What type of text is the fourth letter from Columbus?
Because the trade routes to China and India were controlled by the Turks, an alternative route was of importance to the Europeans. Christopher Columbus believed that he could find a shorter route by sailing West in order to get to China. After having been nearly killed when his ship burned by French pirates and he had to swim to a Portugese shore, Columbus had difficulty convincing anyone to finance his voyage of discovery. After the king of Portugal rejected him, Columbus took his plan to Genoa and then Venice, but was also rejected by his countrymen. Finally, he took his plans to Isabella of Castille and Ferdinand of Aragon, in 1486, but was only granted three small ships for a scouting voyage after the Spanish ended their battles with the Muslims.
As he was under the auspices of the monarchy of Spain, Columbus corresponded with them along his voyages. These letters written by Columbus are called reports that were taken from his personal journals/logs, as all ship captains keep. His fourth letter begins in a manner that evinces the style of a captain's log would have
Most serene and very high and mighty princes, the king and queen, our sovereigns: From Cadiz, I passed to the Canaries in four days and thence, in sixteen, to the Indies,...my course lay to the island of Jamaica, and I wrote this in the island of Dominica. Until I arrived there, I had most excellent weather. On the night that I came there, a great storm burst, and ever since bad weather has pursued me.
Of course, the monarchs would be more interested in reports on discoveries of land and gold and such. In his letter, however, Columbus writes mostly of the terrible weather which he has encountered and of the islands. In Carambaru he found natives "who had the mirrors of gold, bartered them at the rate of one for three hawks' bells, although they were ten or fifteen ducats in weight." Columbus boasts of how cheaply he obtained this gold, knowing his barter would please Queen Isabella. Then, he concludes with his firm theory,
I say that the world is not so great as the vulgar believe, and that a degree from the equinoctial line is fifty—six and two—thirds miles; easily this may be proved exactly. I leave this subject, inasmuch as it is not my intention to speak of this matter, but only to give an account of my voyage, hard and toilsome, although it is the most noble and profitable.