These two volumes provide the basis for the theories expressed in Hamlet's Mill, by de Santillana and von Dechend. Here called the astral theory, it supposes that mythology is directly linked to astronomy, and that mythological motifs describe astronomical observations, such as the movement of planets, and the precession of the equinoxes. For comparative mythologists, the copious illustrations are a treat, since as we know many motifs are illustrated rather than spelled out. The translation is good, with few extra-long, convoluted German-type sentences. Published in 1911, the book must be read in light of subsequent archaeological finds and interpretations. Fans of Hamlet's Mill will find a slightly clearer version of the theory spelled out here in greater detail. Since the book is rare and expensive, its presence here is welcome to scholars and amateurs alike.