"There is nothing more need be explained just now," interrupted the other woman imperiously; "when you return with the box, you shall know all. What I am requesting you to do can harm no one, but can benefit someone." "Yourself?" "No! That is, in a way, perhaps. But you can judge for yourself when I am able to tell you my reason. That will be when you return. If five pounds is not sufficient, I can give you ten, although I can ill afford it." "I am satisfied with five," said Patricia quickly, and flushing again, for even in her poverty she shrank from taking money. "I don't like mysteries, and only accept your offer as I need money very badly. But for all the wealth in the world I would not go if I thought that there was anything wrong," and she looked searchingly at her companion. "How many times do you need me to assure you that there is nothing wrong," said Mrs. Pentreddle, impatiently; "you are singularly suspicious for a girl of your years. All that is necessary is for you to receive this tiny box from the man who will hand it to you." "How shall I know the man?" "There is no need for you to know him at all. The red light of the lantern will assure him that you are the person who is to receive the box. Well?" Miss Carrol rose nervously and ran her fingers through her hair, as she walked up and down the long room. Her instinct told her to refuse a mission about which she knew so little, but the prospect of earning five pounds in this easy manner was so alluring, that she could not find it in her heart to decline. After all, Mrs. Pentreddle was the sister of the woman who had been, and was, so kind to her, and in every way appeared to be an almost aggressively respectable person. It was worth risking, she thought, and at this moment, as though to clinch the matter, Mrs. Pentreddle's voice broke in on her uneasy meditations. "I can't wait much longer," said the old woman; "if you won't do what I ask, perhaps you will telephone to the nearest office, asking that a messenger-boy may be sent to get what I want. It will certainly be cheaper." This proposal banished Patricia's last scruple, as, if a messenger-boy could be employed, the errand, mysterious as it seemed, could not have anything to do with criminal matters. Miss Carrol picked up the lantern, with its faked red glass. "I shall go at once," she declared hurriedly, for now she feared lest she should lose the money, "but who will attend to your foot while I am away, Mrs. Pentreddle?" "I can stay here, as I am doing. Rest is the sole thing which can cure my sprain. You will only be away an hour, more or less. It is a quarter past eight now, and the distance to the Serpentine bridge is not far. Nine o'clock is the hour. You know exactly what you have to do," and she repeated her instructions, to which the girl listened carefully.