belin!"

"The brute!" muttered Pougeot.

Then they turned to the commissary's report of his investigation, Coquenil
listening with intense concentration, interrupting now and then with a
question or to consult the rough plan drawn by Pougeot.

"Are you sure there is no exit from the banquet room and from these private
rooms except by the corridor?" he asked.

"They tell me not."

"So, if the murderer went out, he must have passed Joseph?"

"Yes."

"And the only persons who passed Joseph were the woman and this American?"

"Exactly."

"Too easy!" he muttered. "Too easy!"

"What do you mean?"

"That would put the guilt on one or the other of those two?"

"Apparently."

"And end the case?"

"Why--er----"

"Yes, it would. A case is ended when the murderer is discovered. Well, this
case is _not_ ended, you can be sure of that. The murderer I am looking for
_is not that kind of a murderer_. To begin with, he's not a fool. If he
made up his mind to shoot a man in a private room he would know _exactly_
what he was doing and _exactly_ how he was going to escape."

"But the facts are there--I've given them to you," retorted the commissary
a little nettled.

Coquenil shook his head.

"My dear Lucien, you have given me _some_ of the facts; before morning I
hope we'll have others and--hello!"

He stopped abruptly to look at a comical little man with a very large
mouth, the owner of the place, who had been hovering about for some moments
as if anxious to say something.

"What is it, my friend?" asked Coquenil good-naturedly.

At this the proprietor coughed in embarrassment and motioned to a prim,
thin-faced woman in the front room who came forward with fidgety shyness,
begging the gentlemen to forgive her if she had done wrong, but there was
something on her conscience and she couldn't sleep without telling it.

"Well?" broke in Pougeot impatiently, but Coquenil gave the woman a
reassuring look and she went on to explain that she was a spinster living
in a little attic room of the next house, overlooking the Rue Marboeuf. She
worked as a seamstress all day in a hot, crowded _atelier_, and when she
came home at night she loved to go out on her balcony, especially these
fine summer evenings. She would stand there and brush her hair while she
watched the sunset deepen and the swallows circle over the chimney tops. It
was an excellent thing for a woman's hair to brush it a long time every
night; she always br