206 



MESSRS. C. T. HEYCOCK AND F. H. NEVILLE 



we 



fOSS 



to- 



Curve 3 (upper) and Curve 4 (lower). 



Curve 1. 



\ 



Curve 6. 



Curve 5. 



DESCRIPTION OF THE CURVES. 



Curve 1 is a diagram on a small scale of the whole freezing point-curve. It is intended especially as a 

 key to the larger figures which give special parts, but it also affords an idea of the relative magnitude of 

 the various branches of the curve. 



Curve 2 gives the part of the curve lying between 17 and 44 atoms of aluminium. Experimental points 

 are marked on it by dote, and a continuous line is drawn through the first or upper freezing point of each 

 alloy. This line is what we conceive to be the equilibrium curve. 



Curves 3 and 4 give on the same scale the summit of the curve near AuAl 2 , Curve 4 being the most 

 correct. For the points in Curve 4 both the gold and the aluminium were determined ; the pyrometer was 

 in good order. 



Curve 5 gives the shape of the curve close to the aluminium end, and Curve 6 that close to the gold end. 



The numbers placed above the line of the curve are atomic percentages of aluminium, those below the 

 line of the curve are degrees Centigrade. In Curve 5 the numbers plotted are those of the table 

 diminished by 0'7, to reduce them to our standard value for the freezing point of aluminium, 654-5". 



