were sitting over their coffee. Hanaud
lighted a cigar.

"There were difficulties, of course," he said; "the crime was so
carefully planned. The little details, such as the footprints, the
absence of any mud from the girl's shoes in the carriage of the
motor-car, the dinner at Annecy, the purchase of the cord, the want of
any sign of a struggle in the little salon, were all carefully thought
out. Had not one little accident happened, and one little mistake been
made in consequence, I doubt if we should have laid our hands upon one
of the gang. We might have suspected Wethermill; we should hardly have
secured him, and we should very likely never have known of the Tace
family. That mistake was, as you no doubt are fully aware--"

"The failure of Wethermill to discover Mme. Dauvray's jewels," said
Ricardo at once.

"No, my friend," answered Hanaud. "That made them keep Mlle. Celie
alive. It enabled us to save her when we had discovered the whereabouts
of the gang. It did not help us very much to lay our hands upon them.
No; the little accident which happened was the entrance of our friend
Perrichet into the garden while the murderers were still in the room.
Imagine that scene, M. Ricardo. The rage of the murderers at their
inability to discover the plunder for which they had risked their
necks, the old woman crumpled up on the floor against the wall, the
girl writing laboriously with fettered arms 'I do not know' under
threats of torture, and then in the stillness of the night the clear,
tiny click of the gate and the measured, relentless footsteps. No
wonder they were terrified in that dark room. What would be their one
thought? Why, to get away--to come back perhaps later, when Mlle. Celie
should have told them what, by the way, she did not know, but in any
case to get away now. So they made their little mistake, and in their
hurry they left the light burning in the room of Helene Vauquier, and
the murder was discovered seven hours too soon for them."

"Seven hours!" said Mr. Ricardo.

"Yes. The household did not rise early. It was not until seven that the
charwoman came. It was she who was meant to discover the crime. By that
time the motor-car would have been back three hours ago in its garage.
Servettaz, the chauffeur, would have returned from Chambery some time
in the morning, he would have cleaned the car, he would have noticed
that there was very little petrol in the tank, as there had been when
he had left