"Yes," he said later, "it was a very painful sight, and I don't wonder you were alarmed. We may hope that good food will build him up a little, but I am afraid he will never be really cured;" and he affected the dismal and conventional air with which one speaks of hopeless illness, and yet beneath it I detected the delight that leapt up rampant within him, and fought and struggled to find utterance. It was as if one glanced down on the even surface of the sea, clear and immobile, and saw beneath raging depths, and a storm of contending billows. It was indeed to me a torturing and offensive problem that this man, who had so bounteously rescued me from the sharpness of death, and showed himself in all the relations of life full of benevolence and pity and kindly forethought, should so manifestly be for once on the side of the demons, and take a ghastly pleasure in the torments of an afflicted fellow-creature. Apart, I struggled with the horned difficulty, and strove to find the solution, but without the hint of a clue; beset by mystery and contradiction, I saw nothing that might help me, and began to wonder whether, after all, I had not escaped from the white mist of the suburb at too dear a rate. I hinted something of my thought to the professor; I said enough to let him know that I was in the most acute perplexity, but the moment after regretted what I had done, when I saw his face contort with a spasm of pain. "My dear Miss Lally," he said, "you surely do not wish to leave us? No, no, you would not do it. You do not know how I rely on you; how confidently I go forward, assured that you are here to watch over my children. You, Miss Lally, are my rear-guard; for, let me tell you, that the business in which I am engaged is not wholly devoid of peril. You have not forgotten what I said the first morning here; my lips are shut by an old and firm resolve, till they can open to utter no ingenious hypothesis or vague surmise but irrefragable fact, as certain as a demonstration in mathematics. Think over it, Miss Lally, not for a moment would I endeavor to keep you here against your own instincts, and yet I tell you frankly that I am persuaded that it is here, here amidst the woods, that your duty lies."