the one leading
into a large closet in the opposite wall.

Nick opened the latter, and found the closet hung with Cervera's
extensive wardrobe. He thrust his arm along the garments hanging at
either side, and sounded the three walls, and then the closet floor, all
of which appeared perfectly firm and solid.

Even these precautions seemed quite needless to Nick, however, it being
a rented house, and Cervera presumably uninformed of his coming.

"Now, senora, you may have just ten minutes to make ready," said he, as
he rejoined her. "I shall leave this chamber door open, and will wait
for you in the adjoining hall. Can you whistle?"

"Whistle?"

"Yes, whistle! You know what it is to whistle, don't you?"

The sneer on Cervera's red lips, as she arose from her chair, became
almost a smile.

"Yes, I can whistle after a fashion," she admitted.

"Well, then, you keep whistling all the time you are alone here," Nick
sternly commanded. "I will let you out of my sight to make these
changes, but not out of my hearing."

"Suspicious fool!"

"Fool or not, you keep whistling," said Nick, bluntly. "If you let up
for so long as a second, I'll come over yonder threshold in a way that
you'll not fancy."

"But suppose I want to brush my teeth?" inquired Cervera, with a
vixenish light in her evil eyes. "I cannot whistle and brush my teeth,
Detective Carter."

"You'll have plenty of time to brush your teeth at the Tombs," said
Nick, sharply. "Now look lively, mark you, and--keep whistling."

Cervera at once began to whistle.

Nick removed the key from the chamber door, and sauntered out into the
hall, where he kept his ears constantly alert.

Not for a moment did the whistling cease, nor was there the slightest
change in tone or character.

Nick could not have taken a more effective method to serve his present
purpose.

At the end of eight minutes the whistling ceased, and Cervera coldly
cried:

"Now you may come in, Detective Carter. I am about ready to go with
you."

Mick at once entered the chamber.

Cervera had changed her evening dress for a complete suit of black, and
was standing in the middle of the room.

"I suppose," said she, staring icily at the detective, "that I ought to
thank you for your consideration."

"Don't trouble yourself," said Nick, curtly. "I have no time to waste."

"Yet just one word, Detective Carter, before we go."

"Let it be brief, then."

"You are said to be a very clever m