There might be a number of stones around here (the area is awash in barrows and mounds) - I hope this map reference is helpful. This sarsen (or is it a deliberately placed stone?) is near to Luccombe Springs. Katy Jordan (in The Haunted Landscape) tells of a conversation she had with a local woman, Jean Morrison. Apparently if you hold your breath and run round the stone 9 times, backwards, the devil will appear. Brave Jean had tried it as a child but alas was unable to hold her breath for so long.
Could this refer to the same stone? The area sounds convincingly between Bratton and Edington.
The following occurs in a Perambulation of the Hundred and Parish of Westbury, temp. Eliz., 1575:
"And so by a straight line between Eddington Field and Bretton's Field to a stone called 'Patten's Stone' (anciently Padcanstone; and so straight along the way to a little ball where once was a stone cross, called Lealland Cross, standing on the highway between Devizes and Warminster."
A contribution on p278 of Wiltshire Notes and Queries, June 1894.
David Stokes' comprehensive webpage has masses of information about the local area and its legendary? historical? site of the battle of Ethandun. He mentions that he played at the stone as a child: he knew that it was stained red, from all the Danes that were beheaded there.
He says it is a different rock to any found locally: I have tentatively changed the category from 'natural rock feature' to 'standing stone' to reflect this.