476 



BOOK X. 



A — Cake. B — Stone. C — Hammer. D — Brass wire. E — Bucket containing water. 



F— Furnace from which the cake has been taken, which is still smoking. 



G — Labourer carrying a cake out of the works. 



The ashes which pass through the sieve are of the same use as they were 

 at first, for, indeed, from these and pulverised bones they make the cupels. 

 Finally, when much of it has accumulated, the yellow pompholyx adhering to 

 the walls of the furnace, and likewise to those rings of the dome near the 

 apertures, is cleared away. 



I must £dso describe the crane with which the dome is raised. When 

 it is made, there is first set up a rectangular upright post twelve feet 

 long, each side of which measures a foot in width. Its lower pinion turns 

 in a bronze socket set in an oak sill ; there are two sills placed crosswise so 



V 



It is obvious from the context that he means saturated furnace bottoms — the herdpley of the old 

 German metallurgists — and, in fact, he himself gives this equivalent in the Interpretatio, and 

 describes it in great detail in De Natura Fossilium (p. 353). The derivatives coined one time 

 and another from the Greek molybdos for lead, and their appHcations, have resulted in a 

 stream of wasted ink, to which we also must contribute. Agricola chose the word molybdaena 

 in the sense here used from his interpretation of Pliny. The statements in Pliny are a hopeless 

 confusion of molybdaena and galena. He says (xxxiii, 35) : " There are three varieties of 

 " it (htharge) — the best-known is chrysitis ; the second best is called argyritis ; and 



" a third kind is called molybditis Molybdiiis is the result of the smelting of 



" lead. . . . Some people make two kinds of litharge, which they call scirerytis and 

 " peumene ; and a third variety being molybdaena, will be mentioned with lead." (xxxiv, 

 53) : " Molybdaena, which in another place I have called galena, is an ore of mixed silver 



