110 PLIirr's NATUBA.L HISTORY. [Book XXXIII. 



making a very inferior kind of green and extremely deeep- 

 tive.^° 



CHAP. 28. SEVEN EEMEDIES DERIVED FROM CHRTSOCOLLA. 



Chroysocolla, too, is made use of in medicine. In combina- 

 tion with wax and oil, it is used as a detergent for wounds ; 

 and used by itself in the form of a powder, it acts as a desic- 

 cative, and heals them. In cases, too, of quinsy and hardness 

 of breathing, chrysocoUa is prescribed, in the form of an elec- 

 tuary, with honey. It acts as an emetic also, and is used as an 

 ingredient in eye-salves, for the purpose of effacing cicatriza- 

 tions upon the eyes. In green plasters too, it is used, for 

 soothing pain and making scars disappear. This kind of 

 chrysocoUa^' is known by medical men as *'acesis," and is alto- 

 gether different from orobitis. 



CHAP. 29. THE CHRTSOCOLLA OF THE GOLDSMITHS, KNOWN ALSO 



AS SANTERNA. 



The goldsmiths also employ a chrysocoUa^^ of their own, for 

 the purpose of soldering gold ; and it is from this chrysocoUa, 

 they say, that all the other substances, which present a similar 

 green, have received their name. This preparation is made 

 from verdigris of Cyprian copper, the urine of a youth who 

 has not arrived at puberty, and a portion of nitre. ^^ It is then 

 pounded with a pestle of Cyprian copper, in a copper mortar, 

 and the name given to the mixture is " santerna." It is in this 

 way that the gold known as *' silvery "^^ gold is soldered ; one 

 sign of its being so alloyed being its additional briUiancy on 

 the application of santerna. If, on the other hand, the gold 

 is impregnated with copper, it will contract, on coming in 

 contact with the santerna, become dull, and only be soldered 

 with the greatest difficulty : indeed, for this last kind of gold, 

 there is a peculiar solder employed, made of gold and one- 

 seventh part of silver, in addition to the materials above-men- 

 tioned, the whole beaten up together. 



^^ As to durability, probably. 



^^ It was tbe mineral, probably, in an unprepared state. 

 32 Gold-glue or gold-solder. 



3^ See B, xxxi. c. 46, as to the " nitrura " of Pliny. Galen, in de- 

 scribing tbe manufacture of " santerna," omits the nitre as an ingredient, 

 ai « Argentosum." The "electrum," probably, mentioned in c. 23. ' 



