218 PLINT's NA.TUEAL HISTORY. [Book XXXIV. 



lead "which has been prepared this way is preferred to the 

 Bpodium of Cyprus. 



CHAP. 51. FIFTEEIf EEMEDTES DEEIVED FEOM THE SCOEIA 



OF LEAD. 



The scoria^° of lead is also made use of; the best kind being 

 that which approaches nearest to a yellow colour, without any 

 vestiges of lead, or which has the appearance of sulphur without 

 any terreous particles. It is broken into small pieces and 

 washed in a mortar, until the mortar assumes a yellow colour ; 

 after which, it is poured off into a clean vessel, the process 

 being repeated until it deposits a sediment, which is a sub- 

 stance of the greatest utility. It possesses the same properties 

 as lead, but of a more active nature. How truly wonderful is 

 the knowledge which we gain by experiment, when even the 

 very dregs and foul residues of substances have in so many 

 ways been tested by mankind ! 



CHAP. 52. — SPODIUM OF LEAD. 



A spodium^^ of lead is also prepared in the same manner as 

 that extracted from Cyprian copper.^- It is washed with rain 

 water, in linen of a loose texture, and the earthy parts are 

 separated by pouring it off; after which it is sifted, and then 

 pounded. Some prefer removing the fine powder with a 

 feather, and then triturating it with aromatic wine. 



CHAP. 53. MOLTBD^NA : FIFTEEI^ EEMEDIES. 



Molybdsena,'^^ which in another place I have called 

 " galena,"'''^ is a mineral compounded of silver and lead. It is 

 considered better in quality the nearer it approaches to a 

 golden colour and the less lead it contains ; it is also friable, 

 and of moderate weight. When it is melted with oil, it 

 acquires the colour of liver. It is found adhering also to the 



^'^ This, according to Ajasson, is the protoxide, or probably, in some 

 cases, the arseniate of lead. — B. 



21 From (TTTo^oc, "ashes."— B. 22 gee Chapter 34 of this Book.— B. 



23 This was probably lead ore in its primary state, when only separated 

 from the stannura, and before it was subjected to fusion for the purpose of 

 obtaining pure lead. — See Beckmann's Hist. Inv. Vol. II. p. 211. Bolm's 

 Edition. Ajasson identifies it with litharge, or fused oxide of lead, known 

 as gold and silver litharge, from its colour. 



-* See B. xxxiii, c. 31, and Chapter 47 of this Book. — B. 



