A General History and Collection of Voyages and Travels, Vol. 3 | Page 9

ports, all in their proper places and proportions. During my whole life, I have endeavoured to see and understand all books of cosmography, history, and philosophy; by which my understanding hath been enlightened so as to enable me to sail from Europe to the Indies, and God hath inclined me to put this design into execution. Filled with this desire I came to your highnesses; and after all who had heard an account of my proposed undertaking had rejected it with scorn and contempt as visionary and impracticable; in your highnesses alone I found judgment to believe in the practicability of my proposal, and constancy and spirit to put it into execution."
In another letter, written in January 1495 from Hispaniola, to their Catholic majesties, in illustration of the errors and mistakes common in voyages and the piloting of ships, he thus writes, "I was formerly sent to Tunis by King Renee, whom God hath since taken to himself, to take the galeasse called Fernandina; and, when near the island of St Peter off Sardinia, I was informed that the Fernandina was accompanied by two ships and a carack. This intelligence dismayed my people, who refused to proceed in the enterprize, and demanded to go back to Marseilles for another ship and more men. Finding that it was impossible to go on against their inclinations, without a stratagem, I pretended to yield to their desires; but having altered the card of the ships compass, I set sail when it was late, under pretence of making for Marseilles. But next morning at day-break, when all on board believed we had been sailing for Marseilles, we found ourselves close in with Cape Carthagena[3]."
In a memorandum or observation tending to prove that all the five zones are habitable by the experience of navigation, he thus writes: "In February 1467, I sailed an hundred leagues beyond Thule, or Iceland, the northern part of which is 73 degrees distant from the equinoctial, and not 63 degrees as some suppose; neither does it lie upon the line where Ptolemy begins the West, but considerably more to the westwards. To this island, which is as large as England, the English carry on trade, especially from the port of Bristol. When I was there the sea was not frozen, but the tides were so great that in some places it rose and fell twenty-six fathoms[4]. I have likewise been in the Portuguese fort of St George del Mina, under the equinoctial, and can witness that it is not uninhabitable, as some have supposed." In his book respecting his first voyage, he says that he saw some mermaids on the coast of Menegueta, but that they were not by any means so like ladies as represented in paintings. In another place he says, that, in several voyages between Lisbon and Guinea, he had observed that a degree on the earth corresponds to 56 miles and two thirds. He notices having seen mastick drawn from some trees in the island of Scio, one of the isles in the Greek Archipelago.
In one place of his own writings he says that he had been at sea during twenty-three years, without being on shore for any length of time; and had seen all the countries of the east and west, and towards the north, particularly England and Guinea; yet had never seen any harbours that could be compared for goodness with those which he had discovered in the West Indies. He says farther, "I went first to sea at fourteen years of age, and have followed that profession ever since." In his note book of his second voyage he says, "I had two ships, one of which I left at Porto Sancto, for a certain reason, where it continued one day; and on the day following, I rejoined it at Lisbon[5]; because I encountered a storm, and had contrary winds at south-west, and the other ship had contrary winds at south-east." From these instances it may be inferred that he had great experience in sea affairs, and that he had visited many countries and places, before he undertook his great discovery.

[1] This must be understood as referring to voyages in the Mediterranean, in respect of the port of Genoa.--E.
[2] Supposing Columbus to have been 14 years of age on first going to sea, it may be concluded that he was born in 1447. He must therefore have been 45 years old when he set out in 1492 for the discovery of America; and 59 years old at his death, in 1506.--E.
[3] Or rather Cape Carthago, on the coast of Barbary near Tunis.--E.
[4] It is highly probable that the original translator may have here mistaken the braccio of 1.913 English feet, for the fathom of 6 feet. In fathoms, this tide rises to the incredible