There for a time he leaned against a high boulder, idly watching a few sheep nibbling the short grass which grew about some of the many caves which opened in slits or wide hollows. Below and beyond he saw the pale blue silence of the sea meet the pale blue silence of the sky; south-westward, the grey film of the coast of Ulster; westward, again the illimitable vast of sea and sky, infinitudes of calm, as though the blue silence of heaven breathed in that one motionless wave, as though that wave sighed and drew the horizons to its heart. From where he stood he could hear the murmur of the surge whispering all round the isle; the surge that, even on days of profound stillness, makes a murmurous rumour among the rocks and shingle of the island shores. Not upon the moor-side, but in the blank hollows of the caves around him, he heard, as in gigantic shells, the moving of a strange and solemn rhythm: wave-haunted shells indeed, for the echo that was bruited from one to the other came from beneath, from out of those labyrinthine passages and dim, shadowy sea-arcades, where among the melancholy green glooms the Atlantic waters lose themselves in a vain wandering.
For long he leaned there, revolving in his mind the mystery of Morag MacNeill's words. Then, abruptly, the stillness was broken by the sound of a dislodged stone. So little did he expect the foot of fellow-man, that he did not turn at what he thought to be the slip of a sheep. But when upon the slope of the grass, a little way beyond where he stood, a dusky blue shadow wavered fantastically, he swung round with a sudden instinct of dread.
And this was the dread which, after these long weeks since he had come to Rona, was upon Alan Carmichael.
For there, standing quietly by another boulder, at the mouth of another cave, was a man in all appearance identical with himself. Looking at this apparition, he beheld one of the same height as himself, with hair of the same hue, with eyes the same and features the same, with the same carriage, the same smile, the same expression. No, there, and there alone, was any difference.
Sick at heart, Alan wondered if he looked upon his own wraith. Familiar with the legends of his people, it would have been no strange thing to him that there, upon the hillside, should appear the wraith of himself. Had not old Ian McIain—and that, too, though far away in a strange land—seen the death of his mother moving upward from her feet to her knees, from her knees to her waist, from her waist to her neck, and, just before the end, how the shroud darkened along the face until it hid the eyes? Had he not often heard from her, from Ian, of the second self which so often appears beside the living when already the shadow of doom is upon him whose hours are numbered? Was this, then, the reason of what had been his inexplicable gloom? Was he indeed at the extreme of life? Was his soul amid shallows, already a rock upon a blank, inhospitable shore? If not, who or what was this second self which leaned there negligently, looking at him with scornful smiling lips, but with intent, unsmiling eyes.
Slowly there came into his mind this thought: How could a phantom, that was itself intangible, throw a shadow upon the grass, as though it were a living body? Sure, a shadow there was indeed. It lay between the apparition and himself. A legend heard in boyhood came back to him; instinctively he stooped and lifted a stone and flung it midway into the shadow.
"Go back into the darkness," he cried, "if out of the darkness you came; but if you be a living thing, put out your hands!"
The shadow remained motionless. When Alan looked again at his second self, he saw that the scorn which had been upon the lips was now in the eyes also. Ay, for sure, scornful silent laughter it was that lay in those cold wells of light. No phantom that; a man he, even as Alan himself. His heart pulsed like that of a trapped bird, but with the spoken word his courage came back to him.
"Who are you?" he asked, in a voice strange even in his own ears.
"Am Buachaill," replied the man in a voice as low and strange. "I am the Herdsman."