# Eratosthenes is appointed to the Alexandrian library under Ptolemy III as later lives report Date: 244 ## The fact MacTutor and Britannica print a received appointment of [Eratosthenes](/people/eratosthenes) as librarian at Alexandria under Ptolemy III Euergetes after study in Cyrene, Alexandria, and Athens. Handbook years cluster around the 240s BCE. He did not file a 21st-century library URL. Callimachus and Apollonius remain named predecessors in the same later file. It is one event. ## Context The Mouseion-and-library was a Ptolemaic court institution. Shared work with unnamed copyists, the king’s officers, and later reporters is the point. Elite lock-in of royal books is not invented here as a second twin of the same office. Eratosthenes’s documented role is bounded by other offices and collaborators named in the sources below. Sharing a field with them is not a reason to drop a documented act, and it is not a reason to assign later consequences done in the name after death. Conventional years are c.276–c.194 BCE. Almost no autograph survives. Cleomedes, Strabo, Nicomachus, and later encyclopedias are the public file. Classroom globe reconstructions are not his acts. Contribution is complex. Named person as heading of the dated public instrument. Later editors, museums, printers, or offices share publication. Complex where later carriers are the surviving public file. ## Evidence and sources MacTutor’s Eratosthenes biography and Britannica’s life independently describe the Alexandrian librarianship as a received heading. Official or archival record: MacTutor — Eratosthenes of Cyrene (https://mathshistory.st-andrews.ac.uk/Biographies/Eratosthenes/; University of St Andrews). ## Significance A named librarian at a royal collection is a knowledge-access path. It is not a modern open-stack statute and not a recovered shelf-list autograph. ## What is established and what is not Established: later lives name him as librarian under Ptolemy III. Not established: an exact ISO appointment day, a surviving employment contract, or that every later Alexandrian book was his act. What would change the picture: a contradictory original with a different date or name, or a measured series that can be argued, with lag and alternatives, as a consequence of this instrument rather than of later institutions. The date is the date of this instrument, not a licence to back-date every later harm or benefit. Established here: a sourced, dated public instrument with a named contribution by Eratosthenes. They are not a public rating. Eratosthenes did not file a later UNESCO form, a later Loeb colophon, or a later museum label as a personal act. A portrait or conventional bust is not this mechanism. Allegation, reconstruction, and established occurrence stay distinct. Do not treat a modern reconstruction of the Mouseion plan as this office. Do not date the appointment to a UNESCO listing of Alexandria. Keep the carrier date of later English distinct from the received historical year stored in the date field. Do not read a later English edition as a recovered autograph of Eratosthenes. ## People - Eratosthenes: https://factrail.ai/people/eratosthenes ## Drivers - Digital Learning Access: https://factrail.ai/drivers/edu-digital-learning-access ## Sources - https://www.britannica.com/biography/Eratosthenes - https://mathshistory.st-andrews.ac.uk/Biographies/Eratosthenes/ ## Methodology https://factrail.ai/methodology Canonical: https://factrail.ai/facts/era-library-appointment