Back in 1970 or very early 80s there was a series about a time traveller. Possibly a BBC kids drama. The heroine was called Ariadne and it was set around the time of abolition of slavery. There was a black African boy who she helps to escape his owner who lives in a big house . The finale was the time traveller went back to her own time and the real Ariadne had died of Typhoid on the journey and had never really arrived at the grand house. Anyone any ideas??