The officer went up to his bedroom on the top floor and saw the parcel, done up in paper and string, on the table. He opened it and discovered a box. The box contained a key, a large, rusty key, of a shape and manufacture that were obviously old. What could it all mean? There was no address on the box and no mark. He presumed that there was some mistake which would come to light of itself; and he slipped the key into his pocket. "Enough riddles for one day," he thought. "Let's go to bed." But when he went to the window to draw the curtains he saw, across the trees of the Bois, a cascade of sparks which spread to some distance in the dense blackness of the night. And he remembered the conversation which he had overheard in the restaurant and the rain of sparks mentioned by the men who were plotting to kidnap Little Mother Coralie. . . . CHAPTER III THE RUSTY KEY When Patrice Belval was eight years old he was sent from Paris, where he had lived till then, to a French boarding-school in London. Here he remained for ten years. At first he used to hear from his father weekly. Then, one day, the head-master told him that he was an orphan, that provision had been made for the cost of his education and that, on his majority, he would receive through an English solicitor his paternal inheritance, amounting to some eight thousand pounds. Two hundred thousand francs could never be enough for a young man who soon proved himself to possess expensive tastes and who, when sent to Algeria to perform his military service, found means to run up twenty thousand francs of debts before coming into his money. He therefore started by squandering his patrimony and, having done so, settled down to work. Endowed with an active temperament and an ingenious brain, possessing no special vocation, but capable of anything that calls for initiative and resolution, full of ideas, with both the will and the knowledge to carry out an enterprise, he inspired confidence in others, found capital as he needed it and started one venture after another, including electrical schemes, the purchase of rivers and waterfalls, the organization of motor services in the colonies, of steamship lines and of mining companies. In a few years he had floated a dozen of such enterprises, all of which succeeded.