much light on the production of carbides. 



The distinction between arc and resistance furnaces is so 

 familiar that it is unnecessary to dwell on it here, nor shall 

 details of design be discussed. But we may record the grad- 

 ual change of the purpose to which the electric furnace is 

 being put in practice. In the early days the intention was 

 to produce as high a temperature as possible, and the result 

 was the foundation of entirely new industries, like those of 

 calcium carbide, carborundum and artificial graphite. For 

 the production of these substances temperatures were re- 

 quired that could not be obtained by any other means but the 

 electric furnace. In more recent years the intention has been 

 rather to design furnaces so as to allow exact regulation of the 

 temperature, and the electric furnace has thus been found 

 suitable for reactions which do not require abnormally high 

 temperatures. 



The effect of regulating exactly the furnace temperature 

 is very instructively shown by the example of treating a mix- 

 ture of silica and carbon, which has been one of Acheson's 

 fields of special research. By changing the conditions (by an 

 appropriate design of the furnace so as to meet the special 

 conditions of each case) it is possible to produce any one of 

 the following substances: Carborundum, ''white stuff," 

 graphite, silicon, siloxicon. 



The abnormal boom of calcium carbide in Europe, which 

 naturally led to overproduction, resulted in various European 



