addressed to Florentine official Piero Soderini, dated 1504 and published the following year, purports to be an account by Vespucci of a voyage to the New World, departing from Spain on 10 May 1497, and returning on 15 October 1498. This is perhaps the most controversial of Vespucci's voyages, as this letter is the only known record of its occurrence, and many historians doubt that it took place as described. Some question the authorship and accuracy of the letter and consider it to be a forgery. Others point to the inconsistencies in the narrative of the voyage, particularly the alleged course, starting near Honduras and proceeding northwest for 870 leagues (about )—a course that would have taken them across Mexico to the Pacific Ocean. Certain earlier historians, including contemporary Bartolomé de las Casas, suspected that Vespucci incorporated observations from a later voyage into a fictitious account of this supposed first one, so as to gain primacy over Columbus and position himself as the first European explorer to encounter the mainland. Others, including scholar Alberto Magnaghi, have suggested that the Solderini letter was not written by Vespucci at all, but rather by an unknown author who had access to the navigator's private letters to Lorenzo de' Medici about his 1499 and 1501 expeditions to the Americas, which make no mention of a 1497 voyage. The Soderini letter is one of two attributed to Vespucci that were edited and widely circulated during his lifetime. Voyage of 14991500 In 1499, Vespucci joined an expedition licensed by Spain and led by Alonso de Ojeda as fleet commander and Juan de la Cosa as chief navigator. Their intention was to explore the coast of a new landmass found by Columbus on his third voyage and in particular investigate a rich source of pearls that Columbus had reported. Vespucci and his backers financed two of the four ships in the small fleet. His role on the voyage is not clear. Writing later about his experience, Vespucci gave the impression that he had a leadership role, but that is unlikely, due to his inexperience. Instead, he may have served as a commercial representative on behalf of the fleet's investors. Years later, Ojeda recalled that "Morigo Vespuche" was one of his pilots on the expedition. The vessels left Spain on 18 May 1499 and stopped first in the Canary Islands before reaching South America somewhere near present-day Suriname