AT precisely 2.20am this morning, exactly 100 years had passed since a Glasgow minister named Reverend John Harper took his place in the annals of bravery and sacrifice.

As the Titanic slipped below the water in the early hours of April 15, 1912, Harper, aged 39, gave up his life jacket to a fellow passenger and as he plunged into the Atlantic with the 1514 other men, women and children who died that night, he offered consolation and kindness to those who had just minutes to live. Survivors told how Harper preached the Gospel throughout the disaster, even converting those in the freezing water before dying himself.

Those who lived recalled him reciting from Acts 16:31: "Believe in the Lord Jesus and you will be saved."

Yesterday, the life and selfless death of Harper were remembered in a church service in a corner of Glasgow. Across the water in Belfast – the city which built Titanic and is now capitalising on a tourist drive on the back of the disaster – a multi-million pound musical extravaganza was staged to commemorate a maritime disaster that has become part of the story of mankind.

Harper, a widower, had been en route to Chicago with his six-year-old daughter Nan to preach at the Moody Church in West Chicago when the doomed liner sank.

To remember Harper's legacy, the current Chicago minister visited Glasgow this weekend. Harper's granddaughter Mary Gurling, of Cumbuslang, was also among those who gathered at Craigton Cemetery in Cardonald for a memorial service.

A weekend celebrating the life of the Baptist minister has been centred around the Harper Memorial Church in Govan, which was named after the Titanic victim who spent his early career in the area.

Gurling, whose mother was Nan, who survived after being passed onto a lifeboat by her father, said: "It's one of those things that is with you all the time but when you have an anniversary it makes it more real, or unreal, as the case may be.

"When we were growing up, it was just a fact of life that my mother was a Titanic survivor. She didn't talk about it because in those days you didn't talk about things. As she got older, she talked a wee bit more, particularly around the time there was talk of raising the Titanic. That was when she learned she was the last Scottish survivor alive."

Nan Harper, whose married name was Pont, died in 1986. Her daughter said her mother's dislike of still water only started to make sense after she watched a film recreation of the Titanic disaster, and learned that the ocean was motionless on the night of the sinking.

After the boat collided with an iceberg, Harper woke his daughter, wrapped her in a blanket and kissing her goodbye. She was passed to a crewman along with Jessie Leitch, the minister's niece, and they were both put in a lifeboat.

Craig Dyer, a former minister at the Harper Memorial Church, said the Titanic legacy was particularly potent given the "expectations of this most luxurious ship of its time and the sudden turn around in events".

He added: "It's emblematic of a great equaliser. You have all these people travelling in first, second or third class but when it came down to it, it was a life and death issue with death having no regard to these divisions. Harper died preaching the message that he lived preaching and that is very important to us."

Meanwhile, the man who found the wreck of the Titanic said the site could become an underwater museum. Footage of the doomed vessel from 4000m under the ocean off the coast of Canada could be broadcast live, said Dr Robert Ballard.

The oceanographer uncovered the vessel in 1985 and said the technology now existed to beam images from the depths across the world.

"I see the Titanic becoming an underwater museum, accessed, with wonderful facilities," he said. "We hope to come live on the anniversary of the discovery, September 1."

He was speaking at the £100 million Titanic Belfast tourist attraction which has attracted more than 40,000 visitors since it opened on March 31.