244 Messi-s. F. C. Calvert and R. Johnson on Alloys. 



of potash, containing as much potassium as exists in the bitar- 

 trate used in the previous experiments, or — 



336 of iron, 



552 of pure carbonate of potash, 



but no results were obtained. 



Alloys of Iron and Aluminium. 



We were induced to make a great many experiments to pro- 

 duce these new alloys, in consequence of the remarkable properties 

 which aluminium possesses, as discovered by M. St. Clair Deville; 

 and what increased oui" desire was, that we hoped they would 

 not only present useful properties, but might be the means 

 of obtaining aluminium cheaper than by the process already 

 discovered. 



We shall not describe all the fruitless essays wc made, but 

 shall confine our observations only to those which gave us satis- 

 factory results. 



The first alloy of aluminium and iron was obtained by heating 

 to a white heat, for two hours, the following mixture : — 



8 equivalents of chloride of aluminium . 1076 

 40 equivalents of fine iron filings . . . 11 20*0 

 8 equivalents of lime 224*0 



The lime was added to the mixture with the view of removing 

 the chlorine from the chloride of aluminium, so as to liberate 

 the metal aluminium ; by forming a fusible chloride of calcium, 

 and subtracting the lime from the above proportions, we ought 

 to have obtained an alloy having the composition of — 



1 equivalent of aluminium . . 14 = 9*09 

 5 equivalents of iron . , . . 140 = 90'91 



l54 = 100-00 



whilst the alloy which we found at the bottom of the crucible 

 was composed of 100 parts as follows : — 



Aluminium .... 12'00 

 Iron 8800 



100-00 

 which leads to the following formula : — 



1 equivalent of aluminium . 11*11 

 4 equivalents of iron . . . 88-89 



100-00 



This alloy, as it will be remarked, has the same composition 

 as one of those of potassium and iron, and, like it, it was ex- 



