Chap. 21.] HOW GOLD IS FOUND. 99 



Btate on the appropriate occasion. ^^ The most convenient me- 

 thod for gilding copper would be to employ quicksilver, or, at 

 all events, hydrargyros ;^° but with reference to these substances, 

 as we shall have occasion to say when describing the nature^^ of 

 them, methods of adulteration have been devised. To effect this 

 mode of gilding, the copper is first well hammered, after which 

 it is subjected to the action of fire, and then cooled with a 

 mixture of salt, vinegar, and alum.'^^ It is then cleansed of all 

 extraneous substances, it being known by its brightness when 

 it has been sufficiently purified. This done, it is again 

 heated by fire, in order to enable it, when thus prepared, with 

 the aid of an amalgam of pumice, alum, and quicksilver, to 

 receive the gold leaf when applied. Alum has the same pro- 

 perty of purifying copper, that we have already^^ mentioned 

 as belonging to lead with reference to gold. 



CHAP. 21. (4.) HOW GOLD IS FOUND. 



Gold is found in our own part of the world ; not to mention 

 the gold extracted from the earth in India by the ants,-* and 

 in Scythia by the Griffins. ^^ Among us it is procured in 

 three different ways ; the first of which is, in the shape of 

 dust, found in running streams, the Tagus*® in Spain, for instance, 

 the Padus in Italy, the Hebrus in Thracia, the Pactolus in 

 Asia, and the Ganges in India ; indeed, there is no gold found 

 in a more perfect state than this, thoroughly polished as it is 

 by the continual attrition of the current. 



A second mode of obtaining gold is by sinking shafts or seek- 

 ing it among the debris of mountains ; both of which methods 

 it will be as well to describe. The persons in search of gold 

 in the first place remove the *' segutiium,"^^ such being the 



ployed for this cement, called ' leucophoron/ one may readily conceive 

 that it must have been a ferruginous ochre, or kind of hole, which is still 

 used as a ground. Gilding of this kind must have suffered from dampness, 

 though many specimens of it are still preserved." — Beckmann's Hist. luv. 

 Vol. JI. p. 294. Bohn' s Edition. i9 B. xxxv. c. 17. 



20 Literally, " fluid silver." " The first name here seems to signify 

 native quicksilver, and the second that separated from the ore by an ar- 

 tificial process." Beckmann's Hist. Inv. Vol. II. p. 72. 



21 In Chapters 32 and 41 of this Book. 



22 As to the identity of the " alumen " of Pliny, see B. xxxv. c. 52. 



23 In the preceding Chapter. 24 gee B. xi. c. 36. 

 25 See B. vii. c. 2. 26 gee B. iv. c. 17. 



2^ Ajasson remarks, that the Castilians still call the surface earth of au- 



H 2 



