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 gathering 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 during 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. |
By 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 sufficient 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 abundant 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 furnace the temperature produced by the electric arc; a few centimetres beneath, the crucible containing the matter to be experimented 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
