Mnaseas is reckoned to have been a pupil of a scholar who was chief librarian at what library?
Eratosthenes Eratosthenes of Cyrene ( ; Greek: Ἐρατοσθένης ὁ Κυρηναῖος , ] ;  – ) was a Greek mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. He invented the discipline of geography, including the terminology used today.
Hegias Hegias (Greek: Ἡγίας ) was a Neoplatonist philosopher who lived in the 5th and 6th centuries. He may have been the great-grandson or great-great-grandson of Plutarch of Athens, the founder of the Neoplatonist Academy in Athens. Hegias studied under Proclus at the school in Athens, when Proclus was an old man c. 480. Proclus showed him great favour, and considered him worthy of hearing his lectures on the Chaldean Oracles.