Standing quietly in the middle of the room, all was still and calm concerning the general atmosphere.  There came over me a sensation of controlling power which first turned my head from side to side without any conscious effort on my part.  Then with an overwhelming power my body was rotated and forced in a backward direction.  I grabbed a piece of furniture to steady myself and the power dissipated.  I stood once more in the centre of the room and exactly the same experience occurred.  I decided enough was enough and quickly left the room.