Lead: Commissioned by King Charles I of Spain to find a short cut through the Americas to the islands of southeast Asia, Ferdinand Magellan in command of five ships left the Spanish port of Seville in August, 1519. Thus began one of history's greatest voyages of exploration.

Intro: A Moment in Time with Dan Roberts.

Content: Prior to the voyages of Columbus beginning in 1492 and the systematic exploration of Africa by the Portuguese in the 1480s and 90s, Europeans had little accurate information about the earth's size. Their knowledge was based on the theories of the second century Greek writer Ptolomy who underestimated it. Because of this geographers were convinced that Japan and China lay only a few thousand miles west of Europe. Columbus's trips proved those estimates to be wrong. With the first accounts of Vasco de Balboa who reported finding a new Pacific Ocean on the other side of the new world in 1513, it appeared that the earth was quite large indeed.

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