“We’ve never gone as far as Karnac Lake yet,” Lettie pouted. “Always something happens before we get there. If you don’t take us this time, boys, we’ll go over to the enemy in a body!”

“What enemy?” demanded Billy.

“Barrington Spink. He’s always asking us to accompany him on the White Albatross.”

“Why don’t you go with him, then?” snapped Billy. “Nobody’s holding you.”

“Now, children!” admonished the doctor’s daughter. “Don’t quarrel.”

Dan and Mildred only laughed over the bickerings of the other couple. Soon the Speedwells’ boat was made ready and the girls got aboard, while Dan and Billy pushed her out from the landing.

There was no gale blowing, but a good, stiff breeze—and it was fair. The huge sail of the Fly-up-the-Creek filled almost immediately, and they moved steadily out of the cove.

Outside, the White Albatross was maneuvering, Spink evidently waiting as usual to try a brush with the Speedwells’ craft. Barry shot the white iceboat down toward them as they came out of the cove, and shouted:

“Better come aboard here, girls, if you want to reach the lake. I’m on my way!”

“Who’s going to tow you?” demanded Billy.