He spent a quarter of a century chronicling his life in five-minute segments. In his journal he faithfully recorded his reflections on God and his every visit to the lavatory. He even taped a nostril hair to its pages so that future scientists can study his DNA.

He slept for just two hours at a time so that he could record his dreams. He had three dozen ways of describing the act of urination. At his most prolific, he wrote three million words a year.

Now the Rev Robert Shields has died, aged 89, leaving a 37.5 million-word document that fills 91 boxes.

Monty Shields, 78, told The Times that his brother’s writing was helped by their father being the 1904 world champion in speed typing. “He did not spend as much time on it as you might think because he could type very fast and think very quickly and practically had a photographic memory.”

Mr Shields, a Protestant minister and teacher, died of a heart attack on October 15 at his home in Washington state. He had hoped that future historians would find his diary valuable.

He once told an interviewer: “Maybe by looking into someone’s life at that depth, every minute of every day, they will find out something about all people. I don’t know. No way to tell.”

His diary is almost 30 times longer than Samuel Pepys’s classic journal of 17th-century London, which runs to 1.25 million words. It far exceeds the colourful 21 million-word diary left by Edward Robb Ellis, an American newspaper reporter who died in 1998, aged 87, after recording his life for 70 years.

Guinness World Records does not record the longest diary, but lists a 91-year chronicle written by Colonel Ernest Loftus in Zimbabwe from 1896 to 1987. Mr Shields first started writing a diary when he was 17 to chronicle a romance, but soon gave up. He did not resume in earnest until he was 54.

He also wrote a book about a robbery that became the basis for Elvis Presley’s first film, Love Me Tender. He wrote in his thermal underwear at a desk surrounded by six electric typewriters, taking turns on each machine.

The journal contains a bewildering array of details, ranging from his blood pressure readings to every piece of junk mail he received. “It is an uninhibited diary,” he once said. “It is spontaneous. I type it as it comes and I don’t correct it and I don’t edit it.”

He had to stop typing in 1996 when he suffered a disabling second stroke; his wife soon tired of taking dictation. He donated his diary to Washington State University in 1999 on condition that it will not be read for 50 years. “Some people would say ‘Well, he’s a nut’,” he said in 1995. “Maybe I am.”

Dear diary, it’s Sunday, August 13, 1995 . . .

4.15-7.25am I slept for three hours rather soundly.

7.25-7.30 I sprayed, and puddled and piddled and widdled.

7.30-7.35 I fed the long-haired white cat, Ting, with tinned tuna cat food. She ate the tinned food last night that I had set out yesterday.

7.357.40 I peed again and took a methylpred-nisone tablet.

7.40-8.40 I read the Tri-City Herald, published in Kennewick, Washington 99336... Shannon Faulkner is in The Citadel in Charleston, South Carolina, as a cadet, the only time in 152 years that a female has been admitted to the ranks. I think she is a snot . . .

8.40-8.45 I filled the humidifying basin mounted over the Futura baseboard heater.

8.45-9.20 I shaved twice with the Gillette Sensor blade for the fourth? or fifth? time. I shaved my neck behind both ears, and crossways of my cheeks too.

9.20-9.25 I drenched my hair with and plastered it down with a scrub brush.

9.25-9.35 I dressed in a pair of black Haband trousers, a Haband white mesh shirt, the Haband blue blazer with simulated silver buttons, eyeglasses, the 14-degree Masonic ring, both hearing aids.

9.35-9.40 I cleaned the cerumen from both my ears and from both hearing aids.

9.40-9.55 I hunted high and low for the recent issues of Time and Newsweek to give to the Seneys, and I was frustrated not to find them

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