ts.
Suddenly he looked up.

"Has that lady left the place yet, Emil?"

"No, monsieur!"

Mr. Sabin smiled.

"Have you a back exit?" he asked.

"None that the lady would know of," Emil answered. "She must pass along
the passage which borders this apartment, and enter the bar by a door
from behind. If monsieur desires it, it is impossible for her to leave
unobserved."

"That is excellent, Emil," Mr. Sabin said. "Now there is one more
question--quite a harmless one. Annette spoke of my life being in some
way insured."

"It is true, monsieur," Emil admitted. "A lady who also possessed
the yellow crayon came here the day that--that monsieur incurred the
displeasure of--of his friends. She tried to bribe me to blow up my
laboratory and leave the country, or that I should substitute a harmless
powder for any required by the Prince. I was obliged to refuse."

"And then?"

"Then she promised me a large sum if you were alive in six months, and
made me at once a payment.

"Dear me," Mr. Sabin said, "this is quite extraordinary."

"I can tell monsieur the lady's name," Emil continued, "for she raised
her veil, and everywhere the illustrated papers have been full of her
picture. It was the lady who was besieged in a little town of South
Africa, and who carried despatches for the general, disguised as a man."

"Lady Carey!" Mr. Sabin remarked quietly.

"That was the lady's name," Emil agreed.

Mr. Sabin was thoughtful for a few moments. Then he looked up.

"Emil Sachs," he said sternly, "you have given out at least one portion
of your abominable concoction which is meant to end my days. Whether I
shall escape it or not remains to be seen. I am forced at the best to
discharge my servant, and to live the life of a hunted man. Now you have
done enough mischief in the world. To-morrow morning a messenger will
place in your hands two hundred pounds. A larger sum will await you at
Baring's Bank in New York. You will go there and buy a small restaurant
in the business quarter. This is your last chance, Emil. I give it to
you for the sake of Annette."

"And I accept it, monsieur, with gratitude."

"For the present--"

Mr. Sabin stopped short. His quick ears had caught the swish of woman's
gown passing along the passage outside. Emil too had heard it.

"It is the dark lady," he whispered, "who purchased from me the other
powder. See, I open gently this door. Monsieur must both see and hear."

The door at the end of t