"Don't say that, doctor," said Mark, taking his hand. "You have forgotten. Don't you remember? That dreadful foggy night. I came to you, and you let me into the surgery?" "Yes, dear, you recollect," cried Rich, piteously. "I was utterly exhausted, and worn out--very much excited," continued Mark. "You took me into the consulting-room, and I lay down upon the sofa. You gave me brandy, and some narcotic." "Brandy and a narcotic," said the doctor, smiling; "rather a strange mixture. Did I?" "Yes; you recollect now?" said Mark eagerly. The doctor looked at him intently, and then at Rich; but ended by shaking his head slowly. "No," he said, "I do not recollect." "All this is maddening!" muttered Mark, "just when one's hopes were reviving, and there was a chance of discovering something. Doctor," he continued excitedly, "try and recollect." "Yes, dear, for Mark Heath's sake try," continued Rich; and Poynter ground his teeth, as he felt what he would give to evoke the same interest for himself. "I will try, my love," said the doctor blandly. "Of course." "Then you remember I told you I had just come from the Cape; that I had a bag of diamonds in my breast?" Poynter uttered a sneering laugh, which made Heath wince, and turn upon him wrathfully. "Diamonds? did you say a bag of diamonds?" said the doctor. "Yes, yes; you remember." "Was it not a very unsafe place to carry diamonds?" "Yes, of course it was; but I could trust no one but myself! You remember then, doctor?" Dr Chartley paused for a few moments, and shook his head again. "No," he said blandly, "I do not remember. Diamonds, you say?" "Yes, yes, diamonds!" "I hope they were not lost," said the doctor simply. "Yes; lost, lost!" cried Mark frantically. "The night you were struck down!" "Here, hold hard!" cried Poynter sharply. "Look here, Mr Mark Heath, you came here that night?" "Why do you interfere, sir?" "Never mind. P'r'aps I know something." "You know something?" "P'r'aps so. You say you came here--late?" "Yes, very late." "That night the doctor was struck down?" "Yes; but why do you ask?" "Because, you scoundrel, we've got the clue at last. You were the man!" So sudden was the charge that Mark literally staggered back, and, weak from his illness, he gasped, and looked to a superficial observer as much like a guilty man as ever recoiled from a sudden denunciation. But as a wave of the advancing tide merely retires to gain fresh force, Mark Heath recovered himself. "You scoundrel!" he cried; and he would have sprung at Poynter's throat, but for the restraining arm of Janet and Hendon. "Scoundrel yourself!" cried Poynter savagely. "Look at his face! Here--the police!" He strode towards the door, upon which at that moment there was a loud tapping; and before he could reach it, Bob stood in the opening, very rough of head, very ragged, and looking as if he had not been washed since he was missed. CHAPTER SIXTEEN. BOB IS EXPLANATORY.