"I really believe somebody took the ice-boat," remarked Dave. "As the sail was down I don't see how she could budge of herself."

"Exactly my way of thinking," answered Roger. "And I've got an idea who took the craft, too."

"Those Rockville cadets?" queried Henshaw.

"Yes."

"They wouldn't be above such a piece of mischief," said Messmer. "They feel mighty sore over the way we outsailed them that time we raced."

"They'll be likely to sail the boat to our dock and leave her there,"

said Shadow. "Puts me in mind of a story I once heard about----"

"I don't want to listen to any stories just now," grumbled Henshaw. "I want to find that ice-boat. If we can't find her we'll have to walk home."

"What a pity we didn't bring our skates!" cried Dave. "The wind is very light, and if we had them we might catch up with whoever took the craft.

I am by no means certain the Rockville cadets are guilty. When we met them they were going home, and they didn't know we were coming here."

"n.o.body knew that," said Messmer.

"Who was the last person we met on the river before landing?" questioned the senator's son.

All of the boys thought for a minute.

"I saw Link Merwell," said Shadow.

"Yes, and Nat Poole was with him," answered Henshaw. "Merwell has become quite a crony of Nat Poole's since Gus Plum dropped out."

Link Merwell was a new student, who had come to Oak Hall from another boarding school some miles away. He was a tall, slim fellow with a tremendously good opinion of himself, and showed a disposition to "lord it over everybody," as Sam Day had expressed it. He was something of a dude, and it was their mutual regard for dress that caused him and Nat Poole to become intimate.

"Then I believe Poole and Merwell are the guilty parties," declared Dave. "They must have seen us land, and Poole, I know, is itching to pay us back for the way we have cut him."

"All of which doesn't bring back the ice-boat," observed Messmer. "The question is, What are we to do?"

"Hoof it back to Oak Hall--there is nothing else," answered the senator's son, sadly.

Hardly had Roger spoken when Dave heard a peculiar sound on the rocks behind the crowd. He looked back and saw Mike Marcy's mule, nibbling at some bushes.

"The mule--I'm going to catch him!" he e.j.a.c.u.l.a.t.ed, and made a leap for the animal. Just as the mule turned he caught hold of the halter.

"Whoa there! Whoa, you rascal!" he cried, and then, watching his chance, he flung himself across the mule's back. The animal pranced around in a lively fashion.

"Look out, Dave, he'll throw you!"

"He'll kick you to death if he gets a chance!"

"Remember, he's a vicious beast!"

The mule continued to dance about and kicked high in the air, throwing Dave well forward. But the boy who had been brought up on a farm clung on, grasping the mule's ears to steady himself. Then of a sudden the mule turned and dashed away through the bushes.

"He's running away with Dave!"

"Look out for the tree branches!"

Dave paid no attention to the cries. He had all he could do to keep from falling under the animal. Away went boy and mule, over the rough rocks in a fashion which nearly jounced the breath from the rider's body.

Then, just as they came close to some low-hanging trees where Dave felt certain he would be hurt, the mule turned again, leaped for the sh.o.r.e, and sped out on the ice of the river.

"So that's your game!" cried Dave, between his set teeth. "All right; if you want to run you can carry me all the way to Oak Hall!"

Away went the mule, as if accustomed to run over the ice all his life.

He was a sure-footed creature and took only one or two slides, which amounted to nothing. The boys on the sh.o.r.e saw Dave and mule disappear in the darkness and set up a cry of wonder.

"Hi! come back here, Dave!" sang out Roger.

"If you are going to ride to the Hall take us with you!" yelled Shadow.

"He won't stop till he's tired out," said Henshaw. "And goodness only knows where he'll carry Dave."

"Trust Dave to take care of himself," answered the senator's son. "I never saw him get into a hole but that he managed to get out again."

"I hope the mule doesn't land him in some crack in the ice," said Messmer.

On and on through the gathering darkness sped the mule, with Dave clinging to his back with a deathlike grip. The animal was young and full of go and seemed thoroughly to enjoy the run.

"Talk about mules being slow," panted the boy. "The chap who thinks that ought to be on this steed. Why, he'd win on a race-track sure!"

A half-mile was quickly covered, and then the mule neared the bank of the river, where the latter made a long curve. Here there was a fair-sized creek, and up this the animal dashed, in spite of Dave's efforts to stop him or get him to keep to the river proper.

"Whoa, you rascal!" sang out the youth for at least the fiftieth time, and then he caught sight of a white sail just ahead of him. The next moment the mule b.u.mped into the edge of the sail, shied to one side, and sent Dave sprawling on the ice. Then the animal steadied himself and made tracks for the road which led to Mike Marcy's farm. Evidently he was tired of roaming around and of being ridden, and was now going home.

[Ill.u.s.tration: The mule shied to one side and sent Dave sprawling on the ice.--_Page 101._]

Somewhat dazed, Dave picked himself up and gazed at the ice-boat. It was the _s...o...b..rd_, and on it were Nat Poole and Link Merwell.

"Hullo, if it isn't Dave Porter!" muttered Poole, in amazement.

"Where did he get that mule?" questioned Merwell.

"I'm sure I don't know. But this makes a mess of things. I didn't want that crowd to know we had taken the ice-boat," went on the dudish youth.

Dave picked up the cap which had fallen on the ice and ran up to the ice-boat. Those on board had run into the creek by mistake and were trying to turn the _s...o...b..rd_ around.

"What are you doing with that craft?" asked Dave.

"That's our business," retorted Nat Poole.

"I think it is my business. That boat belongs to Messmer and Henshaw."

"We found it, and we are going to have a sail back to Oak Hall," said Link Merwell.