“What has become of him? In all probability, his confederates removed his corpse at the same time that they carried away the girl; but what proof have we? None at all. Any more than of his staying in the ruins, or of his death, or of his life. And that is the real mystery, M. Beautrelet. The murder of Mlle. Raymonde solves nothing. On the contrary, it only complicates matters. What has been happening during the past two months at the Château d’Ambrumésy? If we don’t clear up the riddle, young man, others will give us the go-by.” “On what day are those others coming?” “Wednesday—Tuesday perhaps—” Beautrelet seemed to be making an inward calculation and then declared: “Monsieur le Juge d’Instruction, this is Saturday. I have to be back at school on Monday evening. Well, if you will have the goodness to be here at ten o’clock exactly on Monday morning, I will try to give you the key to the riddle.” “Really, M. Beautrelet—do you think so? Are you sure?” “I hope so, at any rate.” “And where are you going now?” “I am going to see if the facts consent to fit in with the general theory which I am beginning to perceive.” “And if they don’t fit in?” “Well, Monsieur le Juge d’Instruction,” said Beautrelet, with a laugh, “then it will be their fault and I must look for others which, will prove more tractable. Till Monday, then?” “Till Monday.” A few minutes later, M. Filleul was driving toward Dieppe, while Isidore mounted a bicycle which he had borrowed from the Comte de Gesvres and rode off along the road to Yerville and Caudebec-en-Caux. There was one point in particular on which the young man was anxious to form a clear opinion, because this just appeared to him to be the enemy’s weakest point. Objects of the size of the four Rubens pictures cannot be juggled away. They were bound to be somewhere. Granting that it was impossible to find them for the moment, might one not discover the road by which they had disappeared? What Beautrelet surmised was that the four pictures had undoubtedly been carried off in the motor car, but that, before reaching Caudebec, they were transferred to another car, which had crossed the Seine either above Caudebec or below it. Now the first horse-boat down the stream was at Quillebeuf, a greatly frequented ferry and, consequently, dangerous. Up stream, there was the ferry-boat at La Mailleraie, a large, but lonely market-town, lying well off the main road. By midnight, Isidore had covered the thirty-five or forty miles to La Mailleraie and was knocking at the door of an inn by the waterside. He slept there and, in the morning, questioned the ferrymen. They consulted the counterfoils in the traffic-book. No motor-car had crossed on Thursday the 23rd of April. “A horse-drawn vehicle, then?” suggested Beautrelet. “A cart? A van?” “No, not either.”