“That the little game of ‘Bluff’ has worked, Dr. Finch, and you’ll never draw a revolver on me,” rapped in Cleek, giving him a backward push that carried him to the floor, and in the twinkling of an eye he had pounced upon him like a cat and was saying, as he snapped the handcuffs upon his wrists:  “Got you, you brute-beast; got you tight and fast!  Do you remember Hamilton, the medical student, in New Zealand, eight years ago?  Do you?  Well, that’s the man you’re dealing with now!”

The man, struggling and kicking, biting and clawing like any other cornered wild cat, flung out a cry of utter despair at this, and collapsed suddenly; and in the winking of an eye Cleek’s hands had flashed into the two pockets of the dressing-gown the fellow was wearing, and flashed out again with a revolver in one and a shining nickel thing in the other.

“Got your ‘bark,’ doctor, and got your ‘bite’ as well!” he said, as he rose to his feet.  “You’d have put a bullet through me at the first word, wouldn’t you, but for that little ‘bluff’ of suspecting and arresting another man?  Captain, look to Miss Comstock—­I think she has fainted.  You wanted the murderer of Mrs. Comstock and her children, didn’t you?  Well, here he is, the rascal!”

“Good God!  Then it—­it’s not a mistake?  You mean it—­mean it?  And Uncle Phil!  You accuse Uncle Phil?”

“Uncle Nothing!” flung back Cleek with a sort of laugh—­and, hazarding a guess which afterwards was proved to be the truth—­“I’ll lay my life, Captain, that when you apply to the Australian authorities you will find that old Mr. Philip Harmstead is in his grave; that he was attended in his last illness by one Dr. Frederick Finch, to whom his fortune would revert in the event of Mrs. Comstock and her children dying.  Finch is the fellow’s name—­isn’t it, doctor, eh?”

“Finch?” repeated the Captain.  “Good Heaven!  Why that was the name of the woman who was old Mr. Harmstead’s housekeeper—­you know, the widow I told you about to-night.”

“Oho!” said Cleek.  “That’s possibly where the threads join and this little game begins.  Or perhaps it may really be said to begin again where Shorty, the chemist, died, and the celebrated Spofford mystery ended—­eh, doctor?  Look here, Captain, look here, Mr. Narkom, you remember what I told you this morning about that case in New Zealand which so strongly resembled this one?  That was the Spofford mystery.  Do you remember what I said about hitting upon a theory and offering it to the medical fraternity, only to get laughed at for my pains?  Well, it was to this man, Dr. Frederick Finch, I advanced that theory, and it was Dr. Frederick Finch who jeered at it, but has now made deadly use of it, the hound.  Do you want to know how he killed his victims, and what he used?  Look at this thing that you saw me take from the pocket of his dressing-gown.  It is a hypodermic syringe, but there is nothing in it—­there never has been anything in it.  Air was his poison—­air