When David Eno was a fourth-grader in Canton, N.Y., he chose as a book report subject the legendary sinking of the RMS Titanic. But even to his 9-year-old mind some things didn't add up.

Here was the world's greatest ship, mortally wounded by an iceberg 390-odd miles off the coast of Newfoundland, slowly sinking on a starlit, mirror-calm sea while its 1,500 doomed passengers and crew blinked frantic signals to another ship stopped tantalizingly close. And they got no response.

Why?

And the crew of the other ship -- the SS Californian, halted in ice some miles away -- reported seeing eight distress rockets from a vessel in the distance, but no blinking signal lights. When they inquired what was wrong, with Morse code signals of their own, nobody blinked back.

Why?

For nearly 80 years, the unanswered questions surrounding the Titanic's last hours have spawned a cottage industry of theorists divided sharply into two camps. One group accepts the verdict of government inquiries in England and America that blamed the inaction on the Californian's skipper, Capt. Stanley Lord. Testimony showed Lord slept through most of the Titanic's final hours, despite reports of rockets fired from a ship in the distance. He died in ignominy, protesting his innocence.

The other group believes him. They think Lord was made a scapegoat by the British government and the White Star Line, who needed a villain to help shoulder the blame for the century's deadliest marine disaster.

These "Lordites" believe that neither ship could see the other's signals because the two were too far apart; that instead of seeing each other, they were each seeing a third ship, a "mystery ship" -- or perhaps two mystery ships -- halted somewhere between them. For reasons still unknown, the mystery vessel or vessels never helped out.

Reenter David Eno.

Eno's childhood fascination with the Titanic never deserted him. His unanswered questions about the shipwreck multiplied over the years, through a career that took him from town cop in Canton to police reporter in Connecticut to assistant commissioner of prisons for the state of New York to his present post as an investigator with the Federal Credit Union Administration in Washington.

At some point -- he can't remember precisely when -- he began thinking of the Titanic less as history than as another police case he wanted to solve.

In 1962 he heard of a recurring suspect for the "mystery ship" -- a steam-powered Norwegian schooner called the Samson, reported by one of its officers to have been near the Titanic when the huge liner sank. Citing a tangle of circumstantial evidence, most scholars concluded it couldn't have been there. Eno wasn't so sure.

He set out upon a curiously single-minded quest. During his off-duty hours over the past 13 years, he says, he has assembled a 170-member network of volunteer investigators ranging from a transplant surgeon in Washington who speaks Icelandic, to a fifth-grade class in Winchester, Va., that researched the Newfoundland fishing and sealing fleets of 1912. He peppered Scandinavian police stations with letters, appealing for investigative help.

Last year, even as the British government, under the insistent prodding of the Lordites, began a reappraisal of its own 1912 investigation into Lord's role in the disaster, Eno flew to Iceland, and there in a nursing home near the Arctic Circle, he says, found two elderly men who remember the Samson and at least part of her voyage.

Eno, now 49, and his collaborator, 33-year-old Lt. Cmdr. Craig McLean of the National Oceanic and Atmospheric Administration, believe they have finally dismantled the arguments of those who contend the Samson couldn't have been within visible range of the Titanic on the night it went down, April 14, 1912.

What Eno and McLean offer is a modest but intriguing addition to the controversy that still engulfs the tragedy of the Titanic. Their evidence is likely to satisfy few Titanic buffs, most of whom have long since positioned themselves immovably in one camp or another. But it will help keep alive and roiling one of the most enduring seafaring mysteries of all time.

The Samson's Witnesses

The Samson, a Norwegian sealing ship, has long been a part of the Titanic lore. After the disaster, its former first officer, one Henrik Naess, told a newspaper in Norway that The Samson had been within sight of the Titanic the night the great ship went down.

According to Naess's story, the 147-foot steam-powered schooner with eight seal-hunting boats and a crew of 45 aboard, had been cruising in an ice field north of the Titanic's position the night of April 14, when the crew spotted two masthead lights and rockets on the horizon. Naess sent a man into the crow's nest with binoculars for a better view, and he returned with a report of "many lights" on the sea where the rockets were being fired.

The Samson had been sealing illegally off the coast of Labrador and Newfoundland, and Capt. Carl Johann Ring was wary of being discovered with his cargo, even in international waters, Naess said.

Having no radio, they had no way of knowing the scope of the disaster unfolding and thought the most discreet move was to leave the scene. Only the following month, when the ship put into Isafjordur, Iceland, for repairs did the ship learn of the Titanic's sinking, Naess said.

Scholars of the Titanic found Naess's story intriguing but contradictory in some places and simply baffling in others. For example, Naess stated that his ship had been south of Cape Hatteras, which was not only physically impossible but logically confounding. Why would a Norwegian sealer even think of being near Cape Hatteras? It's a thousand miles from his Arctic hunting ground and nowhere near any seals.

Neither Capt. Ring nor other Samson crewmen, apparently, ever made any public statement about the Titanic. Moreover, a British researcher and lifelong Titanic scholar, Leslie Reade, obtained microfilmed records from Iceland in 1973 that appear to show that the Samson arrived in Isafjordur on April 6 and again on April 20, 1912, which would have made it impossible for the ship to have been hundreds of miles away at the Titanic site on April 14.

"Naess's story has been known for nearly 80 years as 'the Norwegian fairy story,' " says Edward P. de Groot, a Dutch authority on the Titanic. Sailors from the time of Sinbad, he points out, have been notorious for stretching the truth of their adventures, and dozens of claims from seamen to have been potential saviors of the Titanic's passengers have been heard over the years. "They never check out," says de Groot. "There is no conclusive proof that the Samson had any more to do with the Titanic than the Flying Dutchman."

It was those doubts that Eno sought to dismantle when his research brought him to the nursing home in Iceland.

Two men there, older than the Titanic, confirmed that the Samson had been in Isafjordur in May 1912 -- and not before, he said. "The reason they remembered," Eno said, "is that the crew of the ship had gone on a spree and almost wrecked the town. They'd accosted women on the street and even gone into people's homes, and in the end a citizens protection league had been formed to round up the sailors, get them back on the ship and force the ship out to sea. It was a highly memorable event in the town's history."

The disputed dates in April, Eno says, displaying affidavits from port authorities, were actually the recorded dates when the ship had been expected to arrive, and when the Norwegian consul had made an advance payment of half the Samson's harbor fees. The 1912 shipping lists from Lloyds of London place the Samson in Isafjordur on May 14.

Eno got further help from Irene Erickson of Leesburg, a Norwegian woman he met in church in Purcellville, who happensed to be from the town of Arendal, Norway, where the Samson was built, and who volunteered further research on the vessel while home on a visit.

She discovered that in Norway, first officer Naess is still looked on, long after his death, as a man of substance and credibility. He had been a highly skilled seaman and explorer and the most accomplished ice pilot of his day, and had been decorated by both Norway and Sweden for his role in various Arctic rescues. He does not sound like the sort to elaborate stories, Eno says. He had referred to the Titanic incident in his unpublished memoirs and had told his children and grandchildren that he regretted not having had a radio so the Samson might have saved some of the 1,500 Titanic passengers and crew who died that night. He realized, however, that he couldn't have saved them all.

Erickson, Eno said, even learned one of the reasons why no Titanic researcher in the past 70 years had heard from the Samson's captain: Carl Johann Ring died June 22, 1918, after his ship, the Eglantine, was torpedoed by a German U-boat in the North Sea.

As for the Samson itself, the ship went on to fame from its days as a renegade sealer. Uniquely equipped as an ice vessel, with a steel-reinforced bow and a hull as much as five feet thick in places, it was sought out by Adm. Richard Byrd, the explorer, renamed the City of New York, and shown off in New York and Chicago after service in the Antarctic.

She burned in a fire off Yarmouth, Nova Scotia, in 1951.

"The bow wound up on the beach, and we learned some kid had taken pictures of it the next day," Eno says with a satisfied grin. "Through a cop in Yarmouth we found the name of the kid. He still lives there. He had the pictures in his attic."

The Many Contradictions Just how much all this really means to the story of the Titanic, of course, is problematic. There is, for example, the matter of the Cape Hatteras reference, which Eno and McLean admit they can't explain, and shrug off as an obvious mistaken reference to Cape Race, Newfoundland. And though the Samson could have matched the description of a vessel seen by some of the Titanic's survivors, showing a single white light and appearing to be moving slowly away, it leaves unexplained the vessel seen from the Californian, which was clearly a steamer of some kind.

Eno and McLean say they're working on that. There are many candidates, they say: the area was a major Atlantic shipping route at the time.

McLean and Eno have come to subscribe to the basic theory of the Lordites -- that the rockets seen from the Californian were, in fact, fired from the Titanic, but appeared to be from a separate still undiscovered mystery vessel, far closer than the sinking ship. In all, says Eno, he's been working for 13 years on 74 "corridors of inquiry" into the unanswered questions of the Titanic. So far, he says, he's found 29 "points of corroboration" tending to substantiate Lord's claim of innocence.

Others are less convinced.

"That's fascinating about the Samson if it's true," says Walter Lord, author of "A Night to Remember" and dean of Titanic historians. Though he bears the same surname as the captain of the Californian, he's no relation and remains skeptical of Lordite theories and mystery ships.

"You see, even if the Samson was there, it doesn't exonerate the Californian. Why did they see rockets and do nothing? The testimony of the men on the bridge is that they clearly thought they were distress rockets. The ship they were watching clearly was not behaving normally and looked to be in trouble. They talked about that all night."

Historian Lord, whose judgment on the Californian affair has been solicited by the reopened British board of inquiry, thinks the Titanic and the Californian were about 10 to 12 miles apart when the former hit the iceberg, "near enough to see each other but not near enough to communicate by Morse lamp." His opinions, he says, are based not only on the official records but on a long interview with one of the Californian's surviving watch officers in 1957 while researching "A Night to Remember."

He points out further that the Titanic's rockets weren't the only ones the Californian ignored that night. The ship and its crew also shrugged off rockets the Carpathia fired to encourage the Titanic's survivors as it raced toward the site of the sinking. Nobody on the Californian thought any of the rockets significant enough to wake up the sleeping wireless operator for a radio check. He had bedded down just before the Titanic hit the ice.

That sort of reasoning leaves Eno and McLean undismayed.

"You read through the record of these inquiries," McLean says, "and there are so many contradictions and unanswered questions you just can't believe nobody followed them up. Which is all we're doing. It's like the Kennedy assassination investigation. There was a rush to judgment after the Titanic went down. As a nation we get on these things like we take an escalator. And we always get off at the first floor."

Rubbish, says de Grootfrom across the Atlantic in the Netherlands. He has inherited the exhaustive research documents of Leslie Reade and is finishing a book on "the Titanic-Californian muddle" that Reade was working on when he died two years ago. It is scheduled for publication next year.

"Naess told the Samson story in print four separate times -- in 1912, 1921, 1928 and 1939 -- and it's different every time," de Groot says. Reade's book, he says, will show "the Norwegian fairy tale" for what it is.

Meanwhile, Walter Lord, who's written two books on the Titanic and dwells in a New York apartment packed with Titanic memorabilia, views the enduring scholarly cat fight with equanimity.

"It's such a wonderful story," he says of the great ship's sinking. "It was a metaphor for an age, of course, but there seems to be something in it to fascinate almost everybody." He himself remains skeptical of Eno's findings but says he's eager to know more about them.

"It's a rash man," he says, "who says he knows the final answer to anything having to do with the Titanic."