Fireman David Thomas is attempting the world's most challenging memory feat to secure a place in the Guinness Book of Records.

In May he plans to reel off 30,000 numbers - based on the mathematical formula Pi - in the correct order in 12 hours.

And if he is successful he plans to attempt 50,000 digits later in the year to break the world record.

The current British record is 20,013 numbers, achieved by Creighton Carvello from Middlesbrough in just over nine hours. The world record of 42,195 is held by Hideaki Tomoyori from Japan. It took him 11 hours.

David, 29, of Whinney Hill Park, Brighouse, who runs his own memory teaching business, came third in the World Memory Championships in London last year and fourth the previous year at his first attempt.

He is also an International Grand Master of Memory - one of only four people in the world who hold that honour - after completing tasks involving packs of cards and numbers.

David, a full-time fireman at Elland fire station, said: "My latest attempt is regarded internationally as the most difficult memory feat of all. People all over the world have tried it and failed. It is physically demanding and requires 100 per cent concentration. I would literally only have to lose my concentration for one second and I would be out.

"Remembering the numbers in the right order will not be the problem on the day, but making sure I do not make a verbal error as I am saying the numbers to the invigilator. One mistake and I've lost.

"I hope to have a break every three hours for no more than 15 minutes on the day which means I will have to remember exactly where I left off in between each stint.''

He is now limbering up for his memory marathon with the help of his partner Julie Holdsworth, 34, who helps him prepare for all his challenges.

David said: "At the moment I am spending 20 hours a week memorising the numbers, but this will go up to 50 hours a week when I am on annual leave at the beginning of April.

"Julie has the boring task of ticking the numbers off sheets as I say them. We do one to two hour stints at a time.''

Mother-of-two Julie, who is studying to be a counsellor, said: "I have to have complete concentration while David is reciting the numbers back to me. It's hard work but exciting because I want him to succeed.''

David become hooked on his painstaking hobby four years ago after watching a man on TV memorise a pack of cards in seconds and made it look so easy. He said: "I was gripped by what he did.

"Some people have said a good memory is like magic, but unlike a magician who gives the illusion of pulling a rabbit out of a hat, this man actually did perform with the pack of cards for real.

"I went out and bought a book on memory written by this man and taught myself.

"Until then, like many people, I had a poor memory capability.

"Anybody can have a good memory. It's all about technique. And your memory becomes stronger the more you use the technique.

"I have to use the technique to remember things like birthdays and phone numbers, otherwise I would forget."

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