"Don't talk, old chap. Not serious, I hope, doctor?" said the Mephistophelean man. "Cab seemed to come out of the fog, and he was knocked down. I got an ugly blow on the shoulder."

"Get me some brandy," said the injured man faintly. "My chest's crushed."

"No, no, not so bad as that," said the doctor kindly. "You shall have a stimulus soon. Now, then, suppose we see what the damage is. A broken rib, I expect, and that will only mean a little pain. Now, then."

His busy fingers were rapidly and tenderly unbuttoning the injured man's coat, while a gasping moan came from his lips.

"Hurts me horribly--to breathe, doctor."

There was a gasping sound, and the Mephistophelean man reeled, tried to save himself, and fell against the consulting-room door, which somehow flew open, revealing the sleeping figure of Mark Heath on the couch.

"My dear sir--faint?"

"I beg your pardon, doctor," said the sinister-looking man. "Sick as a great girl. I can bear pain, but to see him like that turned me over.

No, no, see to him; I'm better now."

The doctor continued his task, while the door swung to once more.

"Still feel faint?" said the doctor, without looking up.

"Oh, no; it's all gone now. I really am ashamed."

"Nothing to be ashamed of, my dear sir. It is a man's nature. Now I shall be obliged to ask one of you to lend me a little assistance here."

The bearded man stood ready, and exchanged a glance with his Mephistophelean companion, who was behind the doctor now.

"Ah!"

Dr Chartley uttered a quick ejaculation, for, as he bent over his patient, the man behind struck him a heavy blow with a short thick life-preserver, and, quick almost as lightning, delivered another crashing stroke on the back of the head.

Without so much as a groan, merely a catching at the air, the doctor fell forward upon his supposed patient, and then rolled with a dull heavy sound upon the carpet, to lie motionless--to all appearance dead.

"Yah! what a butcher you are, Rogers!" said the sham patient, in a querulous high-pitched tone.

"Hold your row! Quick! Listen at that door."

The sham patient sprang to the door at the end of the passage, opened it softly, and stood listening.

"All right," he whispered, "still as death."

"Curse you! hold your row about death," whispered the other as the door was closed. "Lock it."

"I was going to," said the younger man, turning the key softly. "Is he there, Harry?"

"Yes; all right," came in a whisper from the bearded man, who had softly opened the consulting-room door and peered in at the sleeping figure upon the couch. "Quick! come on."

The man addressed as Rogers had stooped down and then gone on one knee, thrusting the life-preserver into his pocket while he examined the doctor, and not noticing that it slipped out onto the skirt of his coat, and rolled aside as he finished his examination, and satisfied himself that there was nothing to be apprehended there.

He started up, and followed his companion on tiptoe, and the next minute they were gazing down at the man they had tracked from the diamond-fields and run to earth at last.

"Hah!" exclaimed the Mephistopheles of the party; "that's right. Give him one if he moves."

This to his bearded companion, who had drawn a life-preserver similar to that his companion had used, as he bent over the sleeping man.

"He has had a dose," was whispered back. "You can smell his breath."

"Brandy. All right!" cried the youngest of the three, catching up the decanter, smelling it, tasting it with a loud smack of the lips, and pouring out a goodly portion in the empty glass, he handed it to his first companion. "Here, Harry."

"Sure it's all right?" was whispered back.

"Swear it. Now, Rogers."

"Here's mine," said the man, with a grin. "Hot with. Quick, lads!"

"Don't touch that," was on the younger man's lips; but his companion raised the glass with a laugh, and as he followed his example by putting the decanter to his mouth, the doctor's assailant literally poured the contents of the tumbler down his throat, and then stood still, put the glass back on the table, gasping and staring straight before him.

His companions were not heeding him, for each drank eagerly of the brandy, and were setting down the decanter and glass, when the younger man spoke:

"Why, Rogers, old chap!"

The man addressed turned his wild staring eyes at him for a moment, as if to answer, and then walked blindly between the sofa and the table, as if to go straight to the wall, reeled and fell, catching at the cloth, which he dragged aside, nearly causing the lamp to go crashing on the floor.

For a few moments the others stood aghast, staring at their prostrate companion, who writhed slightly for a brief period, uttering a curious sound, and then lay upon his back, stretched out motionless.

The younger man was the first to recover himself.

"Help!" he gasped, in a hoarse whisper.

"Hush!" cried his companion; "are you mad?"

He raised his life-preserver threateningly, and the other gazed at him with ghastly face and staring eyes.

"What shall we do?" he whispered.

"Keep your head, and don't be a fool," was the reply.

As the bearded man spoke he went down on one knee, thrust his hand into his comrade's breast, and then rose quickly.

"What is it, Harry--poison?"

"Yes, grim death, lad."

"Then, we've got it, too."

"No--all right. The fool! Smell that glass."

He took up and held the tumbler to his nose, and then passed it to his companion, who smelt it, and put it down with a shudder.

"Come on," he panted; "let's get away."