Duvall laughed. "We are dealing with a far shrewder man than that, Vernet. This fellow will do no telephoning."
"Then how will he let Monsieur Stapleton know?"
"That is just what I am trying to find out. Put yourself in his place. He is known—he dare not remain in Paris—he gets five hundred thousand francs to give up the child. Is it not natural to suppose that he will leave the city at once?"
"Yes. That is what I should do, in his place."
"Of course. Now I understand that the fellow will walk from Mr. Stapleton's house to the Arc de Triomphe, a distance of six hundred yards. He can do that easily in ten minutes."
"Yes."
"Once at the arch, he will stand awaiting a fast automobile, which will come along the Champs Élysées. This automobile will stop for an instant and pick him up, then proceed at high speed along the Avenue du Bois de Boulogne."
"Because it will afford him the quickest and safest road out of Paris. From the arch to the Porte Dauphine is less than a mile. He can make it in five minutes. In fifteen minutes altogether then, he is outside the walls. In another fifteen minutes, he is beyond pursuit, in the country."
"But you forget, Monsieur Duvall, that he has not yet advised his confederates that all is well, and that the address of the place where the boy is hidden is to be telephoned to Mr. Stapleton."