Larry began to grin long before they reached the spot.
They finally pulled up alongside the object and stopped.
The boys regarded it solemnly, then looked into each other's eyes.

There followed a shout of laughter.
The object that had been discovered by them was a stick, which had been thrust down into the soft bottom in shallow water.

A lantern had been tied to the top of the stick.

It was this lantern, at the end of a stick, that Larry Goheen had been watching all night, believing it to be the anchor light of the "Red Rover." It was plain that the girls had known that they were to be watched, and that they had taken the easiest possible way to outwit their friends, by placing the anchor light on a stick and leaving it at the anchorage while the "Red Rover" slipped away unobserved under cover of the darkness.
"Stung!" groaned Sam.
"Worse than that," answered George.

"There aren't any words in the language to express what we'd like to say.