BOOK XXXIV. Liii. 173 Liv 175 



LIII. There i.s also molybdaena " (which in another ^Moiybdama. 

 place we have called galeiia) ; it is a mineral com- xxxiii, 

 pound of silver and lead. It is better the more xxxW 

 golden its colour and the less leaden : it is friable io9- 

 and of moderate weight. \Vhen boiled with oil it 

 acquires the colour of Hver. It is also found adhering 

 to furnaces in which gold and silver are smelted ; in 

 this case it is called metallic sulphide of lead. The 

 kind most highly esteemed is produced at Zephyrium. 

 Varieties with the smallest admixture of earth and of 

 stone are approved of ; they are melted and washed 

 Hke dross. It is used in preparing a particular 

 emolhent plaster for soothing and cooling ulcers 

 and in plasters which are not applied with bandages 

 but which they use as a liniment to promote cicatriza- 

 tion on the bodies of delicate persons and on the 

 more tender parts. It is a composition of three 

 pounds of sulphide of lead and one of wax with half 

 a pint of oil, which is added with soHd lees of oHves 

 in the case of an elderly patient. Also combined 

 with scum of silver and dross of lead it is appHed 

 warm for fomenting dysentery and constipation. 



LIW ' Psimithium ' also, that is cerussa or lead sugarof 

 acetate,* is produced at lead-works. The most ^^^' 

 highly spoken of is in Rhodes. It is made from 

 very fine shavings of lead placed over a vessel of 

 very sour vinegar and so made to drip down. What 

 falls from the lead into the actual vinegar is dried 

 and then ground and sifted, and then again mixed 

 with vinegar and divided into tablets and dried in 

 the sun, in summertime. There is also another way 

 of making it, by putting the lead into jars of vinegar 

 kept sealed up for ten days and then scraping off the 

 sort of decayed metal on it and putting it back in 



253 



