"Sorry you are laid by, old man," Max said cheerfully as he was shown into Win's room. "Better luck soon."

"It's good of you to come," replied Win, grasping the hand so cordially offered and relieved to see that the pleasant young face bore no expression of the sympathetic pity Win so often read in older countenances.

"Well, my being here is as much of a surprise to me as to any one," said Max, sitting down by the bed. "On Friday I expected to spend my Sunday in Paris. But it chanced that I successfully engineered a rather ticklish job for the Embassy, and the Chief was pleased. As a figurative pat upon the head he gave me the week-end off. You should have seen the way my car went to Granville! Jean drove till we were clear of Paris and then I took the wheel and things began to hum. From the tail of my eye I could see Jean devoutly crossing himself whenever we hit the earth, but we made the boat and didn't so much as run down a hen. I did wonder that we weren't held up anywhere for exceeding the speed limit, but the mystery was explained when we reached the Granville pier."

Max stopped with a mischievous laugh. "The Embassy has several official machines," he explained, "and of course they are so marked they are easily recognizable. I always use my own car, and am authorized to sport the Embassy insignia when on official business. I forgot to remove it before starting and that was why not a single gendarme did more than salute as we tore past. Good joke, so long as it ended well, but if we'd come a cropper on the way, there'd have been rather a row and Max would have stood for an official wigging, to say the least. Lucky for us that nothing went wrong. What's done you up, old fellow?"

Win looked at him wistfully. "Just exploring the Manor cave," he said with a sigh. "I did so want to see it, and I made Roger take me. I managed to get down all right, but it took over an hour to climb the cliff. The kid is wild because he thinks he's half-killed me."

"Oh, say, that's a shame," said Max. "I wish I'd known that you wanted to go. Pierre and I could have rigged a rope somehow and helped you get back."

Win's face just then was pitiful. Max's eyes grew very gentle but he did not utter one word of sympathy. "I've been led a lively pace since I reached the Manor," he went on. "Between Connie's ghost hunt and the extraordinary church she chose to attend this morning and your discovery in the library, my existence hasn't lacked variety. Gay Paris is quiet beside this! But there's nothing in the world I'm so keen on as hidden treasure. I'm pretty sure I have a special talent for hunting it down. To be sure the only time I ever tried, I made a giddy ass of myself and got into a jolly mess, but I wonder will I succeed with this. Connie thinks you've the tail of an idea. Can't you put me on?"

"That was what I wanted to see you for," replied Win, his self-possession quite restored. "Please open the lower drawer of that desk. Right on top is a roll of tracing paper."

"Why, this is a copy of the Manor plans," said Max, as he spread out the thin sheet.

"Yes," said Win. "Colonel Lisle let me trace them. Tell me, does anything about them strike you as odd?"

Max considered the plan carefully. "I can't say it does," he admitted after a minute survey. "Give me a lead."

"That dotted line," said Win, pointing to it with Max's pencil, "according to Colonel Lisle, marks the path down to the cottages on the shore, only the path curves more now than it did when the plan was first made. Don't you think it strange that it was the only path put on the plans? Even the state driveway isn't indicated."

"That, I suppose, wasn't made then."

"But surely," persisted Win, "there was some driveway to the main road. Why should this especial path be marked? It couldn't have been the most important, even at that time."

"That does seem true," replied Max thoughtfully.

[Illustration: WIN'S PLAN OF THE MANOR CELLARS.]

"Now look at the point where the dotted line comes to the house," Win went on, tracing its course as he spoke. "This is the very oldest vault of all, under the library, you know. On the plan, its northern wall is continued flush by the northern side of the addition made later, and this dotted line runs parallel to it, but—it runs inside the foundations."

"So it does," Max agreed. "But isn't that due to clumsy drawing? There's an axiom, you know, about it being impossible for two bodies to occupy the same space. Two lines couldn't occupy the same location on a plan."

"Yes," said Win, "but if this is a path, what is it doing inside the house?"

There followed a second of silence and then Max gave a low whistle.
"I'm on," he announced. "Clever reasoning, Win."

"There's another thing, too," said Win, lying flushed and pleased against his pillows. "I spent a lot of time on that dividing partition wall. I'm sure there is no space in it unless it is so thick that even a hollow place wouldn't sound any different. But after I looked again at the plans, I saw that what I should have put my time on wasn't that wall at all, but the northern one, indicated here as parallel to the dotted line. Mr. Max, I'm quite certain that the old original cellar extends farther to the north than this newer part. I mean that the north wall of the new cellar isn't on a line with the old one, not in reality, though here it is intended to look so."

"You mean," said Max, bringing intelligent brows to bear on this explanation, "that this was an underground passage rather than a surface path and that its northern side is the one flush with the original cellar?"

"That's exactly it," said Win. "I think there is a passage running along outside that northern wall down to the cave and the beach. There seems a space on the plan that isn't accounted for in any other way, and that explains why this dotted line runs inside the foundations."

"But, old chap," said Max kindly, "I know that cave from top to bottom.
Truly there is no exit. I've spent hours in exploring the place."

"But when I was on the ledge at the back, there was a draught of fresh warm air from somewhere," Win pleaded. "And Roger said he noticed it when you took him there. Behind the ledge is a big pile of stones and rubble. Couldn't that air get in somehow?"

"It must, since you felt it," agreed Max sensibly. "If I can possibly manage it, I'll make an investigation. But I am booked to sail on Tuesday morning. It may have to stand over until the Easter holidays. I will take a squint at the cellar though this very evening. Did you sound that north wall?"

"No, I didn't," Win admitted. "I spent all my time on the west one. Not until I studied the plans again, did it fully dawn on me that perhaps that line was a passage instead of a path. If that is true, it is the other wall that will bear investigation."

Max still surveyed the plans, his fine young face intent on this problem. He glanced up to meet a very wistful look from Win.

"On the whole, let's wait until Easter," he suggested. "Then you'll be feeling more fit and can come down in the vaults with me."

"I wish you'd inspect that wall," Win replied. "If you find it does sound hollow, will Colonel Lisle let us punch a hole?"

"Sure," said Max encouragingly. "I know jolly well he will. Uncle Dick will be game for any investigation. Only he'll have to be convinced that I'm not pulling his leg. If that north wall resounds like a tomb, I'll tow Uncle down to hark for himself. Why, man, we're getting on swimmingly! That was a mighty clever idea of yours about the dotted line. Connie'll be keen on it too, and anyway she owes me one after getting me into such a beastly mess as she did to-day. I didn't even use unkind language about it either. If the sea is decent tomorrow, I'll trot her down to the cave to see where your fresh air comes from."

"Perhaps it can be felt only when the wind is from a certain direction," observed Win.

"That's more than likely. Yesterday it was south, wasn't it? Very probably it takes a south wind to strike in there. I'm afraid we can't hope for that to-morrow because there seems a storm brewing, on purpose probably to give me a rough trip on Tuesday."

"Weren't you glad of the chance to come?" asked Win.

"I was," said Max expressively, "not only because I always like to get back to the Manor, but because I was pleased with myself to think I'd scored with this especial bit of work, a job of smoothing down an elderly ass who was inclined to be a trifle footy. You see when I decided to go in for the diplomatic service, Dad told me that he would use his influence only to get me an appointment, a try-out. After that it was up to me; if I received promotion it would be because I earned it, not because I was his son. He makes me an allowance because one really couldn't manage on the salary of an attachÉ, but so far as my profession goes, I stand absolutely on my own merits. So Max is feeling proud of himself just now!" he added whimsically. "So's my Dad, if my telegram reached him."

"He must be proud of you," said Win rather soberly. "I so much hope that Roger will condescend to go to Annapolis. You see I can't, and Dad would like one of us in the navy."

"Roger will wake up to a sense of his privileges some day," said Max. "Do you know, Win, some of the finest work in the world has been done by the fellows who were handicapped. Prescott, for instance, writing all his histories, blind in one eye and sometimes half crazed by pain; Milton, too, dictating to his daughters, and Scott, producing so much when he was old and burdened with grief and trouble. And Stevenson, who was ill half his life."

"But they were geniuses," said Win.

"They were also too courageous in spirit to yield to circumstances. To come down to more ordinary people, I think Uncle Dick is mighty fine. He is crippled, useless for the work he expected to grow old in; he saw his only son die for England. You have seen enough of him to know what he is and what he means not only to Laurel Manor but to the Island. I respect and admire him tremendously and I shall owe much of whatever success I score, to him as well as to Dad. There are careers open to you, Win. You are clever and have a fine mind. Roger defers to your opinion. Through your influence, he may accomplish far more than he might alone."

"I don't amount to very much with Roger. Still, I did make him square things with Fisher that day he played truant and went off with you," admitted Win with the ghost of a smile. "Mother only lectured him for bunking, but I persuaded him to apologize and to put in the next Wednesday doing the work he skipped."

"Good for you!" said Max cordially. His gray eyes were very kind and friendly as he rose to leave.

"I hope you'll feel more fit to-morrow," he said, shaking hands. "If I possibly can, I'll run in and make a report; if not, I'll drop a line when I get home to the lurid lights of Paris."

"Shall you drive back with the Embassy insignia on your car?" inquired Win smiling. He looked much brighter and happier than before his visitor came.

Max laughed. "I fancy not," he said as he gathered hat, gloves and riding-crop. "I'm rather anxious to be on my good behavior. No, I'll let Jean drive which will be prudently slow, and I'll meditate about your hidden chest and the dotted path and other things back at the Manor."

"I believe Mr. Hamilton did you more good than the doctor," declared Mrs. Thayne, entering Win's room after his caller had mounted Saracen and ridden away. "You look fifty per cent brighter."

"He's a crackerjack," said Win briefly. "He's promised to do some investigating on his own account and I feel sure that he can induce Colonel Lisle to let us try an experiment if it is needed. But, Mother, there's something I've been meaning to tell you all day, not about the Spanish chest or anything to do with it. You know we spoke once of how Miss Estelle reminded us of some one at home. This morning instead of sending a servant with my breakfast, she brought it herself, and when she was arranging things, I remembered whom it is she looks like. It is your friend, Mrs. Aldrich."

"Win, you're right," said Mrs. Thayne suddenly. "Estelle is like Carrie Aldrich, and not in looks alone, but in manner. Now how can that possibly be? Of course it is only a chance resemblance but it must exist since you notice it, too. I wonder whether Fran ever carried out her intention of asking Edith whether they had any relatives in the United States. She spoke of doing so."

"What good would that do, if Mrs. Aldrich is the person Estelle resembles?" asked Win. "Haven't you known her all her life?"

"I met her at school," replied his mother, "when we both were young girls and then knew her intimately. Of later years, we have seen less of each other, though we have always kept up the friendship. There seems no possible connection between Carrie Aldrich and Estelle and the likeness must be only in our minds. They say, you know, that every person in the world has a double somewhere."

"I'd like mighty well to be Mr. Max's double if I could only choose," muttered Win to himself.