William Pearlman, a dauntless nomad best known as "Poppa Neutrino" who once sailed across the Atlantic on a raft built of junk, died Jan. 23 in a New Orleans hospital of complications from congestive heart failure. He was 77.

A California native who had been at various times a preacher, a gambler and a sign painter, Mr. Neutrino traveled the country in a state of exuberant homelessness. He raised his children as members of a busking street band. They called themselves the Flying Neutrinos, after subatomic particles that zoom about at close to the speed of light.

Wherever the Neutrinos landed, they made home on rafts they built out of old timbers, plastic foam or whatever else the world had discarded.

In 1998, Mr. Neutrino set out to cross the Atlantic in one of these floating creations: "Son of Town Hall," a 51-foot, 17-ton contraption built out of New York City garbage and once described as a "garden shed on water."

Accompanied by three dogs and three crew members - including his fourth wife - he headed east from Newfoundland. Several weeks into the voyage, the raft's three sails filled with the ripping winds of a gale that lasted 15 hours.

"At that point," Mr. Neutrino later said, "I thought, 'I really am sick in the head.' "

They survived that gale, as well as near-collisions with tankers and icebergs. When they ran out of food, they were resupplied by the curious and sympathetic crew of a Russian freighter. After 60 days at sea, the Neutrinos arrived in Ireland.

Theirs was the second successful raft trip across the North Atlantic. (The first was by Henri Beaudout, a Canadian who crossed in 1956.) But Mr. Neutrino's party was the first to make the journey on a raft built out of trash.

"It seems to me we have broken the scrap barrier," he said at the time.

The footloose folk hero became the subject of a film documentary, "Random Lunacy," by Vic Zimet and Stephanie Silber, and of a biography by Alec Wilkinson, "The Happiest Man in the World."

"When I was a child, I had an intuitive knowledge that human life was 99 percent defeat," Mr. Neutrino told Wilkinson, "and that you had to do something extraordinary to turn it into victory."

William David Pearlman was born on Oct. 15, 1933, in Fresno, Calif. He grew up moving from one cheap hotel to the next with his mother, a gambler. He estimated that he had attended 40 or 50 schools by the time he dropped out.