"All right, sit there, if you want," said Meredith, starting off, followed by the other two boys.

Dot watched them for a while, but feeling too uncomfortably cold she slowly skated back to the raft and crouched near the fire.

Mike heard her telling Lavinia what the boys were going to do, and he jumped up, grabbed the end of the birch tree and ran swiftly across the ice with his sure-footed buck-skins helping him.

"Hi! Hi!" cried Mike, trying to get the boys' attention. But the wind was against him.

"Him channel! Big hole! Water swish!" yelled Mike, in an agony of fear lest the boys reach the channel-mark before he could get there.

Paul and Meredith were swift skaters and soon outstripped Don, but just as they came near the log which was the goal, Paul's skate loosened and he fell down on the ice. Meredith came over to assist him, and they found that a screw was loose.

"Don's got a broken knife blade that we can use for a screw-driver. We'll wait for him," said Meredith.

Don soon skated up and produced the knife with the broken blade, and Paul tried to fasten the screw in place again.

So intent were they over the repairing of the skate that neither of them heard an ominous crack along the ice as soon as Don's extra weight came near the log.

A few more dull cracks sounded as the ice seemed suddenly to become lined with crooked white lines. Before Paul could fasten his skate on again, however, Mike's voice reached them.