But in that very solitude Alan found healing. From what Giorsal hinted, he came to believe that the fishermen had experienced one of those strange dream-waves which, in remote isles, occur at times, when whole communities will be wrought by the self-same fantasy. When day by day went past, and no one came near, he at first was puzzled, and even resentful; but this passed, and soon he was glad to be alone. Ian, however, knew that there was another cause for the inexplicable aversion that had been shown. But he was silent, and kept a patient watch for the hour that the future held in its shroud. As for Giorsal, she was dumb; but no more looked at Alan askance. And so the weeks went. Occasionally a fishing smack came with the provisions, for the weekly despatch of which Alan had arranged at Loch Boisdale, and sometimes the Barra men put in at the haven, though they would never stay long, and always avoided Alan as much as was possible. In that time Alan and Ian came to know and love their strangely beautiful island home. Hours and hours at a time they spent exploring the dim, green, winding sea-galleries, till at last they knew the chief arcades thoroughly. They had even ventured into some of the narrow, snake-like inner passages, but never for long, because of the awe and dread these held, silent estuaries of the grave. Week after week passed, and to Alan it was as the going of the grey owl's wing, swift and silent. Then it was that, on a day of the days, he was suddenly stricken with a new and startling dread. II In the hour that this terror came upon him Alan was alone upon the high slopes of Rona, where the grass fails and the lichen yellows at close on a thousand feet above the sea. The day had been cloudless since sunrise. The sea was as the single vast petal of an azure flower, all of one unbroken blue save for the shadows of the scattered isles and the slow-drifting mauve or purple of floating weed. Countless birds congregated from every quarter. Guillemots and puffins, cormorants and northern divers, everywhere darted, swam, or slept upon the listless ocean, whose deep breathing no more than lifted a league-long calm here and there, to lapse breathlike as it rose. Through the not less silent quietudes of air the grey skuas swept with curving flight, and the narrow-winged terns made a constant white shimmer. At remote altitudes the gannet motionlessly drifted. Oceanward the great widths of calm were rent now and again by the shoulders of the porpoises which followed the herring trail, their huge, black, revolving bodies looming large above the silent wave. Not a boat was visible anywhere; not even upon the most distant horizons did a brown sail fleck itself duskily against the skyward wall of steely blue.