238 ANNUAL EEPOET SMITHSONIAN INSTITUTION, 1912. 



rious Foucault currents are reduced to a minimum. The manu- 

 facture of transformers has therefore become much cheaper, for the 

 proportion between iron and copper is much more economical. The 

 production of this silicon iron alloy, \vith its very low percentage of 

 carbon, and that of the chrome nickel steels, almost free from carbon, 

 became possible only after silicon and chrome, entirely free from 

 carbon, could be manufactured by electric smeltmg processes. 



Electro-steel. — Since the electric smelting furnace has come into 

 use in the steel mdustry the problem of removing sulphur, which 

 engaged the attention of chemists for so many years, has been solved. 

 It has been found that the electric furnace process produces a slag 

 free from metal, and such a slag is the prime requisite for the com- 

 plete desulphuring of the steel bath. 



Electrolytic iron. — Superior to the silicon steel, poor in carbon, 

 in its electric properties is the "Ideal" metal for electromagnets 

 — the pm'e electrolytic iron — first produced by Franz Fischer, of 

 Charlottenburg, and now manufactured by the firm Langbein- 

 Pfanhauser & Co., Leipzig. Formerly it was impossible to produce 

 it free fiom hydrogen, consequently it was hard and brittle and was 

 not malleable. Only by electrolyzing at 100° to 120° C. and em- 

 ploying an iron salt solution mixed with hygroscopic salts, such as 

 calcium chloride, the iron became free from hydrogen. Its hard- 

 ness then sinks far below that of silver and gold and is not much 

 greater than that of aluminium. It possesses the valuable property 

 of becoming magnetic more quickly than ordinary iron, containing 

 carbon or siiicoft, and also of again losing its magnetism more readily, 

 thus considerably increasing the efficiency of electromotors, for 

 which it is used. Amongst the exhibits you will find several objects 

 made of this electrolytic iron; for example, a cathode made from 

 an electrolytic iron plate during five days of uninterrupted opera- 

 tion; also plates made by rolling; fm'ther a motor which, if con- 

 structed of silicon iron, would furnish 0.5 horsepower, but being 

 composed of electrolytic iron, though in use lor several months 

 without appreciable signs of wear, it now furnishes 1.3 horsepower, 

 in other words, it is two and one-half times as efficient.^ 



With all these now materials at our disposal, among which I 

 must also mention copper, with 10 per cent silicon, and copper 

 nickel, we shall surely be able to improve all sorts of chemical ap- 

 paratus that suffer so much from wear and tear. 



After this short invasion of the domain of metallurgy, we shall 

 now turn our attention to the chemical industry proper, first deal- 

 ing with the manufacture of inorganic substances, the heavy 

 chemicals. 



« See Zeitschrift fiir Electrochemie, No. 16, 1909. 



