Depending on the version of the story, the ship augurs bad weather, and may also appear on the Saturday between Christmas and New Year's.
The tales hold that the ship is the ghost of one that wrecked on the island's northern point shortly after Christmas 1738.
And while there's good evidence that a British ship, the Princess Augusta, carrying a load of passengers from territory that would become Germany, ran aground on the island on Dec. 27, 1738, there's accord on little else about the incident.
A deposition taken from the ship's crew shortly after the incident and republished in 1939 tells of a voyage in which provisions were scarce, half the crew had died, and others were hobbled by the extreme cold.
In the document, crew members said a heavy snowstorm drove the ship aground. They testified that Captain Andrew Brook encouraged those on the ship to save what they could of it and its cargo ''both before and after She broke to Pieces. . . ."
According to folklorist Michael Bell, of Cranston, within the century after the incident, two versions of the story became popular.
The on-island version told of the residents' generosity rescuing and nursing back to health the ill and starving passengers, who had been abused and exploited by the captain or the crew. The other version was immortalized by the 19th-century poet and abolitionist John Greenleaf Whittier.
Whittier's ''The Palatine" appeared in The Atlantic Monthly in 1867. In it, Block Islanders recall the wreck and some islanders' roles in causing it by igniting false signal lights to draw the ship aground.