Young Frederick Sheath, his mind numbed by visions of hysteria, stepped into Lifeboat One where he joined a shivering woman in a silk kimono.

It was First Officer Murdock, the Officer of the Watch, who had ordered him to leave Titanic. There was no time to argue. No time to even think. That night, just before midnight on April 14 1912, the luxurious White Star liner had hit an iceberg and was now sinking.

Sheath, a 20-year-old Southampton ship trimmer, sat speechless among five First Class passengers as the lifeboat slipped away across the black velvet waters of the North Atlantic.

It was a floating, watery nightmare.

Other lifeboats bobbed nearby and shadowy, thrashing shapes shouted from the water. And then, just after 2am, the mighty, heaving bow of Titanic dipped beneath the surface.

It's impossible to imagine what Sheath's young eyes captured in those last moments. As 1,523 went to their deaths, he may have imagined their agony beneath the waves. Or perhaps Sheath's traumatised mind diverted thoughts to his wealthy lifeboat companions, still wearing their tasteful finery. He surely couldn't have guessed that Titanic's First Class passenger wealth amounted to over a quarter of a billion dollars.

And so Lifeboat One, amid a sea of shrieks, drifted off to safety - and into controversy.

Why had the lifeboat left with just 12 passengers when it could accommodate 40? And what about the woman in the kimono, Lady Duff Gordon, who had been comforted in the lifeboat by her husband, Sir Cosmo? Had he, as rumoured, paid Frederick and fellow crew members £5 for new kit to ensure the lifeboat continued on its way to safety rather than return for survivors?

An inquiry into the doomed maiden voyage across the ocean opened on May 2, 1912 and duly exonerated Sir Cosmo Duff Gordon. But Frederick Sheath, one of 96 witnesses subjected to over 25,000 probing questions, endured a torrid cross-examination. Though spared scrutiny over the £5 bribe allegation, his quick, short answers betrayed his churning anxiety over other matters.

Sheath confirmed he had seen the 46,000-ton Titanic sink. Then came the inevitable supplementary question: "What I want to know is, after Titanic went down, what was done by your boat then? He replied: "We pulled back again to the other boats."

He would not be let off that lightly and the verbal barrage which followed surely resurrected the haunting images of that night:

"When Titanic went down, did you hear the cries?"

"Yes." "Did the cries continue for some time?"

"Yes." "You say that your boat went back. Do you mean that it went back to where Titanic had sunk?"

"I could not say where she sank. I am no navigator."

"That is what you heard the last gentleman (witness) say?"

"No I never."

Sheath left the hearing, one can reasonably assume, with pounding emotions. One fears guilt refused to lie low and resurfaced time and again to deny a rational assessment of his trauma. In the event, it was Sheath's asthma which forced him to abandon a sea-going career and he became a docker instead. He died aged just 42, allowing the compassionate mists of time to fade his association with the doomed liner.

Until now.

His story, and that of many others, currently features in "Titanic - The Exhibition" at Portsmouth Historic Dockyard, where their tales are woven into a chronological account of the disaster. It starts with the $7m construction of Titanic at the Harland and Wolff shipyard in Belfast and moves swiftly on to her departure from White Star Line dock in Southampton. The facts of its fate en route to New York are then dissected before tantalising photographs from the sea bed record the wreck's discovery in September 1985.

Yet it's the artefacts, belonging to seven private collectors, which catch the eye.

The silk kimono worn by Lady Duff Gordon, on public display for the first time, is one of the undoubted highlights. The garment's visible stains are, one is reliably informed, the result of Lady Gordon's seasickness.

Nearby, encased in a black-framed glass cabinet, hangs an original Titanic lifejacket. It was taken from one of four bodies discovered by rescue ship Montmagmy on May 3rd 1912. The canvas jacket was retrieved by the ship's quartermaster who, somewhat bizarrely, used it to teach his daughter to swim.

Its assistance as a swimming aid was surely limited, however, since Titanic's lifejackets were effectively useless. Indeed, the cork-filled pockets merely served to push heads forward into the freezing waters. And, in any case, the unforgiving Atlantic wasteland limited survival time to under 15 minutes.

The exhibition's commercial director Ian Dickinson remains unsurprised by the continuing obsession with Titanic. "It was huge even before James Cameron's 1997 film - and then it just went berserk."

He points to the lifejacket. "That was insured for $100,000 before the film. Now it's $333,000." Meanwhile Lady Duff Gordon's kimono, stains and all, is insured for over $100,000.

Merely utter 'Titanic' and pens are poised over chequebooks. Beneath one glass window lies a small train ticket. It was bought by a Titanic passenger who intended to return from New York and disembark at Plymouth rather than Southampton. The ticket was for the train journey to London and is insured for $10,000.

"Titanic - The Exhibition" is open daily at Portsmouth Historic Dockyard until November 17, 2003.

- Originally published Sept 2003.