The Sweet Trinity

"The Sweet Trinity", also known as "The Golden Vanity" or "The Golden Willow Tree", is Child Ballad 286. The first surviving version, about 1635, was "Sir Walter Raleigh Sailing In The Lowlands (Shewing how the famous Ship called the Sweet Trinity was taken by a false Gally & how it was again restored by the craft of a little Sea-boy, who sunk the Gally)".
Synopsis.
A captain of a ship (the "Sweet Trinity" or "Golden Vanity" or "Golden Willow Tree" of the title) laments the danger it is in; Sir Walter Raleigh complains that it was captured by a galley, but the more common complaint is that it is in danger from another ship, which may be French, Turkish, Spanish, or (especially in American variants) British. A cabin boy offers to solve the problem. The captain promises him rich rewards, which vary enormously between versions. The boy swims to the enemy ship, bores holes in its hull, and sinks it.
He swims back. Usually, the captain declares he will not take him up, let alone reward him; in some variants, he extorts the rescue and reward by sinking, or threatening to sink, his ship as well, but usually, he drowns (sometimes after saying he would sink the ship if it weren't for the crew). Occasionally, the crew rescue him, but he dies on the deck. In the variant with Raleigh, Raleigh is willing to keep some of his promises, but not to marry him to his daughter, and the cabin boy scorns him. In the New England version recorded by John Roberts (see below), he sinks both ships but is rescued by another one, thus explaining how the story could have been passed on.