THE ELECTRIC FURNACE IN CHEMISTRY. 4.17* 



fice, leaving the constructive part to the master-builder, from 

 whom has descended the professional architect. 



Chiefly for form's sake reference must be made to the gath- 

 ering together and consolidation which, in our times, has been 

 set up in the architect's profession. There is little to remark 

 further than that the members of it, having been but few dur- 

 ing earlier periods, when the amount of architectural building 

 was relatively small, segregation and association of them could 

 scarcely occur. Recently, however, there has been formed an 

 Institute of Architects, and the body of men devoted to the art 

 is tending more and more to make itself definite by imposing 

 tests of qualification. 



At the same time cultivation of the art and maintenance of 

 the interests of those pursuing it are achieved by sundry special 

 periodicals. 



THE ELECTRIC FURNACE IN" CHEMISTRY. 



Br M. H. MOISSAN. 



THE reverberatory electrical furnace with movable electrodes, 

 which we devised in 1802, and in which we have made many 

 improvements, is very simple in construction, has been of great 

 service, and has permitted us to deal with problems which have 

 been hitherto insoluble. By means of this apparatus we have 

 been permitted, by obtaining a sufiicient temperature, to produce 

 the diamond, to crystallize metallic oxides, to reduce those which 

 have hitherto been refractory, to melt metals heretofore infusible, 

 to distil lime, silica, zirconia, and carbon, and to cause an abun- 

 dant volatilization of such metals as platinum, copper, gold, iron, 

 manganese, aluminum, and uranium. Some bodies that could 

 not be brought to a condition of fusion, like magnesia, uranium, 

 tungsten, and molybdenum, could be made to assume the gaseous 

 state in the electric furnace. In our studies we have frequently 

 dealt with the vapor of lime and silica. 



When using the currents of machines of from one hundred 

 to three hundred horse power, we have in the midst of the fur- 

 nace the temperature produced by the electric arc ; a few centi- 

 metres beneath, the crucible containing the matter to be experi- 

 mented upon; and at the bottom, a mass of quick-lime in full 

 ebullition. The imperfect conducting power of this substance is 

 a fortunate quality for us. It isolates the heat which the electric 

 arc can furnish into the smallest possible cavity. 



This new apparatus permits us to approach the study of a 

 whole series of simple bodies which have been till now mere 



VOL. XLVIII. 29 



