PURIFICATION OF MERCURY. 51 



soluble was tin, iron, and lead ; the insoluble, antimony, with 

 traces of copper and arsenic. (Ding. Polytech. J. cviii. 25.) 



Tin Plate. — Budy and Lammatsch propose alloying tin 

 with yg of nickel, previously to coating sheet-iron with the 

 alloy. The advantages contemplated are, greater hardness, 

 and less fusibility, and the greater cost is said to be com- 

 pensated by a saving of one-half of the quantity of tin usually 

 employed. (An. Rep. Liebig and Kopp, ii. 278. 



5. Zinc, Mercury, and Arsenic. — These three metals, being 

 volatile, are obtained in a similar manner ; the first two by 

 distillation, and the last by sublimation. 



The most important ore of zinc, hitherto worked, being 

 calamine, both silicate and carbonate, it is mixed with lime to 

 retain the silica and with carbon to reduce the oxide, and the 

 mixture distilled in earthenware retorts. Blende, or the sul- 

 phuret of zinc, is abundant, but less easily and more rarely 

 worked. The celebrated locality of red oxide of zinc and 

 Franklinite, near Franklin, New Jersey, has attracted much 

 attention at different times, and although the attempts to distil 

 metal from it have been unsuccessful, it has recently been 

 worked with renewed energy in order to manufacture the pig- 

 ment zinc-white (see Metallosalines). Besides this locality 

 of red zinc-ore, we also have a large formation of calamine 

 in Pennsylvania, and it fi'cquently accompanies the lead-ores 

 of Illinois, &c. 



Mercury occurs as a sulphuret, which is mixed with lime 

 and distilled. A notable locality of the native cinnabar has 

 been opened in California, but the superior attractions of 

 gold-washing, or washing for gold, has prevented a fair de- 

 velopment of the ore. The analysis of one specimen yielded 

 upwards of 60 per cent, mercury, of another more than 30 per 

 cent. The last was from an average of many pounds of ore. 

 The ore presented a beautiful contrast of the red cinnabar 

 with a white quartzose vein, and the cinnabar contained 

 hydrated oxide of iron and bitumen. — J. C. B. 



Purification of Mercury. — Ulex's method of purifying 

 commercial quicksilver was formerly employed in Struve's 



