Hardly a session passed at the Old Bailey but Sir Houston Bird appeared in the witness box, spruce in his morning-coat, and presenting somewhat the appearance of a bank-clerk; yet, in his cold unemotional words, he explained to the jury the truth as written plainly by scientific investigation. Many murderers had been hanged upon his words, always given with that strange, deliberate hesitation, and yet words--that could never, for a moment, be shaken by counsel for the defence. Indeed, long ago defending counsel had given up cross-examination on any evidence presented by Sir Houston Bird, who had at his service the most expert chemists and analysts which our time could produce. "This is a mystery," exclaimed the great expert, gazing upon the body of his friend with his big grey eyes. "Do you tell me that he was actually locked in here?" "Yes, Sir Houston," replied Thomasson. "Curious--most curious," exclaimed the great pathologist, as though speaking to himself. Then, addressing Sainsbury, after the latter had been speaking, he said: "The poor fellow declared that he'd been shot. Is that so?" "Yes. He said that he felt a sudden and very sharp pain, and the words he used were, `I've been shot! I know I have!'" "And yet there appears no trace of any wound, or injury," Sir Houston remarked, much puzzled. "Both windows and door were secured from the inside, therefore no assassin could possibly escape, sir," declared Thomasson. "I suppose there's no one concealed here in the room?" he added, glancing apprehensively around. In a few moments the three men had examined every nook and corner of the apartment--the two long cupboards, beneath the table, behind the heavy plush curtains and the chenille portiere. But nobody was in concealment. The whole affair was a profound mystery. Sir Houston, dark-eyed and thoughtful, gazed down upon the body of his friend. Sainsbury and Thomasson had already removed Jerrold's coat, and were searching for any bullet-wound. But there was none. Again Sir Houston inquired what the dying man had actually said, and again Sainsbury repeated the disjointed words which the prostrate man had gasped with his dying breath. To the pathologist it was quite clear first that Jerome Jerrold believed he had been shot; secondly that no second person could have entered the room, and thirdly that the theory of assassination might be at once dismissed. "I think that poor Jerrold has died a natural death--sudden and painful, for if he had been shot some wound would most certainly show," Sir Houston remarked. "There will have to be an inquest, won't there?" asked Sainsbury. "Of course. And, Thomasson, you had better ring up the police at once and inform them of the facts," urged Sir Houston, who, turning again to Sainsbury, added: "At the post-mortem we shall, of course, quickly establish the cause of death." Again he bent, and with his forefinger drew down the dead man's nether lip.