Burial chamber reveals haunting sound of past
by John Burns
NEWGRANGE, Ireland's world-renowned, neolithic burial chamber, may have been used as a prehistoric "echo chamber" in religious ceremonies, according to two scientists who have discovered that the 5,000-year-old grave has an ability to alter sound.
While the burial chamber was not designed for that purpose by our neolithic ancestors, they would have inevitably discovered the amazing acoustic effects in Newgrange and exploited them in religious ceremonies, the scientists say.
Aaron Watson, an archeologist, and David Keating, an acoustic expert, carried out up to 10 hours of sound tests at Newgrange last month in conjunction with the BBC. The tests, including humming, bursting balloons, banging drums and playing "standing waves" to the stones, will be broadcast on a Radio 4 documentary next week.
The University of Reading scientists have conducted similar tests at Stonehenge and other neolithic sites.
"We had a loudspeaker making a humming tone and as you moved towards the sound, it got quieter. It was very unusual," said Keating. "However, if you moved away towards the side chambers, the sound got louder. Even with modern knowledge of acoustics, it is quite an eerie and odd effect."
Keating believes neolithic priests or druids may have exploited this phenomenon in ceremonies. "If they were humming in the main chamber, and there was no visible evidence they were making that sound, someone could believe that the noise was coming from the side chambers where the bodies of the dead were buried," he said.
"It is inevitable that priests or druids would have found this effect and exploited it, or it is possible they believed that when they made this noise they were bringing the dead to life."
Keating believes the acoustic tricks may help explain how Newgrange was constructed by such a primitive society. It was built 500 years before the great pyramid of Giza and a millennium before Stonehenge. It was aligned with the winter solstice; only at dawn on December 21* each year does the sun's light pass through a 25cm opening above the entrance.
Watson and Keating found a strange effect from beating drums in the chamber. Inside, the noise is very loud but outside, a listener only hears a distant drum.
Stone Age Sound, the BBC documentary, will be broadcast on July 24 at 11am.
*(Correction by Richard Marsh: The sun enters the chamber through this opening, called the Roofbox, on the mornings of the 19th through the 23rd.)