Post by Elly on Jul 6, 2006 3:41:39 GMT 10
Midsummer magic in the ancient stone circles of Orkney
KATH GOURLAY
MIDSUMMER Night's Eve at Orkney's ancient Ring of Brodgar was oppressive and gloomy. When it came to solstice-watching, the wind-driven rain ensured only a few die-hards remained huddled behind the massive sandstone monoliths, struggling to see a man in the centre of the great circle swinging a strip of leather tied round a pebble.
The man – sometimes described as "the real Robert Langdon" – was scientist and writer Dr Robert Lomas, going into prehistoric mode to put his theories about ancient astronomy into practice. He hopes his regular solstice visits to Orkney will eventually prove his theory that a 5,000-year-old system of measurement began in Northern Britain.
Lomas was concentrating on the slow, rhythmic sway of his pendulum, carefully setting down a pebble to mark off each swing.
"It's all based on the positions of the stars and planets," he informs those of us who had ventured beyond the shelter, "and when you live so far north the curvature of the earth is obvious. You can see how the positions alter as the earth spins around the sun."
Lomas believes that by a (very complicated) method of swinging his pendulum and noting the position of the sun, he has found the root of the so-called Megalithic Yard. This measurement, thinks Lomas, was the unit that set the standard for building techniques worldwide – including the pyramids.
"Where we're standing here in Brodgar is basically the first building standards office in the world – no doubt about it. The Megalithic Unit was based on a standard length of 16.32 inches, 41.48 centimetres, if you think metric."
A word of warning here - Lomas's experiments appear somewhat complicated to the uninitiated. Figures and measurements are bandied about and, to be honest, unless you're a sophisticated mathematician it is easy to become lost. Nevertheless, Lomas is passionate about his obsession with plumb lines and monoliths, which he blames on Scots engineer Alexander Thom. During the 1960s, Thom painstakingly measured hundreds of ancient sites which had all used the same standard unit for their building work.
"He died never knowing how they'd done it and nobody believed him, so I took it up as a challenge," says Lomas.
His theories start off reasonably simply, with the daytime star – the sun. You put a big wooden stake in the ground to mark the centre of your circle; then you come out very early each morning to place a marker where its shadow falls as the first beams of sunlight hit it. You do the same every day for a year and when the shadow comes back to where it first started, you have 366 markers forming a circle round the outside.
"Of course it isn't as simple as that," says the Bradford University lecturer. "We know every year doesn't have 366 days, which is why we've got leap years. Of course you can't get a quarter of a sunrise, so the ancients set out a stone to mark each day, and ended up with 366. Although they had no number system, they eventually realised things went out of synch and did some amazing astronomical calculations, using the planet Venus, to regularise it every eight years – but let's not go into that just yet."
Let's not! It's hard enough wondering how the ancients accounted for non-sunny, no-shadow mornings without throwing in complicated astronomical calculations.
Meanwhile Lomas has moved on, connecting daylight calculations with evening ones. He's now working out how long it took for a star to pass between each gap in the stones, although the all-important midsummer alignment is proving problematic to chart because of the cloud cover!
Lomas seems unperturbed. He doggedly keeps swinging his plumb line and adding more pebbles to the ground.
"Way hey!" he shouts eventually.
We move reluctantly from the relative comfort and shelter of a standing stone and take a look.
He's made a line of pebbles.
"Some of the old monoliths are now missing but you can calculate where they all would have been. Mathematically it's perfect - see!"
Well, not really, but then as a physicist and mathematician, Lomas has a bit of a head start on the rest of us. So he tries to explain again.
"You just set down pebbles to mark each beat of your swinging plumb line – a kind of tallying system. You have to adjust the length of the leather thong so that the arc of the swing is just right and corresponds with 366 beats – or pebbles – before the star has passed through one of your 'daily gaps' - that's the magic length of thong – it links the sun and the stars you see."
He smiles patiently.
"That plumb line will measure 16.3 inches if you sit and work out your swing in the middle of any circle divided into 366 sections. It's a mathematical fact. By today's standards you would use computers to achieve the same level of accuracy."
As the sky lightens on the longest day, the rain clears and the first welcoming sunlight casts a shadow from his central stake. Amazingly, it's just slightly off-centre on the monolith he'd based his calculations on last year.
The sensible people have long since headed back to their cars and a warm bed. Few remain to hear Lomas elaborate on how the 2008 leap year will rectify matters.
According to Lomas, the Ring of Brodgar could be the Greenwich Mean Time of Neolithic building techniques.
This article: heritage.scotsman.com/myths.cfm?id=934462006