The greek Eratosthenes by shadows estimated the circumference of the earth to be 250,000 stadia (it’s really 216,000 stadia using the 12.16 modern inch olympic foot), which is about 25,000 nautical miles, and medieval geographers knew the approximate eastward extent of India by Marco Polo’s journeys, about 6,000 miles to the east of Spain, so Christopher Columbus, equipped with only provisions for a 5,000 mile trip, not 19,000, surely knew that what he would discover was not India rather what he would name for the Amuraca tribe (Amorites of Canaan), hence America.
