Mark spoke in a resentful tone; he did not like the reflection that he thought was cast upon him by the question. Dr. Davenal said no more. He supposed Mark _was_ sure of his hand's skill. "I shall give her chloroform," resumed Mark. "No!" burst forth Dr. Davenal. He could not have interrupted more impetuously had he been interposing to dash it from her lips. He believed that Lady Oswald would be a very unfit subject for chloroform; one of those few to whom it is not safe to administer it; and he explained this to Mark Cray. Mark turned restive. Strange to say, he, who had hitherto been content to follow in the medical steps of Dr. Davenal, watching his treatment, pursuing the same, more as a pupil takes lessons of a master than as a man in practice for himself, seemed inclined to turn restive now. Did Mark Cray, because he had married the doctor's niece, had become connected with him by private ties, was now a more equal partner, fully recognised--did he deem it well to exercise that right of independence which we all love, for it is inherent in the hearts of the best of us, and to stand up for his own ways and his own will? "I like chloroform," he said. "I consider it one of the most blessed inventions of the age." "Undoubtedly; where it can be safely used." "I have used it fifty times," rejoined Mark. "I have used it fifty and fifty to that," said the doctor, good-humouredly. "But, Mark, I never used it in my life upon a doubtful subject, and I never will use it upon one." "What do you call a doubtful subject?" "What do I call a doubtful subject?" repeated the doctor. "You know as well as I. How many patients has chloroform killed? Upon certain natures"---- "Very few," interrupted Mark. "Very few, as compared to the whole," acquiesced the doctor. "You may administer chloroform with perfect safety to ninety-nine patients, and you cannot to the hundredth. Upon certain natures, as I was about to observe, its effects may be fatal. And where there is this doubt, Mark, it should be acted upon." "The cases are so rare." "True. And the important thing for a medical man, in these cases, is to discern where chloroform may be given with safety and where it may not." "It is impossible that he can do that with any certainty." "Not at all," said Dr. Davenal. "I never knew my judgment fail. I believe it is a gift, this ability to distinguish the subtle difference in natures. Perhaps I may call it instinct, more than judgment, for I think it could not deceive or lead me to an erroneous decision." "I am not sure that I understand you," said Mr. Cray. "My belief is, that I possess nothing of the sort. I think you must be talking of a species of second sight."