Their range extended from the Red Sea and Persian Gulf south to eastern Africa and the Spice Islands, but they dared not venture into the unknown of the South Atlantic, due to the fearsome waves of the Agulhas Current.

Meanwhile, first the Portuguese and then the Spanish were exploring southward, establishing bases along the west coast of Africa, and in 1488 Bartolomeu Diaz rounded the Cape of Good Hope. This set the stage for Vasco da Gama to round the Cape and finally reach India (1498), in an effort to reduce dependence on Arab traders for spices and other valued products from the Orient. Portuguese success led to Spanish concerns that the Portuguese would dominate the lucrative trade with east Asia, and eventually prepared the way for Columbus to prevail in his quest for royal approval of a voyage west—the “backdoor” route to the Spice Islands and the riches of the Orient.


Along with his discovery of the New World was Christopher Columbus’s great achievement of recognizing that there was something different about the winds that originated around the Canary Islands. Here were winds that were westerly and constant, as opposed to the variable winds encountered sailing down the coast. Without realizing it, Columbus had discovered the Northeast Trade Winds.7

Columbus’s passage across the Atlantic was remarkable. His log shows days of steady sailing at speeds of 6, 8, and even 10 knots through calm seas. No major storms were encountered. Columbus knew that he could return to Spain by first sailing northeast to catch the westerlies—the winds that blew east across the Atlantic, and that is exactly what he did.

Fernão Magalhães (Magellan) was Portuguese and, like Columbus, sought the support of Spain when Portugal refused to support his grand plan to go east by sailing west. Eventually he secured the support needed, and on September 20, 1519, he sailed from Spain into the Atlantic with a fleet of five vessels, known thereafter as the Armada de Molucca. Six months later, battered by recurring storms and waves that

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