So runs an old island rhyme, and surely never was there an island so beaten upon and shouted round by the angry tides. It sets a black front of jagged rocks to the Atlantic on the west, and the great billows, rushing on the rocks, send spouts of spray high in the air, to whirl eastward over the gradual slope of the isle. All day long the tide sweeps past on either side, boiling and eddying like a swift and deep river. When the wind is in the north-west and a strong ebb-tide is running, then is the time to see the roosts in all their glory; for the inrolling ocean swell meets the outrushing tide in the narrow channels, and the white waves leap and roar as if some “wallowing monster spouted His foam fountains in the sea.” To see this mad turmoil of the roost on a wild winter day is strange and terrible; but when the white breakers shout and toss themselves in the sunlight of a still June morning there is a paradoxical charm in the sudden outburst of leaping, sparkling foam amid the blue waters, unruffled of any wind, that the wildest storm of winter can never claim. There is an even stronger fascination in the swift, dark, silent rush of the tides, ceaseless along the shores, sweeping in with the flood and whirling out again with the ebb, and with the little green isle in their midst setting its steep front to the angry ocean, but sheltering with its two long eastward points a quiet sandy bay where no current ever comes. All along the coast, on either side of Eynhallow Sound, are low green mounds, marking the places where once were the homes of the prehistoric Orcadians, that Celtic or Pictish race which the conquering Norsemen destroyed so completely that there is not in all the place-names of the isles any trace of their forgotten tongue. Amidst such surroundings, one has only to look at Eynhallow to know that it must have gathered legend and tradition in the long years. In Rousay there still lingers a tale of the breaking of the spell that held Eynhallow sea-bound; for “once upon a time” the isle was enchanted, and visible to human eyes only at rare intervals. It would rise suddenly out of the sea, and vanish as suddenly before any mortal could reach it. And if any one should feel inclined to doubt this tale, can we not point him to the isle of Heather-Bleather, which is still held by the spell of the sea-folk, and appears and disappears even unto this day?