Beyond the barrier reef formed by the Outer Hebrides lies a scattering of small islands that rarely appear on a map of Britain but are, nevertheless, British Isles. Some, like Flannan and Rona, have been inhabited by devout hermits but there are some, without fresh water or soil sufficient to grow the poorest of food, that would have tried the patience of a saint. Such an island is Sula Sgeir, Gannet Rock, little more than half a mile long and at its narrowest point only a few yards wide. In addition, it is surrounded by precipitous rocks and the most dangerous waters in the northern hemisphere. Surely the combined threat of drowning and drought must have deterred even the most hardy. But history says not. In the twelfth century, Bruinhilda, a holy sister of the chapel on nearby St Ronan, must have felt the worldly temptations (e.g. running water) of her mother church to be too great and so repaired to Sula. Here she built Tigh Beannaichte, the blessed house, where she lived and died with only the seabirds as witness.

Nor was she the only visitor to spend time on the rock. From time immemorial, ten men from Ness in the north of Lewis have set sail to the island and once a year ten men still do. It was a great honour to be one of the chosen and the position is handed down from father to son. Until recent times, the forty-mile journey would have been made in an open boat and without a compass. One degree out and the next stop was Greenland. Today, the group hire a trawler to drop them off and, if the weather holds, to pick them up again. But the reason is the same — they are there to harvest the guga, or the young, of the North Atlantic gannet. Even when an act of Parliament protected the bird against human predators, an exception was made for the men of Ness and each year, taking advantage of the best of the bad weather, they leave for Sula to kill and cure their allocation of 2000 young birds.