and he added: "I don't think that was a real perpetual motion machine. The springs made it work. But, come on, or it will be too late for our motor boat ride."
With a big basket, filled with good things to eat, which the cook obligingly put up for them, the four boys were soon at the dock where Dick's craft was moored.
"Let's go to Handell's Island," proposed Bricktop. "I heard there was a cave there that no one ever got to the end of."
"That'll be fun. We'll explore it," said Dick, always ready for any sort of an adventure.
Heading the boat toward the island, which was about ten miles away, the boys stretched out on the cushions to enjoy the trip. It was a beautiful July day, hot enough to make a ride on the lake the height of enjoyment.
They reached the island in quick time, for the boat was a fast one, but, to their disappointment, the cave did not prove so mysterious as they had hoped. They managed to get to the end of it, though the way was choked with dirt and rocks, and found nothing of interest.
"This cave is a regular lemon," announced Bricktop.
"What did you hope for? To find some of Captain Kidd's treasure?" asked Walter.
"Well, it might have been used by the Indians once," was the red-haired youth's answer. "Some day I'm going to bring a lantern and see
