Spinning ice disc phenomenon seen in British river

clipped from www.telegraph.co.uk A rare phenomenon normally associated with Scandinavia has been recorded on the River Otter in Devon such discs were "very, very rare" and he had never heard of one forming in England before. The giant spinning disc of ice slowly rotating ten foot wide and perfectly circular phenomenon which was stationary in the current and about six foot from the bank near where a stream joined the river. "It is thought that they are formed when a slow moving river current creates a slow turning eddy in which a rotating disc of ice grinds out its edges forming a gap between it and the surrounding ice."