No one but Dr. Heriot guessed how Mildred's strength was failing; but his well-meant inquiries were evidently so unpalatable that he forbore to press them. Only once or twice he hinted to Mr. Lambert that he thought his sister was looking less strong than usual, and wanted change of air. 'Heriot tells me that you are not looking well--that you want a change, Mildred,' her brother said to her one day, and, to his surprise, she looked annoyed, and answered more hastily than her wont-- 'There is nothing the matter with me, at least nothing of consequence. I am not one of those who are always fancying themselves ill.' 'But you are thinner. Yes, I am sure he is right; you are thinner, Mildred.' 'What nonsense, Arnold; he has put that in your head. By and by I shall be glad of a little change, I daresay. When Mr. Fabian leaves Roy, I mean to take his place.' 'A good idea,' responded Mr. Lambert, warmly; 'it will be a treat for Rex, and will do you good at the same time. I was thinking of running up myself after Christmas. One sees so little of the boy, and his letters are so short and unsatisfactory; he seems a little dull, I fancy.' 'Mr. Fabian will cheer him up,' replied Mildred, evasively. She was thankful when her brother went back to his study. She felt more than usually oppressed and languid that day, though she would not own it to herself; her work wearied her, and the least effort to talk jarred the edge of her nerves. 'How dreadful it is to feel so irritable and cross, as I have done lately,' she thought. 'Perhaps after all he is right, and I am not so strong as usual; but I cannot have them all fancying me ill. The bare idea is intolerable. If I am going to be ill, I hope I may know it, that I may get away somewhere, where his kindness will not kill me.' She shivered here, partly from the thought, and partly from the opening of the door. A keen wind whistled through the passage, a rush of cold air followed Polly as she entered. Dr. Heriot was with her. His cordial greeting was as hearty as ever. 'All alone, and in the dark, and positively doing nothing; how unlike Aunt Milly,' he said, in his cheerful quizzical voice; and kneeling down on the rug, he stirred the fire, and threw on another log, rousing a flame that lighted up the old china and played on the ebony chairs and cabinet. The shadows had all fled now, the firelight gleamed warmly on the couch, where Mildred was sitting in her blue dress, and on Dr. Heriot's dark face as he threw himself down in the easy-chair that, as he said, looked so inviting. 'Polly is tired, and so am I. We have been having an argument that lasted us all the way from Appleby.' And he leant back his head on the cushions, and looked up lazily at Polly as she stood beside him in her soft furs, swinging her hat in her hand and gazing into the fire. 'Polly, do be reasonable and sit down!' he exclaimed, coaxingly.