Great Pyramid of Cheops at Giza as astronomical observatory,showing how the passage to the subterranean chamber (not shown) acted as an observing tube,and how the passage on upper left could be used to observe time of solstice and equinox. Illustration of Piazzi Smyth's theory. Wood engraving 1891 | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / UIG / Universal History Archive |
Taille de l’image : | 6000 px × 3728 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |