Stonehenge rings a bell
BEFORE dawn on Saturday, thousands of revellers will again gather among the monoliths at Stonehenge to sing, bang drums and frolic beneath a solstice sunrise.
Theories surrounding the monument's intended purpose - temple? observatory? big sundial? - go in and out of fashion.
But this year, the partygoers will show up outside Salisbury with fresh evidence that the site was always intended to host such shenanigans.
Specifically, making loud rock music.
Researchers from the Royal College of Art in London have found that some of the monument's rocks possess unusual acoustic properties; when struck, they make a loud, clanging noise.
Perhaps, they say, this explains why these particular rocks were chosen and hauled from nearly 250km away - a significant technical feat some 4,000 years ago.
Could it be that Stonehenge was actually a prehistoric glockenspiel?
"People say, 'Why did they bring the bluestones to Stonehenge?'" said Paul Devereux, an author of the study and editor of the journal that published it, Time And Mind: The Journal Of Archaeology, Consciousness And Culture.
"Bluestone" is a British term for the 35 or so shorter rocks hauled to the site.
Indeed, scientists have long known that many of the Stonehenge rocks were taken from the Preseli Hills, in West Wales. What was never clear is why.
"Rocks are all over the place," he added. "You don't have to cart them 160 miles (about 250km)."
The idea that these rocks were used for making music - or noise, at least - came to Mr Devereux and his colleague, Jon Wozencroft, a lecturer at the Royal College of Art, during a field trip to Preseli.
As art instructors, they were looking to cure students of their dependence on digital material by exposing them to "what Stone Age eyes and ears" once perceived, the study said.
They found that in some areas of Preseli, a grey or black intrusive igneous rock known as diabase or dolerite, one of the types found at Stonehenge, produced a sound like a metallic bell when struck.
Because the Stonehenge bluestones are set into the ground, some shored up with concrete, the researchers' expectations were not high.
"There has to be some airspace around them for the resonance to take place," Mr Devereux said. Still, several of the rocks clearly produced hollow, bell-like noises. And some of those appeared to bear the scars of being struck.
Among ancient cultures, ringing rocks were sometimes thought to be imbued with mystical or healing powers.
The Chinese believed the stones that they called bayinshi, or "resonant rocks", contained a life force known as chi.
Neolithic art has been found on ringing rocks in India, and some Native American rituals are known to have involved such rocks.
These associations may explain what ringing rocks, also known as lithophones, are doing at Stonehenge, a site long associated with rituals.