"At a short distance from the hut-dwellings above described is the Bosphrennis cromlech, now fallen. ‘It consisted of four supporters, three feet six inches high, forming a complete kistvaen six feet by three; and what is very remarkable, the covering stone is circular, measuring four feet ten inches in diameter and five inches thick. The stone must certainly have been wrought into this form, and it seems to afford the only known instance of the kind.’ (Blight.) This seems to be the cromlech referred to by Courtney."
taken from West Penwith Resources ( http://west-penwith.org.uk/matthews4.htm )
For a placename Penwith is very close to Penrith - I'll post a picture of my little round rock in situ, at Whitlow, Kirkhaugh, soon. Ideally I'd like someone to take it on a journey to Men-an-Tol and to see what happens when the hole is closed by it. John Edgar, the farmer that owns the stone, would probably agree. I did tell him the archaeologists would come and 'see him right'. There's been no sign of them so far. It must be that name - Smallhenge - putting them off. At least it's not Smallshenge !
david