1889.] en Aluminium, 463 



it required that the aluminium used should be of good quality, but 

 also that the copper must be of the very best obtainable. For this 

 purpose only the best brands of Lake Superior copper should be used. 

 Inferior brands of copper or any impurities in the alloy give 

 poor results. The alloys all possess a good colour, polish well, keep 

 their colour far better than all other copper alloys, are extremely 

 malleable and ductile, can be worked either hot or cold, easily 

 engraved, the higher grades have an elasticity exceeding steel, are 

 easily cast into complicated objects, do not lose in remelting, and are 

 possessed of great strength, dependent, of course, on the purity and 

 percentage of contained aluminium. The 10 per cent, alloy, when 

 cast, has a tensile strength of between 70,000 and 80,000 lbs. per 

 square inch, but when hammered or worked, the test exceeds 

 100,000 lbs. (A sample shown broke at 105,000 lbs.). 



An attempt to enumerate either the present uses or the possible 

 future commercial value of these alloys is beyond my present purpose. 

 I may, however, remark that they are not only adapted to take the 

 place of bronze, brass, and steel, but they so far sui-pass all of those 

 metals, both physically and chemically, as to make their extended 

 use assured. (Sheets, rods, tubes, wire, and ingots shown.) 



But even a more important uso of aluminium seems to be its em- 

 ployment in the iron industry, of which it promises shortly to become 

 a valuable factor, owing to certain effects which it produces when 

 present, even in the most minute proportions. Experiments are now 

 being carried on at numerous iron and steelworks, in England, on the 

 Continent, and in America. The results so far attained are greatly 

 at variance, for whilst in the majority of cases the improvements 

 made have encouraged the continuance of the trials, in others the 

 result has not been satisfactory. On this point I would wish to say 

 to those who may contemplate making use of aluminium in this 

 direction, that it would be advisable before trying their experiments 

 to ascertain whether the aluminium alloy they may purchase actually 

 contains any aluminium at all, for some of the so-called aluminium 

 alloys contain little or no aluminium, and this may doubtless 

 account for the negative results obtained. Again, others contain such 

 varying proportions of carbon, silicon, and other impurities, as to 

 render their use highly objectionable. 



It seems to be a prevailing idea with some people, that because 

 aluminium is so light compared with iron, that they cannot be directly 

 alloyed, and furthermore, that for the same reason, alloys made by 

 the direct melting together of the two metals would not be equal to 

 an alloy where both metals are reduced together. Now, of course, 

 this is not the case, and the statement has been put forward by those 

 who were only able to make the alloys in one way. 



Aluminium added to molten iron and steel lowers their melting 

 points, consequently increases the fluidity of the metal, and causes it 

 to run easily into moulds and set there, without entrapping air and 

 other gases, which serve to form blow-holes and similar imper- 



