Engraving by Baltard, showing mining tools, shaft construction, and the use of stopes (steps or notches in vertical beams or in the side of a pit). The silver and lead mines illustrated are in Andreasberg, Germany. Illustration from 'De la richese minerale: Considerations sur les mines, usines et salines des differens etats, presentees comparativement' by Antoine-Marie Heron de Villefose (1774-1852), published in Paris in 1819. In English, the title is 'Of mineral riches: Considerations on the mines, factories and salt-mines of different countries, presented comparatively'.
© Science Museum / Science & Society Picture Library