Assay laboratory with various forms of furnace including and athanor or 'Slow Harry',7,self-stoking furnace for cementation,9,and barrel-shaped furnace,3,in which draught supplied by steam from water in container placed over hot charcoals. At 4 a crucible is being gradually heated in a ring of burning coals: to increase the heat coals could be raked into a smaller circle. From 1683 English edition of Lazarus Ercker Beschreibung allerfurnemisten mineralischen Ertzt- und Berckwercksarten originally published in Prague in 1574. Copperplate engraving | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / UIG / Universal History Archive |
Bildgröße: | 3482 px × 2509 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |