Columbus led his fleet to the Portuguese island of Porto Santo, his wife's native land. He then sailed to Madeira and spent some time there with the Portuguese captain João Gonçalves da Camara, before sailing to the Canary Islands and Cape Verde. As he crossed the Atlantic, Columbus discovered that the angle between North as indicated by a magnetic compass and North as measured by the position of the pole star changed with his position (a phenomenon now known as "compass variation"). He would later use his previous measurements of the compass variation to adjust his reckoning.
After being becalmed for several days in the doldrums of the mid-Atlantic, Columbus's fleet regained its wind and, dangerously low on water, turned north in the direction of Dominica, which Columbus had visited in his previous voyage. The ships sighted the land of Trinidad on 31 July approaching from the southeast. The fleet sailed along the southern coast and entered Dragon's Mouth, anchoring near Soldado Rock where they made contact with a group of native Amerindians in canoes. Columbus then landed on Trinidad at Icacos Point (which he named Punta de Arenal) on 2 August. After resupplying with food and water, from 4 to 12 August Columbus explored the Gulf of Paria, which separates Trinidad from what is now Venezuela, near the delta of the Orinoco River. He then touched the mainland of South America at the Paria Peninsula.
Columbus correctly interpreted the enormous quantity of fresh water that the Orinoco delivered into the Atlantic Ocean as evidence that he had reached a continental landmass. As he sailed the Gulf of Paria, he observed the diurnal rotation of the pole star in the sky, which he erroneously interpreted as evidence that the Earth was not perfectly spherical, but rather bulged out like a pear around the new-found continent. He also speculated that the new continent might be the location of the biblical Garden of Eden. He then sailed to the islands of Chacachacare and Margarita. He sighted Tobago (which he named "Bella Forma") and Grenada (which he named "Concepción").
Third voyage
In poor health, Columbus returned to Hispaniola on 19 August, only to find that many of the Spanish settlers of the new colony were in rebellion against his rule, claiming that Columbus had misled them about the supposedly bountiful riches of the New World. A number of returning settlers and sailors lobbied against Columbus at the Spanish court, accusing him and his brothers of gross mismanagement. Columbus had some of his crew hanged for disobedience. He had an economic interest in the enslavement of the Hispaniola natives and for that reason was not eager to baptize them, which attracted criticism from some churchmen An entry in his journal from September 1498 reads: "From here one might send, in the name of the Holy Trinity, as many slaves as could be sold.
Columbus was eventually forced to make peace with the rebellious colonists on humiliating terms. In 1500, the Crown had him removed as governor, arrested, and transported in chains to Spain (see "Accusations of tyranny during governorship" section below). He was eventually freed and allowed to return to the New World, but not as governor.
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