March 6, 2014
Were Stonehenge’s Bluestones Chosen For Their Acoustic Properties?
Lawrence LeBlond for redOrbit.com - Your Universe Online
It has been a long-standing mystery as to how and why the giant “Preseli” bluestones from southwest Wales ended up nearly 200 miles away at Stonehenge. While a number of theories persist on how they got there, there isn’t much in the way of why.
Researchers from the Royal College of Art in London now think they have that answer. In a recent study, published in the Journal of Time & Mind, the team reports that these giant stones may have been chosen for their unique acoustic properties, possibly making Stonehenge a prehistoric amphitheater.
The study, which was released in December, shortly before the opening of the new Stonehenge Visitor Center, was conducted as part of the College’s Landscape & Perception Project (L&P), which itself is a study of the visual and acoustic elements of the landscape on and around Pembrokeshire, areas where most of the bluestones originated.
Jon Wozencroft, a sound specialist at RCA, and ‘archeo-acoustic’ expert Paul Devereux, along with a diverse team of scientists from several fields and from several different institutions, took on a study to demonstrate to design students how direct sensory material for their digital work can be used – by incorporating sights and sounds of the Stone Age.
It was during this study that the team uncovered the fact that the area where the Stonehenge bluestones derived was a natural soundscape. Knowing this led the team to surmise that the bluestones were taken from this area with this prehistoric acoustic knowledge in mind – a knowledge that could have a greater understanding today of why Stonehenge was built.
Rocks that seem to make music or have sonic capabilities are generally referred to as ‘ringing rocks’ or ‘lithophones.’ A significant amount of the rocks found on Carn Menyn in Pembrokeshire have been found to produce metallic sounds like bells, gongs or tin drums when struck with small hammerstones. The team found an even higher percentage of sonic stones at quarries in the area as well.
Interestingly, the Preseli village of Maenclochog, which itself means ‘ringing stones,’ used bluestones as church bells until the eighteenth century. These lithophones have long been known of and used by peoples of the region and a great number of Neolithic monuments created by lithophones still exist in the region. The new evidence by the L&P team suggests that sounds made the landscape sacred to Stone Age people.
This study is not the first to point to the regions stones as having acoustic properties. British archaeologist Bernard Fagg suspected the rocks around Preseli were of acoustic nature and suggested there was a link between these rocks and the sacred Neolithic monuments and landscapes.
Last July, the L&P team was given unprecedented special access to Stonehenge to test the bluestones. With accompaniment from Bournemouth and Bristol Universities, the team set out to test the acoustic properties of the ancient megaliths.
But because of the way the rocks at Stonehenge were placed – some set deep into the Earth and others supported by concrete – the researchers were not expecting to find much, noting that lithophones require ‘resonant space’ where sound waves have enough room to vibrate to produce pure sounds.
Surprisingly, several of the bluestones at the monument had made distinctive, albeit muted, sounds. The team was sure this was an indication that the rocks would have been fully lithophonic if they had sufficient resonating space. While there also exists evidence that a number of the Stonehenge bluestones have been previously struck, perhaps in order to create an acoustic environment, Wozencroft maintains that more research would be needed to fully understand the nature of the markings on these ancient lithophones.
The team suggests it seems these stones were chosen because of their mystical, musical and perhaps, magical, qualities – there are plentiful rocks around the Salisbury Plain where Stonehenge was erected, yet the bluestones were clearly considered something special in the eyes of the Stone Age people.
While lithophones today are solely considered as melodical curiosities, the peoples of ancient history thought much differently of these stones, based on cross-cultural research. The echoes and sounds made from rocks, cliffs and caves were often deemed as created by spirits trapped with the rocks or other magical forces.
Since, lithophones of the time were held in high regard for their unique properties, it is safe to assume the architects of Stonehenge had similar beliefs.