MODERN USES OF THE METAL 

 ALUMINIUM 



By RICHARD SELIGMAN, Ph.D. 



Aluminium, which is the chief component of all clays and an 

 important constituent of many rocks, is one of the most widely 

 distributed chemical elements. Despite this fact, it was not 

 isolated until the year 1827, when Wohler obtained the metal in 

 the form of minute grey scales by the interaction of aluminium 

 chloride and metallic potassium. Although this method was 

 improved upon by St. Clair Deville, aluminium did not become 

 a common metal until the simultaneous discoveries of Heroult 

 and Hall in 1887-8 permitted of its manufacture by electrolysis. 

 The process perfected by these two inventors, which is the only 

 one in use to-day, consists in electrolysing a solution of alumina 

 in the molten double fluoride of aluminium and sodium known as 

 cryolite. The electrodes used are made of carbon and the pro- 

 ducts of electrolysis are aluminium on the one hand and oxygen 

 and the oxides of carbon on the other. The electrolysis is carried 

 on at a temperature of 950-1000 C, so that the metal, which 

 melts at 657 C, is obtained in the molten form. 



For close on ten years after these discoveries, aluminium was 

 still regarded as little more than a scientific curiosity but more 

 recently it has found its way into a rapidly increasing number of 

 industries, for many of which it has become an essential. 



The rapid development of the aluminium industry is an 

 exemplification of the rule which, though universal, is frequently 

 unrecognised — that supply creates demand. To show that the 

 advance is in this case governed by this rule, it will be necessary 

 to consider the uses to which the metal has been put during the 

 last seven years. At the beginning of the period (1904-5), owing 

 to the perfection of electrical methods of manufacture, aluminium 

 had been available in large quantities for close on fifteen years 

 but the world's output was only about 9,000 tons and the price 

 £107 per ton ; the amount produced was undoubtedly in excess 



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