Famous second-century work on astronomy written by Ptolemy of Alexandria and first made know to medieval Europe through Arabic translation.

(二世纪左右一本著名的)天文学论者(为亚历山大的托勒密所写，最先以阿拉伯译文传入中世纪的欧洲)。

Any of various medieval works on astrology, alchemy, etc.

(中世纪)天文学或炼金术方面的著作。