The pivot of an island's history - the Norman Conquest - turned a land around to face another way, and everything was changed, or changing, in a flash of time. Language and coinage, clothing, cut of hair, the ownership of land, titles and laws - nothing too small, nothing too great, to change. So chroniclers in abbeys and in courts made record of the day. For humbler folk in every family, remembrance paused upon that day, the day that Harold fell, and William was the Conqueror, so named. Later, the new land-owners paid new tax written in Domesday Book. The churches' tithes were penned painstakingly in Latin script. After nine centuries, how few remain! But in a French cathedral, reverently, visitors pass in hundreds to survey the Bayeux Tapestry, a narrow strip of linen and embroidery. The whole battle is there before us. How they must have smiled indulgently, the warrior husbands, fingering the work of Queen Matilda and her ladies remembering the great day. They told their wives, ''Yes, yes, a worthy bit of needlework.'' And to each other, kindly, ''Really good, but such a fragile thing, threads laid on threads.'' And then with tolerant shrug, ''Well, women's work; it serves to pass the time.'' Now, time has passed.