Clever time-travel novel in which of course the time traveller is not seen as such because that is not a concept known to the people of that day. Although I did wonder about Sarah Blundy's perception of those around her - q.v. when she exposes herself to the priest his reaction is understated if anything, and hardly exposes him as a priest; who says he wants some random woman showing herself to him? Her knowledge of medicine is hardly advanced, more that of someone who is travelling about and needs to know some.