"Yes," she agreed, "I do believe you're right, Sally. And now that I look it over, these letters and numbers might easily be the key to it all, if we can only work it out. Oh, I never heard of anything so wonderful happening to two girls like ourselves before! Thank you, a million times, Sally, for sharing this perfectly marvelous secret with me." "I do believe I'm enjoying it a great deal better myself, now that I've told you," answered Sally. "I didn't think it could be so before I did. And if we ever discover what it all means--" "Why, precious!" interrupted Doris, turning to Genevieve, who all unnoticed had come to lean disconsolately against the side of the boat, her thumb tucked pathetically in her mouth, her eyes half tearful. "What's the matter?" "I'm hung'y and s'eepy!" moaned Genevieve. With a guilty start, Doris gazed at her wrist watch. It was nearly one o'clock. "Merciful goodness! Mother will be frantic!" she exclaimed. "It's lunch-time now, and we're way up here. And just see the way I look!" She was indeed a scratched, grimy and tattered object. "Whatever will I tell her?" They scrambled to their oars and were out in the river before Sally answered this question. "Can't you tell her you were exploring up on Slipper Point?" "Yes," agreed Doris. "That is the real truth. And she never minds if I get mussed and dirty, as long as I've enjoyed myself in some way that's all right. But I hope I haven't worried her by being so late." They rowed on in mad, breathless haste, passed the wagon-bridge, and came at last in sight of the hotel. But as they beached the boat, and Doris scrambled out, she said in parting: "I've been thinking, all the way down, about that secret map, or whatever it is, and I have a new idea about it. I'll tell you tomorrow morning. This afternoon I've promised to go for a drive with Mother." CHAPTER VI WORKING AT THE RIDDLE But Doris did not have an opportunity to communicate her idea on the following morning, nor for several days after that. A violent three or four days' northeaster had set in, and for forty-eight hours after their expedition to Slipper Point, the river was swept by terrific gales and downpouring sheets of rain. Doris called up Sally by telephone from the hotel, on the second day, for she knew that Sally would very likely be at the Landing, where there was a telephone connection. "Can't you get well wrapped up and come up here to see me a while?" she begged. "I'd go to you, but Mother won't let me stir out in this awful downpour." "I could, I s'pose, but, honestly, I'd rather not," replied Sally, doubtfully. "I don't much like to come up to the hotel. I guess you know why." Doris did know. "But you can come up to my room, and we'll be alone there," she suggested. "I've so much I want to talk to you about. I've thought of something else,--a dandy scheme." The plan sorely tempted Sally, but a new thought caused her to refuse once more.