Monday was a cold, dreary, disagreeable day. The wind continued northeast; a fine, drizzly rain was falling, and a thick fog had settled over the lake, which effectually concealed the camp of the Rovers from the main shore.

An excursion had been planned for the day by the two boat clubs; but the weather was so unpropitious that it was abandoned. About nine o'clock, however, the members of the clubs began to assemble at their halls in search of such recreation as could be found indoors.

Frank opened the Zephyr's boat-house as usual, and great was his dismay when he discovered that the boat was not in its berth. Calling Uncle Ben from the stable, he announced to him the astounding intelligence that the Zephyr had been stolen!

"What does it mean, Uncle Ben?" he asked, in deep anxiety.

"I can't tell you, Frank; only, as you say, it has been stolen. It couldn't have broken adrift."

"Of course not; and one of the windows is open."

"That accounts for it," replied Uncle Ben, as he walked down the boat-house and looked out upon the lake. "I will take the Sylph and hunt it up."

"Let me go with you, Uncle Ben."

"My eyes! but the Sylph is gone too!" exclaimed the veteran, as he perceived the moorings afloat where she usually lay.

"Strange, isn't it?"

Uncle Ben scratched his head, and did not know what to make of it.

"Here comes Tony, running with all his might," continued Frank. "What's the matter, Tony?"

"Somebody has stolen the Butterfly!" gasped Tony, out of breath."

"And the Zephyr and the Sylph!"

Several of the members of the club now arrived, and the matter was thoroughly discussed.

"Who do you suppose stole them!" said Frank.

"Who? why, Tim Bunker of course," replied Fred.

"But he must have had some help."

"Perhaps not; he has done it to be revenged, because your father turned him out of the club."

"Very likely."

"May be he'll smash them up," suggested William Bright.

"Have you seen anything of Charles this morning?" asked Mr. Hardy, entering the boat-house at this moment.

"No, sir."

"He did not sleep at home last night."

The Zephyrs looked at each other with astonishment, and most of them, probably, connected him with the disappearance of the boats. His intimacy with Tim Bunker created a great many painful misgivings, especially when Mr. Hardy told them that his son had played truant on Saturday; and one of the boys had heard of his being seen with Tim on that day. Various other facts were elicited, which threw additional light upon the loss of the boats. Mr. Hardy was in great distress. It was clear that his son had wandered farther from the path of truth than he had ever suspected.

Frank had gone up to the house to inform his father of the loss of the boats, and Captain Sedley soon joined the party. He sympathized deeply with Mr. Hardy, and was satisfied that his son could not be far off. It was impossible to search the lake, as there were no boats for the purpose.

As nothing could be done at present on the lake, Captain Sedley ordered his horse, with the intention of driving round it in search of the fugitive and of the boats. Mr. Hardy was invited to go with him.

On their arrival at Rippleton they found that Tim Bunker was missing, as well as a great many other boys. They continued to examine the shores of the lake till they reached Joe Braman's house, on the north side.

Captain Sedley inquired for his boat; and Joe, after trying to evade the truth, confessed that he had let it to Tim for a week, but did not know where he had gone with it. They were sure then that the boys were engaged in some mad enterprise: and at about eleven o'clock the two gentlemen reached home, without having obtained any intelligence of Charles.

"Have you discovered anything, Ben?" asked Captain Sedley.

"Yes, sir; I heard voices in the direction of Center Island."

"They are there, then," replied Captain Sedley, as he repaired to the boat-house.

About one o'clock the fog lifted, and revealed to the astonished party the camp of the Rovers. A large fire burned near the two tents, around which the boys were gathered, for the weather was so inclement as to render Tim's enterprise anything but romantic.

The Sylph, the two club boats, and Joe Braman's "gondola" lay near the shore, apparently uninjured.

"This is a mad frolic," said Captain Sedley; "but we may be thankful it is no worse."

"My boy in company with such young scoundrels!" added Mr. Hardy, bitterly.

"He is sick of them and the adventure I will warrant."

"I hope so."

"Charles never did like Tim Bunker," suggested Frank.

"What is to be done?" asked Mr. Hardy.

"We can do nothing; they have all the boats. They have managed well, and we are helpless."

"Can't we build a raft, father?" added Frank.

"If we did, they would take to the boats and keep out of our way. Go to the house, Frank, and bring me the spy-glass. We will examine them a little more closely."

"They'll get enough on't afore to-morrow," said Uncle Ben.

"It will cure them of camping out."

"Tim said, the last time he was with us, that we ought to camp out," added William.

"The best way is to let them have it out till they are sick on't," continued Uncle Ben. "It won't hurt 'em; they won't get the scurvy."

Captain Sedley took the glass on Frank's return, and examined the camp. By its aid he obtained a very correct idea of their encampment. The Rovers were at dinner, and he recognized Charles Hardy and several of his companions. The glass was taken by several of the party; and, after this examination, even Mr. Hardy concluded that it was best to make a............