said harshly. "If
you wish to search my safe you must get a warrant."

T. X. shrugged his shoulders, and carefully unscrewing the instrument he
had employed and replacing it in the case, he returned it to his inside
pocket.

"It was at your invitation, my dear Monsieur Kara," he said suavely. "Of
course I knew that you were putting a bluff up on me with the key and
that you had no more intention of letting me see the inside of your safe
than you had of telling me exactly what happened to John Lexman."

The shot went home.

The face which was thrust into the Commissioner's was ridged and veined
with passion. The lips were turned back to show the big white even
teeth, the eyes were narrowed to slits, the jaw thrust out, and almost
every semblance of humanity had vanished from his face.

"You--you--" he hissed, and his clawing hands moved suspiciously
backward.

"Put up your hands," said T. X. sharply, "and be damned quick about it!"

In a flash the hands went up, for the revolver which T. X. held was
pressed uncomfortably against the third button of the Greek's waistcoat.

"That's not the first time you've been asked to put up your hands, I
think," said T. X. pleasantly.

His own left hand slipped round to Kara's hip pocket. He found something
in the shape of a cylinder and drew it out from the pocket. To his
surprise it was not a revolver, not even a knife; it looked like a small
electric torch, though instead of a bulb and a bull's-eye glass, there
was a pepper-box perforation at one end.

He handled it carefully and was about to press the small nickel knob
when a strangled cry of horror broke from Kara.

"For God's sake be careful!" he gasped. "You're pointing it at me! Do
not press that lever, I beg!"

"Will it explode!" asked T. X. curiously.

"No, no!"

T. X. pointed the thing downward to the carpet and pressed the knob
cautiously. As he did so there was a sharp hiss and the floor was
stained with the liquid which the instrument contained. Just one gush
of fluid and no more. T. X. looked down. The bright carpet had already
changed colour, and was smoking. The room was filled with a pungent and
disagreeable scent. T. X. looked from the floor to the white-faced man.

"Vitriol, I believe," he said, shaking his head admiringly. "What a dear
little fellow you are!"

The man, big as he was, was on the point of collapse and mumbled
something about self-defence, and listened without a word, whilst T.
X.