"Well, for gracious sake!" was all Sally could reply to this astonishing remark. And a moment later, "How on earth do you know?"

"I don't _know_. I'm only guessing at it," replied Doris. "But I have one or two good reasons for thinking we've been on the wrong track right along. And if I'd known about _her_ before, I'd have thought so long ago."

"But what _is_ it?" cried Sally again, bursting with impatience and curiosity.

"Sally," said Doris soberly, "I'm going to ask you not to make me explain it all just yet. I would if I had it all clear in my mind, but the whole idea is just as hazy as can be at present. And you know a thing is very hard to explain when it's hazy like that. It sounds silly if you put it into words. So won't you just let it be till I get it better thought out?"

"Why, yes, of course," replied Sally with an a.s.sumed heartiness that she was far from feeling. Truth to tell, she was not only badly disappointed but filled with an almost uncontrollable curiosity to know what Doris had discovered about her secret that she herself did not know.

"And I'm going to ask you another thing," went on Doris. "Do you suppose any one around here knows much about the history of Miss Camilla and her family? Would your grandfather be likely to know?"

"Why, yes, I guess so," replied Sally. "If anybody knows I'm sure it would be he, because he's the oldest person around here."

"Then," said Doris, "I want you to let me talk to your grandfather about it. We'll both seem to be talking to him together, but I want to ask him some questions very specially myself. But I don't want him to suspect that we have any special interest in the thing, so you try and make him talk the way you did that night when he told you all about the wrecks, and the _Anne Arundel_. Will you?"

"Oh, yes," agreed Sally. "That's easy. When shall we do it? This afternoon? I think he'll be down at the Landing, and we won't have any trouble getting him to talk to us. There aren't many around the Landing yet, 'cause the season is so early, and I'll steer him over into a corner where we can be by ourselves."

"That's fine!" cried Doris. "I knew you could manage it."

"But tell me--just one thing," begged Sally. "What made you first think that Miss Camilla had anything to do with this? You can tell me just _that_, can't you?"

"It was the little Sevres vase on the mantel," explained Doris, "and the way she spoke of it. I know a little,--just a tiny bit about old china and porcelains, because my grandfather is awfully interested in them and has collected quite a lot. But it was the way she _spoke_ of it that made me think."

Not another word would she say on the subject. And though Sally racked her brains over the matter for the rest of the day, she could find no point where Miss Camilla and her remarks had the slightest bearing on that secret of theirs.

It was about two o'clock that afternoon, and the pavilion at the Landing was almost deserted. Later it would be peopled by a throng, young and old, hiring boats, crabbing from the long dock, drinking soda-water or merely watching the river life, idly. But, during the two or three hot hours directly after noon, it was deserted. On this occasion, however, not for long. Old Captain Carter, corn-cob pipe in mouth, and stumping loudly on his wooden leg, was approaching down the road from the village. At this hour he seldom failed to take his seat in a corner of the pavilion and wait patiently for the afternoon crowd to appear. His main diversion for the day consisted in his chats with the throngs who haunted the Landing.

He had not been settled in his corner three minutes, his wooden leg propped on another chair, when up the wide stairs from the beach appeared his two granddaughters, accompanied by another girl. Truth to tell, they had been waiting below exactly half an hour for this very event. Doris, who had met him before, went over and exchanged the greetings of the day, then casually settled herself in an adjacent chair, fanning herself frantically and exclaiming over the heat. Sally and Genevieve next strolled up and perched on a bench close by. For several minutes the two girls exchanged some rather desultory conversation. Then, what appeared to be a chance remark of Doris's but was in reality carefully planned, drew the old sea-captain into their talk.

"I wonder why some people around here keep a part of their houses nicely fixed and live in that part and let the rest get all run down and go to waste?" she inquired with elaborate indifference. Captain Carter p.r.i.c.ked up his ears.

"_Who_ do that, I'd like to know?" he snorted. "I hain't seen many of 'em!"

"Well, I pa.s.sed a place this morning and it looked that way," Doris went on. "I thought maybe it was customary in these parts."

"Where was it?" demanded the Captain, on the defensive for his native region.

"Way up the river," she answered, indicating the direction of Slipper Point.

"Oh, _that_!" he exclaimed in patent relief. "That's only Miss Roundtree's, and I guess you won't see another like it in a month of Sundays."

"Who is she and why does she do it?" asked Doris with a great (and this time real) show of interest. And thus, finding what his soul delighted in, a willing and interested listener, Captain Carter launched into a history and description of Miss Camilla Roundtree. He had told all that Sally had already imparted, when Doris broke in with some skilfully directed questions.

"How do you suppose she lost all her money?"

"Blest if I know, or any one else!" he grunted. "And what's more, I don't believe _she_ lost it all, either. I think it was her father and her brother before her that did the trick. They were great folks around here,--high and mighty, we called 'em. n.o.body among us down at the village was good enough for 'em. This here Miss Camilla,--her mother died when she was a baby--she used to spend most of her time in New York with a wealthy aunt. Some swell, she was!--used to go with her aunt pretty nigh every year to Europe and we didn't set eyes on her once in a blue moon. Her father and brother had a fine farm and were making money, but she didn't care for this here life.

"Well, one time she come back from Europe and things didn't seem to be going right down here at her place. I don't know what it was, but there were queer things whispered about the two men folks and all the money seemed to be gone suddenly, too. I was away at the time on a three-years' cruise, so I didn't hear nothin' about it till long after.

But they say the brother he disappeared and never came back, and the father died suddenly of apoplexy or something, and Miss Camilla was left to shift for herself, on a farm mortgaged pretty nigh up to the hilt.

"She was a bright woman as ever was made, though, I'll say that for her, and she kept her head in the air and took to teaching school. She taught right good, too, for a number of years and got the mortgages off the farm. And then, all of a sudden, she began to get deaf-like, and couldn't go on teaching. Then she took to selling off a lot of their land lying round, and got through somehow on that, for a while. But times got harder and living higher priced, and finally she had to give up trying to keep the whole thing decent and just scrooged herself into those little quarters in the 'L.' She's made a good fight, but she never would come down off her high horse or ask for any help or let any one into what happened to her folks."

"How long ago was all that?" asked Doris.

"Oh, about forty or fifty years, I should think," he replied, after a moment's thought. "Yes, fifty or more, at the least."

"You say they owned a lot of land around their farm?" interrogated Doris, casually.

"Surest thing! One time old Caleb Roundtree owned pretty nigh the whole side of the river up that way, but he'd sold off a lot of it himself before he died. She owned a good patch for a while, though, several hundred acres, I guess. But she hain't got nothin' but what lies right around the house, now."

"Didn't you ever hear what happened to the brother?" demanded Doris.

"Never a thing. He dropped out of life here as neatly and completely as if he'd suddenly been dropped into the sea. And by the time I'd got back from my voyage the nine-days' wonder about it all was over, and I never could find out any more on the subject. Never was particularly interested to, either. Miss Camilla hain't nothin' to me. She's always kept to herself and so most folks have almost forgotten who she is."

As the Captain had evidently reached the end of his information on the subject, Doris rose to take her leave and Sally followed her eagerly.

"Well, did you find out what you wanted?" she cried, as soon as they were once more out on the river in old "45."

"I found out enough," answered Doris very seriously, "to make me feel pretty sure I'm right. Of course, I can only guess at lots of it, but _one_ thing I'm certain of: that cave had nothing to do with smugglers or pirates--or anything of that sort!"

Sally dropped her oars with a smothered cry of utmost disappointment.

"I can't believe it!" she cried. "I just can't. I've counted on it _so_ long--finding treasure or something like that, I mean. I just can't believe it isn't so."

"It may be something far more interesting," Doris replied soothingly.

"But there's just one trouble about it. If it's what I think it is, and concerns Miss Camilla, I've begun to feel that we haven't any business meddling with it now. We oughtn't even to go into it."

Sally uttered a moan of absolute despair. "I thought it would be that way," she muttered, half to herself, "if I shared the secret. I _knew_ they'd take it away from me!" She shipped her oars and buried her face in her hands. After a moment she raised her head defiantly. "Why, I don't even know why you say so. You haven't told me yet a single thing of what it's all about. Why _should_ I stay away from that place?"

"Listen, Sally," said Doris, also shipping her oars and laying an appealing hand on her arm, "I ought to tell you now, and I will. Perhaps you won't feel the same about it as I do. We can talk that over afterward. But don't feel so badly about it. Just hear what I have to say first.

"I think there has been some trouble in Miss Camilla's life,--something she couldn't tell any one about, and probably connected with that cave.

What your grandfather said about her father and brother makes me all the more sure of it. I believe one or the other of them did something wrong,--something connected with money, perhaps, embezzled it or forged checks or something of that kind. And perhaps whoever it was had to hide away and be kept so for a long time, and so that cave was made and he hid there. Don't you remember, your grandfather said the brother disappeared suddenly and never came back? It must have been he, then.

And perhaps Miss Camilla had to sell most of her valuable things and make up what he had done. That would explain her having parted with all her lovely porcelains and china. And if so much of the land around the house once belonged to her, probably that part where the cave is did too."

"But what about that bit of paper, then?" demanded Sally, who had been drinking in this explanation eagerly. "I don't see what that would have to do with it."

"Well, I don't either," confessed Doris. "Perhaps it _is_ the plan of the place where something is hidden, but I'm somehow beginning to think it isn't. I'll have to think that over later.

"But now, can't you see that if what I've said is right, it wouldn't be the thing for us to do any more prying into poor Miss Camilla's secret?

It would really be a dreadful thing, especially if she ever suspected that we knew. She probably doesn't dream that another soul in the world knows of it at all."

Sally was decidedly impressed with this explanation and argument, but she had one more plea to put forward.

"What you say sounds very true, Doris, and I've almost got to believe it, whether I want to or not. But I'm going to ask just one thing. Let's give our other idea just a trial, anyway. Let's go there once more and see if that scheme about the floor and the place in the corner is any good. It _might_ be, you know. It sounded awfully good to me. And it won't hurt a thing for us to try it out. If we don't find anything, we'll know there's nothing in it. And if we do find anything that concerns Miss Camilla, we'll let it alone and never go near the place again. What do you say?"