'_By Jove!_' exclaimed Peter, suddenly starting from his seat. He saw it all in a flash: the burning tower, with volumes of smoke rising from it; the line of men, with hose and buckets, pouring water on the connecting bridge of the tower; the groups of frightened guests on the terrace, and his mother standing unmoved amongst them in her sumptuous purple dress and the diamonds in her hair; the arrival of the fire-engine from Sedgwick; and then, just at the end, the figure of a man appearing on the bridge, with a cloak wound round his head, dashing into the doorway through which the smoke was issuing in great waves; his sudden flight across the bridge again; and then Jane, at his elbow, clasping his arm and saying, in a terrified tone, 'Oh, Peter! for a moment I thought it was you!' Dunbar was scribbling rapidly in his notebook. 'It is as clear as mud!' he said at last. 'Purvis, after the _Rosana_ incident, was missing for a considerable time, and it is believed that his English wife at Rosario hid him somewhere. There he probably heard the story of his adoption, and determined to prove himself the eldest son.' 'I don't understand how he could have heard the story,' said Peter. 'He heard most things. But there are links in the chain that we shall never get a sight of; we see only the beginning and the end of it,' replied Dunbar. The Scot was very seldom excited; but he got up from his chair and began to walk rapidly up and down the room, his under-lip stuck out, and his tough hair thrown back from his forehead. 'The whole thing depended upon his getting what direct information he could about the property, and he must have worked this thing well. The fire, I take it, was accidental?' 'Oh, the fire was accidental enough,' said Peter, 'and was found to be due to some electric lighting which was put into the tower.' 'Purvis's visit to England must have been to ascertain if Mrs. Ogilvie were still alive, and, in the first instance, he probably meant to levy blackmail upon her; he must have discovered where she kept her papers, and have tried to effect an entrance on the night of the ball when many strangers were about.' 'I believe,' exclaimed Peter, 'we saw him in one of the corridors of the house during the dance, and decided that he must be one of the guests unknown to us, who had come with some country neighbour, and that he had lost his way amongst the almost interminable passages of the place.' He saw himself and Jane making for the leather-covered door which led to the bridge, and the shrinking stranger, with his hopelessly timid manner, who had drawn back at their approach; and he thought he heard himself saying, 'Shall I get him some partners, or leave the people who brought him to the dance to look after him?' It was only a fleeting look that he had caught of the man's face, and he recalled it with difficulty now, but it was not a far-fetched conclusion to decide that the two were one and the same man.