“But you have made more important inventions than this, haven’t you?” he asked when the other stopped talking.  Varna’s eyes flashed and his voice dropped to a tone of mystery as he answered:  “Yes indeed I have.  But I did not have time to finish them.  For I had become some one else.”

“Some one else?”

“Cardillac,” whispered Varna, whose mania was now getting the best of him again.

“Cardillac?  You mean the notorious goldsmith who lived in Paris 200 years ago?  Why, he’s dead.”

Varna’s pale lips curled in a superior smile.  “Oh, yes—­that’s what people think, but it’s a mistake.  He is still alive—­I am —­I have—­although of course there isn’t much opportunity here—­”

Gyuri cleared his throat with a rasping noise.

“What were you saying, friend Cardillac?” asked Muller with a great show of interest.

“I have done things here that nobody has found out.  It gives me great pleasure to see the authorities so helpless over the riddles I have given them to solve.  Oh, indeed, sir, you would never imagine how stupid they are here.”

“In other words, friend Cardillac, you are too clever for the authorities here?

“Yes, that’s it,” said the insane man greatly flattered.  He raised his head proudly and smiled down at his guest.  At this moment the doctor came into the room and Gyuri walked forward to the group at the window.

“You are making him nervous, sir,” he said to Muller in a tone that was almost harsh.

“You can leave that to me,” answered the detective calmly.  “And you will please place yourself behind Mr. Varna’s chair, not behind mine.  It is your eyes that are making him uneasy.”

The attendant was alarmed and lost control of himself for a moment.  “Sir!” he exclaimed in an outburst.

“My name is Muller, in case you do not know it already, Joseph Muller, detective.  Gyuri Kovacz, you will do what I tell you to!  I am master here just now.  Is it not so, doctor?”

“Yes, it is so,” said the doctor.

“What does this mean?” murmured Gyuri, turning pale.

“It means that the best thing for you to do is to stand up against that wall and fold your arms on your breast,” said Muller firmly.  He took a revolver from his pocket and laid it beside him on the turning-lathe.  The young giant, cowed by the sight of the weapon, obeyed the commands of this little man whom he could have easily crushed with a single blow.

Dr. Orszay sank down on the chair beside the door.  Muller, now completely master of the situation, turned to the insane man who stood looking at him in a surprise which was mingled with admiration.

“And now, my dear Cardillac, you must tell us of your great deeds here,” said the detective in a friendly tone.

The unfortunate man bent over him with shining eyes and whispered:  “But you’ll shoot him first, won’t you?”