Neolithic engineers may have used ball bearings in the construction of Stonehenge, it was claimed today.
The same technique that allows vehicles and machinery to run smoothly today could have been used to transport the monument's massive standing stones more than 4,000 years ago, according to a new theory.
Scientists showed how balls placed in grooved wooden tracks would have allowed the easy movement of stones weighing many tons.
No-one has yet successfully explained how the heavy slabs used to build Stonehenge were shifted from their quarries to Salisbury Plain in Wiltshire
Some, the 'bluestones', weighed four tons each and were brought a distance of 150 miles from Pembrokeshire, Wales.
Attempts to re-enact transporting the blocks on wooden rollers or floating them on the sea have not proved convincing.
The hard surfaces and trenches needed when using rollers would also have left their mark on the landscape, but are missing.
Experts hit on the new idea after examining mysterious stone balls found near Stonehenge-like monuments in Aberdeenshire, Scotland.
About the size of a cricket ball, they are precisely fashioned to be within a millimetre of the same size.
This suggests they were meant to be used together in some way rather than individually.
The Scottish stone circles are similar in form to Stonehenge, but contain some much larger stones.
To test the theory, researchers from the University of Exeter constructed a model in which wooden balls were inserted into grooves dug out of timber planks.
When heavy concrete slabs were placed on a platform above the balls, held in position by more grooved tracks, they could be moved with ease.
Archaeologist Andrew Young described the experiment in which he sat on top of the slabs to provide extra weight.
He said: 'The true test was when a colleague used his index finger to move me forward - a mere push and the slabs and I shot forward.
'This proved the balls could move large heavy objects and could be a viable explanation of how giant stones were moved.' ...
via Stonehenge builders 'used ball bearings to move giant slabs of stone' | Mail Online.