Dr. Cumberly glared at his fellow practitioner, angrily. “Are there no other marks of injection?” he asked. “On the left forearm, yes. Obviously self-administered. Oh, I don't deny the habit! But my point is this: the injection in the shoulder was NOT self-administered.” “Come, Helen,” said Cumberly, taking his daughter's arm; for she had drawn near, during the colloquy--“you must get to bed.” His face was very stern when he turned again to Mr. Hilton. “I shall return in a few minutes,” he said, and escorted his daughter from the room. VI AT SCOTLAND YARD Matters of vital importance to some people whom already we have met, and to others whom thus far we have not met, were transacted in a lofty and rather bleak looking room at Scotland Yard between the hours of nine and ten A. M.; that is, later in the morning of the fateful day whose advent we have heard acclaimed from the Tower of Westminster. The room, which was lighted by a large French window opening upon a balcony, commanded an excellent view of the Thames Embankment. The floor was polished to a degree of brightness, almost painful. The distempered walls, save for a severe and solitary etching of a former Commissioner, were nude in all their unloveliness. A heavy deal table (upon which rested a blotting-pad, a pewter ink-pot, several newspapers and two pens) together with three deal chairs, built rather as monuments of durability than as examples of art, constituted the only furniture, if we except an electric lamp with a green glass shade, above the table. This was the room of Detective-Inspector Dunbar; and Detective-Inspector Dunbar, at the hour of our entrance, will be found seated in the chair, placed behind the table, his elbows resting upon the blotting-pad. At ten minutes past nine, exactly, the door opened, and a thick-set, florid man, buttoned up in a fawn colored raincoat and wearing a bowler hat of obsolete build, entered. He possessed a black mustache, a breezy, bustling manner, and humorous blue eyes; furthermore, when he took off his hat, he revealed the possession of a head of very bristly, upstanding, black hair. This was Detective-Sergeant Sowerby, and the same who was engaged in examining a newspaper in the study of Henry Leroux when Dr. Cumberly and his daughter had paid their second visit to that scene of an unhappy soul's dismissal. “Well?” said Dunbar, glancing up at his subordinate, inquiringly. “I have done all the cab depots,” reported Sergeant Sowerby, “and a good many of the private owners; but so far the man seen by Mr. Exel has not turned up.” “The word will be passed round now, though,” said Dunbar, “and we shall probably have him here during the day.” “I hope so,” said the other good-humoredly, seating himself upon one of the two chairs ranged beside the wall. “If he doesn't show up.”... “Well?” jerked Dunbar--“if he doesn't?” “It will look very black against Leroux.”