THE PAST AND FUTURE OF ALUMINUM. 401 



chemically pure aluminum from the crude bauxites and corun- 

 dums of which considerable quantities have been discovered in 

 the northern United States. The factory at Neuhausen utilizes a 

 part of the falls of the Rhine at Schaffhausen for the propulsion 

 of powerful turbines which directly work the dynamos whence 

 electricity is obtained for the production of aluminum and its 

 alloys. Important manufacturing centers have also been estab- 

 lished in England and Germany, and there are some in France. 



By these new methods, which are still susceptible of improve- 

 ment, a considerable saving over the old purely chemical processes 

 is gained in the treatment of the minerals. In either case the 

 chief effective agent is heat, and it is utilized far more completely 

 in the electrical furnaces than in the older furnaces, which were 

 subject to many cooling influences. Not more than four hundred 

 grammes of coal burned in the furnace of a steam engine driving 

 a dynamo will produce electrical energy sufficient to isolate in 

 a molten electrolyte one kilogramme of aluminum. More than 

 twenty times as much would have been required in the old chem- 

 ical process. By virtue of this better utilization of heat, with 

 greater profection in the equipment and management of the 

 shops, the price of aluminum has continued to decline, till it is 

 now very near the point when the metal can be profitably applied 

 to the fabrication of many articles. 



The alloys of aluminum now occupy a high position in practi- 

 cal industry. Aluminum bronzes and platings, lighter and more 

 tenacious and more resisting than copper, and conducting heat 

 and electricity better, will take its place. The new shops are also 

 working for the production of cast and malleable iron, and they 

 are in request by smiths for refining cast iron and steel. 



The metallurgy of iron is now an exact science as well as an 

 industry. Informed by analysis of the exact composition of the 

 elements that enter into the fusion-bed, and of the character of 

 the products at each moment of the operation, the metallurgist 

 can determine with accuracy what be must eliminate and what 

 add to give his product the quality required for the use to which 

 it is to be put. A few hundredths of alloy will decide what it 

 shall be. A little chromium will render artillery projectiles proof 

 against breaking ; nickel increases the resisting power of sheath- 

 ings. Introduced at the right time into the Bessemer converter 

 or the Martin furnace, a small proportion of the alloy of iron and 

 aluminum communicates to the melted metal a fluidity which 

 facilitates the disengagement of the gases that would otherwise 

 remain imprisoned in the metallic bath, producing blow-holes, 

 and destroying homogeneity and resistance in large pieces. 



New uses are constantly found for the pure metal ; less em- 

 ployed in jewelry, it is more used in the modest ranks of plated 



VOL. XLIV. 31 



