The girls nodded. After making the acquaintance of the young man in the manner related in our first volume, they had learned the queer fact of Mr. Blackford having a sister of whom he had lost track. At one time he hoped it might develop that she was the strange girl who fell out of the tree, but it was not so. This girl, Carrie Norton, had, after spending some time in Deepdale, departed to live with a distant relative. Mr. Blackford had engaged a firm which made a specialty of locating missing persons to look for his sister, but so far there had been no result. "And it doesn't look as though this were going to be very promising," the young man went on. "You know this searching firm has been delving among my wood-pile relations, as I call them, looking for clues," he went on. "They are getting all the old documents, bits of family history, descriptions, and so on, that they can lay hands on. It all helps, in a way, but we haven't had much luck so far. But you may be interested in something that just came up, and you may be able to help me. "I've been traveling about, in connection with my business, and as I knew I would 'make' this town to-night, I had all my mail sent here. Imagine my surprise when I got to my hotel, a little while ago, to find the most promising clue yet." "What is it?" asked Betty, eagerly. "I thought you might be interested," said the young man, "and that is why I called at your house," and he nodded to Will. "You had gone out," remarked Will to Grace, "so I asked dad where, as the maid said you'd all been in the library. Then I called up here," and he nodded to Amy. "Glad you did," she returned. She seemed to have forgotten the trouble of the afternoon. "Well," went on Mr. Blackford, "I feared it was a sort of imposition to come, and----" "I told him it wasn't at all," interrupted Will. "So on I came," proceeded the young business man. "But what is the clue?" asked Grace, interestedly. "This," was the reply, as he took some papers from his pocket. "But it's a clue that----" "Isn't a clue," put in Will. "Because----" "It breaks off in the middle." "Oh, Will, let him tell it; can't you?" demanded Grace, impatiently. "We don't know whom we're listening to." "Well, to be brief," said Mr. Blackford, "the firm I have engaged, the other day, wrote me that they were on the track of my sister. They felt sure they were going to find her, and I was very hopeful. "It seems that they had found some old documents in the attic of a house where some distant relatives live. They wrote me they were sending them on, and--here they are!" He brought out a bundle of time-stained and yellow papers, and spread them on the table. "Gracious!" cried Will. "Your sister must be quite elderly to have such ancient documents refer to her."