While Oona was standing on the verge of these mysteries a trial of a very different kind had fallen to Walter. They had exchanged parts in this beginning of their union. It was his to lead the two elder ladies into those rooms which were to him connected with the most painful moments of his life, but to them conveyed no idea beyond the matter of fact that they were more comfortably furnished and inhabitable than was to be expected in such a ruin. Even to Mrs. Methven, who was interrogating his looks all the time, in an anxious endeavour to know what his feelings were, there seemed nothing extraordinary in the place save this. She seated herself calmly in the chair, which he had seen occupied by so different a tenant, and looking smiling towards him, though always with a question in her eyes, began to express her wonder why, with Auchnasheen so near, it had been thought necessary to retain a dwelling-place among these ruins; but since Walter did from time to time inhabit them, his mother found it pleasant that they were so habitable, so almost comfortable, and answered old Macalister's apologies for the want of a fire or any preparations for their coming with smiling assurances that all was very well, that she could not have hoped to find rooms in such careful repair. Mrs. Forrester was a great deal more effusive, and examined everything with a flow of cheerful remark, divided between Lord Erradeen and his old servant, with whom, as with everybody on the loch, she had the acquaintance of a lifetime.

"I must see your wife, Macalister," she said, "and make her my compliment on the way she has kept everything. It is really just a triumph, and I would like to know how she has done it. To keep down the damp even in my little house, where there are always fires going, and every room full, is a constant thought—and how she does it here, where it is so seldom occupied——. The rooms are just wonderfully nice rooms, Lord Erradeen, but I would not say they were a cheerful dwelling—above all, for a young man like you."

"No, they are not a very cheerful dwelling," said Walter with a smile, which to his mother, watching him so closely, told a tale of pain which she did not understand indeed, yet entered into with instinctive sympathy. The place began to breathe out suffering and mystery to her, she could not tell why. It was cold, both in reality and sentiment, the light coming into it from the cold north-east, from the mountains which stood up dark and chill above the low shining of the setting sun. And the cold affected her from his eyes, and made her shiver.

"I think," she said, "we must not stay too long. The sun is getting low, and the cold——"

"But where is Oona?" said Mrs. Forrester. "I would not like to go away till she has had the pleasure too. Oh, yes, it is a pleasure, Lord Erradeen—for you see we cannot look out at our own door, without the sight of your old castle before our eyes, and it is a satisfaction to know what there is within. She must have stayed outside among the rains that she was always partial to. Perhaps Macalister will go and look for her—or, oh! Lord Erradeen, but I could not ask you to take that trouble."

"My lord," said old Macalister aside, "if it had been any other young lady I wad have been after her before now. Miss Oona is just wonderful for sense and judgment; but when I think upon yon wall——"

"I will go," said Walter. Amid all the associations of this place, the thought of Oona had threaded through every movement of his mind. He thought now that she had stayed behind out of sympathy, now that it was indifference, now—he could not tell what to think. But no alarm for her safety had crossed his thoughts. He made a rapid step towards the door, then paused, with a bewildering sense that he was leaving two innocent women without protection in a place full of dangers which they knew nothing of. Was it possible that his enemy could assail him through these unsuspecting simple visitors? He turned back to them with a strange pang of pity and regret, which he himself did not understand. "Mother," he said, "you will forgive me—it is only for a moment?"

"Walter!" she cried, full of surprise; then waved her hand to him with a smile, bidding him, "Go, go—and bring Miss Forrester." Her attitude, her smile of perfect security and pleasure, went with him like a little picture, as he went down the spiral stairs. Mrs. Forrester was in the scene too, in all her pretty faded colour and animation, begging him—"Dear me, not to take the trouble; for no doubt Oona was just at the door, or among the ruins, or saying a word to Hamish about the boat." A peaceful little picture—no shadow upon it; the light a little cold, but the atmosphere so serene and still. Strange contrast to all that he had seen there—the conflict, the anguish, which seemed to have left their traces upon the very walls.

He hurried down-stairs with this in his mind, and a lingering of all his thoughts upon the wistful smiling of his mother's face—though why at this moment he should dwell upon that was a wonder to himself. Oona was not on the grassy slope before the door, nor talking to Hamish at the landing-place, as her mother suggested. There was no trace of her among the ruins. Then, but not till then, Walter began to feel a tremor of alarm. There came suddenly into his mind the recollection of that catastrophe of which he had been told in Edinburgh by its victim; it sent a shiver through him, but even yet he did not seriously fear; for Oona was no stranger to lose herself upon the dangerous places of the ruin. He went hurriedly up the steps to the battlements, where he himself had passed through so many internal struggles, thinking nothing less than to find her in one of the embrasures, where he had sat and looked out upon the loch. He had been startled as he came out of the shadow of the house, by a faint cry, which seemed to issue from the distance, from the other extremity of the water, and which was indeed the cry for help to which Oona had given utterance when she felt the wall crumbling under her feet, which the wind had carried far down the loch, and which came back in a distant echo. Walter began to remember this cry as he searched in vain for any trace of her. And when he reached the spot where the danger began and saw the traces that some other steps had been there before him, and that a shower of crumbling mortar and fragments of stone had fallen, his heart leaped to his throat with sudden horror. This was calmed by the instant reassurance that had she fallen he must at once have discovered the catastrophe. He looked round him bewildered, unable to conceive what had become of her. Where had she gone? The boat lay at the landing-place, with Hamish in waiting; the whole scene full of rest and calm, and everything silent about and around. "Oona!" he cried, but the wind caught his voice too, and carried it away to the village on the other bank, to her own isle away upon the glistening water, where Oona was not. Where was she? His throat began to grow parched, his breath to labour with the hurry of his heart. He stood on the verge of the precipice of broken masonry, straining his eyes over the stony pinnacles above, and the sharp irregularities of the ruin. There he saw something suddenly which made his heart stand still: her glove lying where she had dropped it in her hurried progress along the ledge. He did not pause to think how she got there, which would have seemed at another moment impossible, but with a desperate spring and a sensation as of death in his heart, followed, where she had passed, wherever that might be.

Walter neither knew where he was going nor how he made his way along those jagged heights. He did not go cautiously as Oona had done, but flew on, taking no notice of the dangers of the way. The sound of voices, and of his own name, and Oona's cry for help, reached his ear as with a leap he gained the stone balcony of the tower. His feet scarcely touched the stones as he flew to her who called him, nor did he think where he was, or feel any wonder at the call, or at the voices on such a height, or at anything that was happening. His mind had no room for any observation or thought save that Oona called him. He flung himself into the dark doorway as if it had been a place he had known all his life, and caught her as her strength failed her. She who had thought she could put herself in his place, and who had been ready to brave everything for him, turned round with her eyes glazing and her limbs giving way, with strength enough only to throw herself upon his breast. Thus Walter found himself once more face to face with his enemy. The last time they had met, Lord Erradeen had been goaded almost to madness. He stood now supporting Oona on his arm, stern, threatening in his turn.

"If you have killed her," he cried; "if you have hurt her as you did before; if you have made her your victim, as you did before!" There was no shrinking in his look now: he spoke out loudly with his head high, his eyes blazing upon the enemy who was no longer his, but hers, which had a very different meaning; and though he stood against the door where he had found Oona holding it wide open, this was done unconsciously, with no idea of precaution. The time for that was over now.

And with the sensation of his support, the throb of his heart so near hers, Oona came back to herself. She turned slowly round towards the inhabitant of the tower. "Walter, tell him—that though he can make us miserable he cannot make us consent. Tell him—that now we are two, not one, and that our life is ours, not his. Oh!" she cried, lifting her eyes, addressing herself directly to him, "listen to me!—over me you have no power—and Walter is mine, and I am his. Go—leave us in peace."

"She says true; leave us in peace. In all my life now, I shall do no act that is not half hers, and over her you have no power."

"You expect me then," he said, "to give way to this bargain of self-interest—a partnership of protection to you and gain to her. And you think that before this I am to give way."

"It is not so," cried Walter, "not so. Oona, answer him. I turned to her for help because I loved her, and she to me for—I know not why—because she loved me. Answer him, Oona! if it should be at this moment for death not for life—"

She turned to him with a look and a smile, and put her arm through his, clasping his hand: then turned again to the other who stood looking on. "If it should be for death," she said.

There was a moment of intense stillness. He before whom these two stood knew human nature well. He knew every way in which to work upon a solitary being, a soul alone, in his power; but he knew that before two, awake, alive, on the watch one for the other, these methods were without power, and though his experiences were so great the situation was new. They were in the first absolute devotion of their union, invulnerable, no germ of distrust, no crevice of possible separation. He might kill, but he could not move them. This mysterious agent was not above the artifices of defeat. To separate them was the only device that remained to him.

"You are aware," he said, "that here if nowhere else you are absolutely in my power. You have come to me. I have not gone to you. If you wish to sacrifice her life you can do so, but what right have you to do it? How dare you take her from those who love her, and make her your victim? She will be your victim, not mine. There is time yet for her to escape. It is for her to go—Die? why should she die? Are you worth such a sacrifice? Let her go——"

"Hold me fast—do not loose me, Walter," cried Oona wildly in his ear.

And here his last temptation took him, in the guise of love, and rent him in two. To let her perish, was that possible? Could he hold her though she was his life, and sacrifice hers? Walter could not pause to think; he tore his hand out of hers, which would not be loosed, and thrust her from him. "Oona," he cried, his voice sinking to a whisper, "go! Oona, go! Not to sacrifice you—no, no, I will not. Anything but that. While there is time, go!"

She stood for a moment between the two, deserted, cast off by him who loved her. It was the supreme crisis of all this story of her heart. For a moment she said nothing, but looked at them, meeting the keen gaze of the tempter, whose eyes seemed to burn her, gazing at Walter who had half-closed his not to see her go. Then with the sudden, swift, passionate action, unpremeditated and impulsive, which is natural to women, she flung herself before him, and seized with her hands the table upon which the light was burning. "You said," she cried, breathless, "that you used small methods as well as great—and this is one, whatever it is." She thrust it from her violently as she spoke. The lamp fell with a great crash and broke, and the liquid which had supplied it burst out and ran blazing in great globules of flames over the floor. The crash, the blaze, the sudden uproar, was like a wall between the antagonists. The curtains swaying with the wind, the old dry tapestries, caught in the fire like tinder. Oona, as wild with fear as she had been with daring, caught at Walter's hand with the strength of despair, and fled dragging him after her. The door clanged behind them as he let it go, then burst open again with the force of the breeze and let out a great blaze, the red mad gleam of fire in the sunshine and daylight—unnatural, devouring. With a sense that death was in their way before and behind, they went forth clinging to each other, half-stupefied, half-desperate. Then sense and hearing and consciousness itself were lost in a roar as of all the elements let loose—a great dizzy upheaving as of an earthquake. The whole world darkened round them; there was a sudden rush of air and whirl of giddy sensation—and nothing more.

The two mothers meanwhile talked calmly in the room below, where Macalister had lighted the fire, and where, in the cheerful blaze and glow, everything became more easy and tranquil and calm. Perhaps even the absence of the young pair, whose high strain of existence at the moment could not but disturb the elder souls with sympathy, made the quiet waiting, the pleasant talk, more natural. Mrs. Methven had been deeply touched by her son's all unneeded apology for leaving her. She could have laughed over it, and cried, it was so kind, so tender of Walter, yet unlike him, the late awakening of thought and tenderness to which she had never been accustomed, which penetrated her with a sweet and delightful amusement as well as happiness. She had no reason to apprehend any evil, neither was Mrs. Forrester afraid for Oona. "Oh no, she is well used to going about by herself. There is nobody near but knows my Oona. Her family and all her belongings have been on the loch, I might say, since ever it was a loch; and if any stranger took it upon him to say an uncivil word, there is neither man nor woman for ten miles round but would stand up for her—if such a thing could be," Mrs. Forrester added with dignity, "which is just impossible and not to be thought of. And as for ruins, she knows them well. But I would like her to see the books, and what a nice room Lord Erradeen has here, for often we have been sorry for him, and wondered what kind of accommodation there was, and what good it could do to drag the poor young man out of his comfortable house, if it was only once in the year——"

"And why should he come here once in the year?" Mrs. Methven asked with a smile.

"That is just the strange story: but I could not take upon myself to say, for I know nothing except the common talk, which is nonsense, no doubt. You will never have been in the north before?" said Mrs. Forrester, thinking it judicious to change the subject.

"Never before," Mrs. Methven replied, perceiving equally on her side that the secrets of the family were not to be gleaned from a stranger; and she added, "My son himself has not yet seen his other houses, though this is the second time he has come here."

"It is to be hoped," said the other, "that now he will think less of that weary London, which I hear is just an endless traffic of parties and pleasure—and settle down to be a Scots lord. We must make excuses for a young man that naturally likes to be among his own kind, and finds more pleasure in an endless on-going than ladies always understand. Though I will not say but I like society very well myself, and would be proud to see my friends about me, if it were not for the quiet way that Oona and I are living, upon a little bit isle, which makes it always needful to consider the weather, and if there is a moon, and all that; and besides that, I have no gentleman in the house."

"I never had a daughter," said Mrs. Methven; "there can be no companion so sweet."

"You mean Oona? Her and me," said Mrs. Forrester, with Scotch grammar and a smile, "we are but one; and you do not expect me to praise myself? When I say we have no gentleman in the house, it is because we cannot be of the use we would wish to our friends. To offer a cup of tea is just all I have in my power, and that is nothing to ask a gentleman to; but for all that it is wonderful how constantly we are seeing our neighbours, especially in the summer time, when the days are long. But bless me, what is that?" Mrs. Forrester cried. The end of her words was lost in a tumult and horror of sound such as Loch Houran had never heard before.