Rosslyn Chapel was built in the 15th Century

Stuart Mitchell, 41 and his father Tommy, 75, said they had deciphered a musical code locked in the stones of Rosslyn Chapel for more than 500 years.

They will perform the music in May at a concert in the 15th Century chapel.

Visitor numbers to the chapel have increased rapidly since it featured in Dan Brown's novel The Da Vinci Code.

Stuart Mitchell discovered a series of figures which he calls an "orchestra of angels" at the base of elaborate arches round the altar, with each angel holding a musical instrument.

He worked with his father to decipher the patterns on cubes which jut out from the arches.

Over the years this became more of an obsession than anything else and we decided we had to find out what was going on

Tommy Mitchell

Tommy Mitchell said the markings concealed a tune which they were determined to crack.

He said: "We were convinced from the position at the top of the pillars of the angels and they are all directly under the arches where the cubes occur that there was music there.

"We got clues from other books as well. Over the years this became more of an obsession than anything else and we decided we had to find out what was going on."

"If these patterns and cubes had not contained music anything we turned up would have been purely random and would not have sounded hauntily beautiful."

Stuart Mitchell said the tunes could have been hidden because knowledge of harmonics may have been seen as dangerous, even heretical, by 15th Century church authorities.

He said: "What we have here is a recorded piece of music, it is almost like a compact disc from the 15th Century."

Your comments

Music, like mathematics, is based on patterns. Mr and Master Mitchell are free to translate patterns into music, though the harmonious proportions they have found in the architecture of Rosslyn Chapel are no more significant than those found in a '50s high rise. Perhaps the magnificent symmetries of the Forth Bridge will provide the inspiration for their next opus.

Jim, London

Yes I think this is very possible with the use of cymatics which shows the shapes created by notes of sound. Whether the code was hidden there intentionally I'm not sure, it will depend on how the piece of music comes out.

Hannah Ireland, Shoreham-by-Sea, West Sussex

It will be very interesting to see how the code has been translated into the exact musical notes, and what decisions have been made about musical scale and modality. The snippet of the motet sound clip suggests melodic and harmonic characteristics of a later period.

Paul, W. Yorkshire