had prepared an excellent dinner, and nobody paid any attention
to it.

M. Lecoq was fond of tit-bits; yet, when Louis placed on the table
a dish of superb grapes--quite out of season--his mouth did not
so much as expand into a smile. Dr. Gendron would have been
puzzled to say what he had eaten. The dinner was nearly over, when
M. Plantat began to be annoyed by the constraint which the presence
of the servants put upon the party. He called to the cook:

"You will give us our coffee in the library, and may then retire,
as well as Louis."

"But these gentlemen do not know their rooms," insisted Mme. Petit,
whose eavesdropping projects were checked by this order. "They will,
perhaps, need something."

"I will show them their rooms," said M. Plantat, dryly. "And if
they need anything, I shall be here."

They went into the library. M. Plantat brought out a box of cigars
and passed them round:

"It will be healthful to smoke a little before retiring."

M. Lecoq lit an aromatic weed, and remarked:

"You two may go to bed if you like; I am condemned, I see, to a
sleepless night. But before I go to writing, I wish to ask you a
few things, Monsieur Plantat."

M. Plantat bowed in token of assent.

"We must resume our conversation," continued the detective, "and
compare our inferences. All our lights are not too much to throw
a little daylight upon this affair, which is one of the darkest I
have ever met with. The situation is dangerous, and time presses.
On our acuteness depends the fate of several innocent persons, upon
whom rest very serious charges. We have a theory: but Monsieur
Domini also has one, and his, let us confess, is based upon material
facts, while ours rests upon very disputable sensations and logic."

"We have more than sensations," responded M. Plantat.

"I agree with you," said the doctor, "but we must prove it."

"And I will prove it, parbleu," cried M. Lecoq, eagerly. "The
affair is complicated and difficult--so much the better. Eh!
If it were simple, I would go back to Paris instanter, and to-morrow
I would send you one of my men. I leave easy riddles to infants.
What I want is the inexplicable enigmas, so as to unravel it; a
struggle, to show my strength; obstacles, to conquer them."

M. Plantat and the doctor looked steadily at the speaker. He was
as if transfigured. It was the same yellow-haired and whiskered
man, in a long overcoat: yet the voice, the physiognomy, the very
features, ha