Six social entrepreneurs - creative people using their talents to rejuvenate their local communities - tell their stories. 4: The Doctor and the Nightingale. When DrTiarks first moved to the small isles off the west coast of Scotland, he knew he had a problem on his hands. His patients were spread out on the four islands of Rum, Muck, Canna and Eigg. How was he going to reach them? Dilly Barlow investigates. Producer Sara Jane Hall