Following the trade winds

How America was discovered

The success of Christopher Columbus' first voyage of discovery was due entirely to his boldness in sailing with the prevailing wind behind him. None of the attempts earlier in the century to penetrate the far Atlantic had succeeded, mostly because the ships had tried to guarantee their passage home by prevailing into the prevailing westerlies, which blew across from the the Atlantic to the Azores.

The strength of the westerlies defeated all efforts to sail westwards into the wind, but by starting his Atlantic crossing from the Canaries, farther south, Columbus avoided the problem. He hoped to find the werterlies for his return journey.

When Columbus's ships lfet from Gomera, the most westerly of the Canary Islands, all three were rigged with square sails. This rig was the most effecient when sailing with a wind from behind, but was less effective when sailing against the wind; in this case, the sails had to be turned until they were nearly parallel to the keel, allowing the ships to tack slowly back and forth.

On this first of his three transatlantic voyages, Columbus anticipated a journey of about a month - an execeptionally long spell on the open sea, but one for which ample supplies could be provided for the crew. Ship's biscuits -  with flour to bake more if needed - salt meat and fish, wine, oil, vinegar, pulses and a hard cheese especially made in Gomera for sea-bound vessels were brought on board, as were small quantities of honey, rice, raisins and almonds, used only for those who fell sick.

Cooking on board was discouraged because of the risk of fire, although there was a hearth built among the ship's stone ballast. Sleeping arrangements were similarly primitive, and most men would curl up on deck until Columbus saw hammocks in use in the West Indies. Thereafter, hammocks were provided for the crew.

Columbus claimed that his success in the art of naviagtion was due to "a kind of prophetic vision," but at the same time he was always trying to impress his men by brandishing a chart and hadnling new-fangled gadgets, such as quadrant, on deck. In fact, his methods were simple.

The first task was to keep course. Mariners' normal practice was to steer by the compass, but Columbus seems to have preferred to set his course by the sun and the stars. Although he claimed to check his latitude by regular quadrant sightings, in practice he worked out by timing the hours of daylight by latitude. The errors in his log match the errors printed in a comtemporary table.

Columbus also needed to measure time as accurately as possible in order to estimate how far he had treavelled. He calculated the ship's approximate speed by watching the waterbreak over the bows, and multiplied it by the time lapsed. The ship's boys had the job of turing the hourglass, but Columbus found it more reliable to watch the progress of the stars around the Pole Star, which describe a complete revolution in exactly 24 hours.

A cry from the rigging

Columbus's courage and driving vision kept the men from despair as the days wore on without sight of land, but on October 7, he altered the ship's course to the south-west, writing on October 10 that the men "could endure no more." The very next day, sightings of flotsam multiplied and as night fell everyone was excitedly anticipating land. At two o'clock on the morning of the 12th a lookout up in the rigging peered into the darkness and sent up an excited cry. A shot from a small cannon rang out - the agreed signal for land - and the ships echoed with loud, hearltfelt thanks to God and the holy Virgin.