Four hundred years before Eratosthenes

With them he deduced the circumference of the Earth with an error of only a few percent, a remarkable achievement for 2,200 years ago. He was the first person accurately to measure the size of a planet.The Mediterranean world at that time was famous for seafaring. Alexandria was the greatest seaport on the planet. Once you knew the Earth to be a sphere of modest diameter,would you not be tempted to make voyages of exploration, to seek out undiscovered lands,perhaps even to attempt to sail around the planet? Four hundred years before Eratosthenes,Africa had been circumnavigated by a Phoenician fleet in the employ of the EgyptianPharaoh Necho.