BOOK XXXIII. xxxiv. 104-XXXV, 107 



applied to it, so that it may not be turned into lead.** 

 Some people do not employ dung in boiling it but 

 fat. Others pound it in water and strain it through 

 three thicknesses of linen cloth and throw away the 

 dregs, and pour ofF the liquor that comes through, 

 collecting all the deposit at the bottom, and this 

 they use as an ingredient in plasters and eye-washes. 



XXXV. The slag in silver is called by the Greeks siag 0/ 

 the ' draw-off.' ^ It has an astringent and cooling *^^^'^* 

 effect on the body, and like sulphuret of lead, of xxxiv. 

 which we shall speak in dealing with lead, it has ^^^ '^^' 

 healing properties as an ingredient in plasters, being 

 extremely effective in causing wounds to close-up, 

 and when injected by means of syringes, together 

 with myrtle-oil, as a remedy for straining of the 

 bowels and dysentery. It is also used as an ingre- 

 dient in the remedies called emollient plasters used 

 for proud flesh of gathering sores, or sores caused 

 by chafing or running ulcers on the head. 



The same mines also produce the mineral called Litharge. 

 scum ^ of silver. Of this there are three kinds, with 

 Greek names meaning respectively golden, silvery 

 and leaden ; and for the most part all these colours 

 are found in the same ingots. The Attic kind is the 

 most approved, next the Spanish. The golden scum 

 is obtained from the actual vein, the silvery from 

 silver, and the leaden from smelting the actual lead, 

 which is done at Pozzuoli, from which place it takes 

 its name.^ Each kind however is made by heating 

 its raw material till it melts, when it flows down from 

 an upper vessel into a lower one and is lifted out of 

 that with small iron spits and then twisted round on 



'^ Litharge, k^ad monoxide. 

 ^ Argyritis Puteolana. 



