OF SILVER BETWEEN ZINC AND LEAD. 



11 



position of the heavier liquid phase, whieh is in equilibrium 

 with the lighter liquid phase and solid zinc. BG is the curve 

 of solubility of solid zinc in 

 lead, and the curve CDE ^ 

 shows the mutual solubilitv 

 of liquid zinc and lead in 

 eacli other. The curve CDE 

 and a point on the curve 

 BC have been determined 

 by Spring and Romanoff,^^ 

 but their results agree nei- 

 ther with the determinations 

 of Wright and Thompson 

 nor with my own, nor with 

 the experience of practical 

 metallurgists. I prefer 

 therefore to rely on the data 

 of Wright and Thompson 

 and my own, though they 

 are rather meagre. From 



these it appears that the curve CD proceeds upwards nearly 

 perpendicularly and by extrapolation the composition of the 

 point C is estimated at 1.2 percent zinc, the temperature being 

 that of the eutectic point E^ which is only slightly below 420° 

 the melting point of pure zinc. Working at the temperature 

 of boiling mercury, that is about 358°, and employing the ap- 



1) Zeits. anorg. Chem., 13, (1897), 29-35. That they Jiave taken the liquid phases a 

 such, and not the solidified layers is much in their favour ; but they did not wait long 

 enough before taking the samples for analysis. At lower temperatures the separation of the 

 two layers may have been incomplete, and so vitiated their results. 



