Then Hanaud lit another cigarette.
Mr. Ricardo, on the other hand, could hardly continue to smoke for excitement.
"I cannot understand your calmness," he exclaimed.
"No?" said Hanaud. "Yet it is so obvious. You are the amateur, I am the professional-that is all."
He looked at his watch and rose to his feet.
"I must go" he said and as he turned towards the door a cry sprang from Mr. Ricardo’s lips "It is true. I am the amateur. Yet I have knowledge, Monsieur Hanaud which the professional would do well to obtain."
Hanaud turned a guarded face towards Ricardo. There was no longer any raillery in his manner. He spoke slowly, coldly.
"Let me have it then!"
"I have driven in my motor-car from Geneva to Aix," Ricardo cried excitedly. "A bridge crosses a ravine high up amongst the mountains. At the bridge there is a Custom House. There-at the Pont de la Caille-your car is stopped. It is searched. You must sign your name in a book. And there is no way round. You would find sure and certain proof whether or no Madame Dauvray’s car travelled last night to Geneva. Not so many travellers pass along that road at night. You would find certain proof too of how many people were in the car. For they search carefully at the Pont de la Caille."
A dark flush overspread Hanaud’s face. Ricardo was in the seventh Heaven. He had at last contributed something to the history of this crime. He had repaired an omission. He had supplied knowledge to the omniscient. Wethermill looked up drearily like one who has lost heart.