AN AUDIO book charity which helps hundreds of Bucks residents who are unable to read celebrated its 40th anniversary this week.

The county's deputy lieutenant Amanda Nicholson was among the guests invited along by the Calibre Audio Library, which has thousands of members nationwide.

Party attendees took away a special 40th Anniversary CD which told the history of Calibre, with one of the highlights being David Cameron and his MPs recording children’s stories at the 2011 Conservative Party conference.

Chesham and Amersham MP Cheryl Gillan featured on the recording, reading Jacqueline Wilson’s The Mum-Minder from Funny Stories for Seven Year Olds.

Calibre chairman Ian Yeoman, from Chalfont St Giles, said: "It is thanks to all our 200 volunteers and staff that Calibre’s service helped over 18,000 people to enjoy the pleasure of reading last year, sending out over 400,000 audio books - that’s an incredible 200 books per hour.

"Calibre remains unique in offering a subscription-free service to individual members with sight problems, dyslexia or other disabilities which prevent them reading normal print."

Recordings started in 1974 when Monica McMullen, Ros Thornton and Susan Beazley read and recorded LM Mitchell’s Anne of Green Gables for Susan’s partially-sighted son, James.

They used the most modern technology of the time - a cassette recorder - from where the name Calibre is derived.

In the early days just one sack of books a day was sent out - now 1,800 books are despatched to tens of thousands of members nationwide.