Crushing gold bearing ores in mills similar in principle to flour mills. Bottom left goats in treadmill: horizontal power transferred to mill,A,through crown-and-pinion. Bottom right men turn capstan and power transferred through tooth-and-pinion. From Agricola De re metallica Basle 1556. Woodcut | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / UIG / Universal History Archive |
Taille de l’image : | 3225 px × 5419 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |