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Entry 58 of 240Invention

The Library of Alexandria

c. 295 BCE/Egypt/Ptolemaic Egypt
Today Alexandria, EgyptSpan Ptolemaic Egypt · 305–30 BCE

Alexander's successors in Egypt built a research institution and tried to collect every book in the world, seizing scrolls from ships in the harbour to copy them. What it produced is startling: Eratosthenes measured the circumference of the earth using shadows and got within a few percent; Euclid systematized geometry; Aristarchus proposed the earth goes round the sun, eighteen centuries before Copernicus. The library declined over centuries through funding cuts, expulsions of scholars, and fire — there was no single dramatic burning, which is somehow worse.

◆ Worth knowingShips docking at Alexandria had their books confiscated and copied. The library kept the originals and returned the copies — and noted in the catalogue which volumes had come 'from the ships.'
◆ The mechanismInformation-medium revolution

A new way to record or transmit information lowers the cost of copying ideas and reorders who holds knowledge and power.

Also: State formation & institutional founding · Trade-route shift

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