Each had his ears alert only for the orders of the captain.
Somehow, as the canoe moved out, each one had the same feeling.
The "Scalp-hunter" was not moving quite as it should do.
"There is at least one of you fellows who isn't doing all he should, or just as he should," Dick murmured quietly.

"Which one is it ?" There was no immediate response, though all five of the boys gave renewed attention to their work.

Still, all of them had the same uneasy impression that there "was a screw loose somewhere." "It's just as though we had a drag holding us back," Dick muttered disappointedly.
"Perhaps it's only because we're not quite warmed up yet," Tom hinted.
"No; it isn't that," Prescott responded.

"I wish I knew just what does ail us.

Take the second speed, fellows, and each of you watch his dip and recovery.