METALLURGY. 247 



* 

 resembling tin, which is dug near Malacca*. With due deference 



to his authority, I would observe, that Indian calaem is not like 

 tin. Many years ago the Dutch took a Portuguese vessel which 

 was laden with calaemt ; and from all the experiments which were 

 made upon that substance, it appeared to be zinc, or that metallic 

 substance which we in Europe have very lately learned the method 

 of extracting from calamine. Both calamine and zinc have the 

 property of changing copper to a yellow colour; and this is the 

 most distinguishing property of them both; it is that for which 

 they are both sought after in commerce : and as climia and calaem 

 have the same radical letters, and denote in the Arabic and Indian 

 languages two substances which agree in one of their most charac- 

 teristic properties, I leave it to others to determine whether they 

 are not the same word, and in which of the two languages that 

 word was originally formed. The other ore of zinc is called by 

 the Germans blende, from its blinding or misleading appearance ; 

 it looking like an ore of lead, but yielding (as was formerly 

 thought) no metallic substance of any kind*. A particular sort 

 of lead ore has been called by Pliny, galena, from a Gre k word 

 signifying to shine, because it is composed of shining particles; 

 our potters ore and the Derbyshire lead ore are of this sort : blende 

 much resembles galena; but, yielding no lead, it has been called 

 false or pseudo. galena, or mock- lead: our English miners have 

 called it blackjack, and that is the name by which it is known to 

 the makers of brass. Blackjack resembles lead ore so much, that 

 the miners sometimes succeed in selling, to inexperienced smelter*, 

 blackjack instead of lead ore : 1 have heard of the fraud being 

 carried to BO great an extent in Derbyshire, that from a ton of ore 



* Cadmia Arabihus dicitur climia, quod qiiidam pronunciarunt calimia, unde 

 Grace is rccentioribus xfAt/uia interdum scribiiur, unde nostris Gallis calami na 

 Ct lapis calami naris : qua in vocem quidaro praepostere deducunt ab Indico ca- 

 laem, quod metalli genus est stanno simile, baud longc ex Malacca erui ioli- 

 tum. Salm. de Homony. Hy. lat. C. CXII. 



t Savotns de Num. P. II. C. XIV. 



\ PseuJo-palena nomen suum exinde acquisivit, quod faciem quasi miner* 

 plumbeae prae se feral, sed mentiatur, cum id revere non cuntineat quod ex- 

 (erno aspectu pollicelur. Germania appcllatur blende, a blenden j quia, cum 

 falso speciem miners saturnine prae se fcrt, exinde oculos fa-cinei, vel iis 

 imponat. Pott de Pseudo-galena, p. 106. They nave in Staffordshire a ort 

 of iron, which they call blende-metal, of which they make nailr, hammers, 

 Arc. Plot's Staff. 



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