They were forced to take refuge in Falmouth, Cornwall, from where they returned to Plymouth for repair. After this major setback, Drake set sail again on 13 December aboard "Pelican" with four other ships and 164 men. He soon added a sixth ship, "Mary" (formerly "Santa Maria"), a Portuguese merchant ship that had been captured off the coast of Africa near the Cape Verde Islands. He also added its captain, Nuno da Silva, a man with considerable experience navigating in South American waters. Drake's fleet suffered great attrition; he scuttled both "Christopher" and the flyboat "Swan" due to loss of men on the Atlantic crossing. He made landfall at the gloomy bay of San Julian, in what is now Argentina. Ferdinand Magellan had called here half a century earlier, where he put to death some mutineers. Drake's men saw weathered and bleached skeletons on the grim Spanish gibbets. Following Magellan's example, Drake tried and executed his own "mutineer" Thomas Doughty. The crew discovered that "Mary" had rotting timbers, so they burned the ship. Drake decided to remain the winter in San Julian before attempting the Strait of Magellan. On his voyage to interfere with Spanish treasure fleets, Drake had several quarrels with his co-commander Thomas Doughty and on 3 June 1578, accused him of witchcraft and charged him with mutiny and treason in a shipboard trial. Drake claimed to have a (never presented) commission from the Queen to carry out such acts and denied Doughty a trial in England. The main pieces of evidence against Doughty were the testimony of the ship's carpenter, Edward Bright, who after the trial was promoted to master of the ship "Marigold", and Doughty's admission of telling Lord Burghley, a vocal opponent of agitating the Spanish, of the intent of the voyage. Drake consented to his request of Communion and dined with him, of which Francis Fletcher had this strange account:  Drake had Thomas Doughty beheaded on 2 July 1578. When the ship's chaplain Francis Fletcher in a sermon suggested that the woes of the voyage in January 1580 were connected to the unjust demise of Doughty, Drake chained the clergyman to a hatch cover and pronounced him excommunicated. The three remaining ships of his convoy departed for the Magellan Strait at the southern tip of South America. A few weeks later (September 1578) Drake made it to the Pacific, but violent storms destroyed one of the three ships, the "Marigold" (captained by John Thomas) in the strait and caused another, the "Elizabeth" captained by John Wynter, to return to England, leaving only the "Pelican".