St. Elidius was Bishop of Llandaff in the sixth century, and during the yellow plague he went to stay in Brittany with his friend St. Sampson, the Bishop of Dol, to whom the neighbouring island of Samson is dedicated. He was in his old age called Elios, “for that his doctrine shone like the sun.” This name, St. Elios, appears to have become, by different stages, St. Teilo, St. Dillo, and St. Dellan, whence it easily passed into St. Helen. Dr. Borlase mentions a church on St. Helen’s as the most ancient Christian building in Scilly. He thus describes it as it stood in 1756:-- “It consists of a South Isle, 31 feet 6 inches long, by 14 feet 3 inches wide, from which two arches, low and of uncouth style, open into a North Isle, 12 feet wide by 19 feet 6 inches long. There are two windows in each Isle; near the Eastern window in the North Isle projects a flat stone, to support, I suppose, the image of the saint.” Little but the foundations of the church can now be traced, which is all the more to be regretted, since it probably dated back to the eighth century, or earlier. Many of the stones were taken away early in the last century, to build a garden wall for a naval officer stationed in the island. St. Helen’s Pool was appointed the quarantine station in 1756. The Council of Scilly had appealed two years before that it might be made so, in the stead of New Grimsby Sound, where the presence of infected persons was a great source of danger to the inhabitants of Tresco and Bryher. The Pesthouse on St. Helen’s, standing deep in bracken, is now in a state of ruin, and it is hardly safe to enter on account of the falling of slates through holes in the roof. It seems a gruesome sort of place to have been used by picnic-parties, but in its better days, we are told, they often boiled their kettles in the hospital ward! Rats abound on St. Helen’s, as a foolish pair of honeymooners discovered when they went to spend the night there a short time ago. In the morning they found their basket of provisions had been quite emptied by the rats, “and it’s a wonder the rats had not eaten them up too,” said she who told the tale. [Illustration: ROUND ISLAND, FROM ST. HELEN’S] Not far from the Pest-house there is a deep well of water; and the surface of the island is scattered thick with limpet-shells--two facts which may seem to have little connection, but which I have reason to associate. We had come to St. Helen’s by sailing-boat, and I was preparing to sketch Round Island from the northern shore when I found my water-bottle was empty. This was a great damper, for the water in the old well was much too far down to be reached without a rope. But we happened to notice the limpet-shells. There had been a heavy shower in the night, and every little shell was brimful of rain-water, so by collecting a number of them and straining out the dead ants, my wants were easily supplied.