SS4 Mr. G. B. Jerrard on a Method of Transforming Equations 



The slags from this roasting are subjected to another opera- 

 tion. They are fused with a poor and highly sulphurous ore ; 

 the sulphur and iron of the ore combine with a portion of the 

 copper in the slags, and form a rich coarse metal, having an 

 impure alloy as bottoms, termed white metal, a highly crystal* 

 line alloy, the general composition of which is represented by 

 the following analyses : — 



Copper . 

 Tin . . 

 Antimony 

 Iron . . 

 Sulphur 



99-8 100 



This alloy is refined by fusing it with an earthy mineral, com- 



{)Osed principally of protoxide of iron and silica, containing a 

 ittle copper and tin, which produces a compact alloy approaching 

 speculum metal of an average composition of — 



Copper 63 



Tin 27 



Antimony .... 5 )i- 



Iron 4 



Sulphur ..... 1 



Too ^ 



This white metal is used for making buttons and such articles 

 as are cast, and is sold for little more than the value of the 

 copper it contains. Any process that would separate the tin 

 easily from the copper, and make it marketable, would be of 

 importance to the smelter. 



[To be continued.] 



V 



■ ■■■'■ ■ -■" ' ' ' . I ■ 11 



LVIII. On a Method of Transforming Equations by meani of 

 Symmetrid Functions. By G. B. Jerrard*. 



Introduction. 



1. TN my Mathematical Researches (p. 20), I have shown 

 A that if the roots of the equations 



a?"»+Aia?"»-»+Ajja7'"-2-f . . +A„=0, 



ym ^ ^t^ym- 1 4. A'^^-^ + . . + A'« = 0, 



be so related that 



* Communicated by the Author. 



