"I'll have the auto around in a jiffy!" he exclaimed. "Lucky it's summer, and you'll not take cold. Just rest yourself, Fenn, until I come back, and we'll have you all right again."

"But how in the world did you ever get into the lake?" asked Ruth, as her father hurried away.

"I jumped in."

"Jumped in!" repeated Bart. "How was that?"

"Now we mustn't ask him too many questions," interrupted Ruth. "He's not able to answer."

"Oh yes I am," replied the lad who had been through rather strenuous times in the last few hours. Thereupon he briefly related what had happened since his chums left him to go hunting, ending up with his unexpected plunge into the lake. In turn Bart told how they had searched for him, and how, having met Mr. Hayward and his daughter, the hunt was brought to such a timely ending.

"But what were those men taking out of the cave?" asked Frank, when Ruth had gone down the sh.o.r.e, along which a road ran, to see if her father was returning.

"That's what we've got to discover," answered Fenn. "I think there's a valuable secret back of it. We'll go--"

But further conversation was interrupted by the arrival of the auto--the same big touring car that had so nearly come to grief in Darewell. The four boys got in, Fenn was wrapped in a lap robe, to prevent getting chilled on the quick ride that was to follow, and the car was sent whizzing along an unfrequented road to Mr. Hayward's home, several miles away.

The three chums wanted to ask Fenn all sorts of questions about his experiences, but Ruth, who const.i.tuted herself a sort of emergency nurse, forbade them.

"You'll have time enough after he has had a rest," she said. "Besides, he's just gotten over a fever, you say. Do you want him to get another?

It looks as though he was."

And that was just what happened. When the auto reached Mr. Hayward's home Fenn was found to be in considerable distress. His cheeks were hot and flushed and he was put to bed at once, though he insisted, with his usual disregard of trifles that concerned himself, that he was "all right."

A physician was summoned, and prescribed quiet, and some soothing medicine.

"He has had a severe shock," he said, "and this, on top of his former attack of fever, from which he had barely recovered, has caused a slight relapse. It is nothing dangerous, and, with careful nursing he will be all right in a few days."

"Then, I'm going to take care of him," declared Ruth. "It will be a chance to pay back some of his, and his folks' kindness to me and my father. Now mind, I don't want you boys to speak to Fenn unless I give you permission," and she laughed as she shook her finger at the chums to impress this on them.

Fenn, under the influence of the medicine, soon fell into a deep sleep, which, the pretty nurse said, was the best thing in the world for him.

"I guess we'd better go back to camp," proposed Bart. "All we brought away from there are the guns, and some one might come along and steal the other stuff, which isn't ours."

"That's so, those smugglers are still around I suppose," added Ned. "We had better get back, I think."

"You'll do nothing of the sort," declared Mr. Hayward good-naturedly.

"You're going to be my guests, or I'll be very much offended. We've not got such a fine place as some, but you're welcome to what there is. If things were different--but there, I want you to stay."

He seemed affected by something, and his manner was so queer that the boys could not help noticing it. Ruth, too, appeared embarra.s.sed, and, at first, Bart and his chums thought it might be that she was not prepared for company, since, as her mother was dead, she had the whole care of the house, though there was a servant to help her. But her invitation, which she added to that of her father's, a.s.sured the boys that they would be very welcome.

"You can't rough it so much as you could out in the woods," said Ruth, "but I think you'll like it here. We have a motor boat, and you may wish to run it on the lake."

"A motor boat!" exclaimed Bart. "That settles it! We stay!"

"But what about our camp stuff?" asked Frank.

"I'll send a man to gather it up and ship it back to Duluth," said Mr.

Hayward. "There's no need of you going back there at all. I'll be glad to have you stay. We're a little upset on account of--"

He stopped suddenly, and glanced at his daughter, who did not appear to be listening to what he was saying. But she heard, nevertheless, as was shown by her next remark.

"Oh, dad means some of the servants have gone," quickly explained Ruth.

"You see we had too many," she went on. "I decided we could get along with one, for I want to help do the work. I must learn to be a housekeeper, you know," and she blushed a little. "We're not upset a bit, daddy. You see, I'll manage."

It seemed as though something sad was worrying Mr. Hayward, but, he soon recovered his usual spirits, and got the boys to give him directions for shipping back their camp stuff.

"Now, I'll look after it," he said, as he prepared to leave the house, having changed his wet garments for dry ones. "I have some other matters to attend to, and I may not be back until late. I guess you can get along here. You can pretend you're camping out, and, if you get tired of that, Ruth will show you where the motor boat is. Only, don't upset,"

and, with that caution, he left them.

The three chums decided they would try the boat at once, and, Ruth, having ascertained that they knew how to run one, showed them where the launch was kept in a neat boat-house on the sh.o.r.e of Lake Superior.

"Don't be gone too long," she said. "You can't tell what will happen to Fenn."

"I guess he couldn't be in better hands," said Frank, with a bow.

"Oh, thank you!" exclaimed Ruth, with a pretty blush.

"That'll do you," observed Bart, nudging Frank with his elbow. "I'll tell Fenn when he gets well."

Ruth returned to her patient, after urging the three chums to be back in time for dinner. She found Fenn awake, and with unnaturally bright eyes.

"You must go to sleep," she told him.

"I can't sleep."

"Why not?"

"I'm thinking of something."

"What about?" she asked with a little laugh. "About all the wonderful adventures you had?"

"Partly, and about that cave. It's the same one."

"The same one? What do you mean?"

"The same one you talked about when you were at our house. The mysterious cave, where the men were at work. I see it all now. It's the same cave!

There is some secret about it! Tell me what it is. Don't you remember what you said? You wanted to find the cave, but couldn't. I have found it!"

"Oh!" exclaimed Ruth. She drew back as if frightened. "Oh!" she cried again. "Can it be possible. It seems like a dream! Can it be my cave?"

"Tell me about it," suggested Fenn, for even his illness could not deter him from trying to solve the mystery.

"I am going to tell you a secret," answered Ruth. "It is something I have told no one. You know my father is--or, rather he was--quite wealthy. He owned considerable property, and was counted a millionaire.

But lately, through some misfortune, he has lost nearly all his wealth.

I suspect, though I do not know for sure, that some wicked men have cheated him out of it. But he does not know that I am aware of his loss.

He has kept it a secret and he tries to keep up when he is with me, but I can see the strain he is under. He does not want me to suffer, dear daddy! But I don't mind. I don't care for money as long as I have him.

"He thinks he can get his wealth back again, and so he has been making all sorts of sacrifices in order that I may continue to live here, in the same style we used to. But I found out about it. I discharged all the servants but one, to save money, and I am economizing in other ways."