lp me now."

These words had an immediate effect upon the man, who touched his cap and
asked what he was to do.

"Go to this house," pointed M. Paul, "ring the bell and ask if there is a
note for M. Robert. If there is, bring the note to me; if there isn't,
never mind. If anyone asks who sent you, say M. Robert himself.
Understand?"

"_Oui, m'sieur_," replied the chauffeur, and, saluting again, he strode
away toward the house.

The detective watched his receding figure as it disappeared in the shadows,
then he called out: "Wait, I forgot something."

The chauffeur turned obediently and came back.

"Take a good look at him now," said Coquenil to Tignol in a low tone. Then
to the man: "There's a bad piece of ground in the yard; you'd better have
this," and, without warning, he flashed his electric lantern full in the
chauffeur's face.

"_Merci, m'sieur,_" said the latter stolidly after a slight start, and
again he moved away, while Tignol clutched M. Paul's arm in excitement.

"You saw him?" whispered the detective.

"Did I see him!" exulted the other. "Oh, the cheek of that fellow!"

"You recognized him?"

"Did I? I'd know those little pig eyes anywhere. And that brush of a
mustache! Only half of it was blacked."

"Good; that's all I want," and, stepping out of the auto, Coquenil changed
quickly to the front seat. Then he drew the starting lever and the machine
began to move.

"Halloa! What are you doing?" cried the chauffeur, running toward them.

"Going back to Paris!" laughed Coquenil. "Hope you find the walking good,
Gibelin!"

"It's only fifteen miles," taunted Tignol.

"You loafer, you blackguard, you dirty dog!" yelled Gibelin, dancing in a
rage.

"Try to be more original in your detective work," called M. Paul. "_Au
revoir_."

They shot away rapidly, while the outraged and discomfited fat man stood in
the middle of the road hurling after them torrents of blasphemous abuse
that soon grew faint and died away.

"What in the world does this mean?" asked Pougeot in astonishment.

Coquenil slowed down the machine and turned. "I can't talk now; I've got to
drive this thing. It's lucky I know how."

"But--just a moment. That note for M. Robert? There was _no_ Robert?"

"Of course not."

"And--and you knew it was Gibelin all the time?"

"Yes. Be patient, Lucien, until we get back and I'll tell you everything."

The run to Paris took nearly an hour, for they made a detour, and Coquenil
drov