Rick could not understand it, so, finding that poking his nose into the hand that hung down over the arm of the chair, and giving vent to small whines, produced no effect, he suddenly jumped on to his master’s knee and commenced to lick vigorously the hand upon which Magnus had rested his forehead. With a start and a laugh Magnus came back to earth, for, if the truth must be told, he had been indulging in a habit which had become common with him of late, viz., building castles in the air. In these, too, a very large part was played by a certain golden-haired, hazel-eyed young lady known to the reader under the name of Marielle Heritage. For it had come to this, that Magnus Duncan’s true heart had found its liege lady, and his life’s happiness depended upon the answer that Marielle would give to a certain question which he intended to put to her before long. “If I could only be sure of her!” sighed Magnus to himself. “But she is so modest and shy, she will never let me be certain she cares for me. I think she does though, in spite of the reserve she wraps herself up in. My queen!” Humming unconsciously the air of Blumenthal’s exquisite song, young Dr. Duncan got up and fetched his hat and stick. Rick took this as an invitation to a walk, and immediately began to utter a series of sharp shrill barks expressive of his delight at the prospect. But he was doomed to disappointment after all, for just as Magnus was leaving the house a messenger came up in hot haste bearing a note. Opening it the young man read, “Please come at once to 27, York Road. My mother is seriously ill, and I do not know what is the matter with her.—M. H.” Magnus only waited to secure his bag, into which he put various things of use in emergencies, then hailing a hansom he was driven rapidly along to York Road. Arrived there he was shown up at once into the room where Mrs. Heritage was lying in bed, with Marielle standing anxiously beside her. One glance from the keen blue eyes at the face upon the pillow told Magnus Duncan what was amiss. Marielle only whispered, “I am so glad you have come,” then turning to Mrs. Heritage said, “Mother darling, here is the doctor come to see you.” An inarticulate effort at speech accompanied by a bewildered look was the only response, and Marielle turned the most piteous of faces to meet the kindly eyes of the young man, saying, “She has been like this for nearly two hours now, and I cannot think what causes it.” Magnus Duncan beckoned the girl to come a little further away from the invalid while he made a careful examination of the helpless limbs. He could not trust himself to speak at the moment. Her trouble almost unmanned him. The examination over, the young doctor asked that one of the servants might be told to remain in the sick-room while he had a little talk with Marielle downstairs, and as soon as they reached the little drawing-room he asked, “Tell me just how this began?”