The boys, and in fact the entire scientific staff of Spindrift Island, had been in a state of excitement for the past few days because of a telegram received from Dr. John Gordon. Dr. Gordon had been on leave for some time, working on a special project at a rocket experimental station in the West. A few days before, Dr. Hartson Brant, Rick's father and head of the Spindrift Scientific Foundation, a world-famous research organization, had received word from Gordon that Rick and Scotty were needed for a special assignment. Gordon had not given any details in his wire.
This morning Dr. Gordon had phoned that he had been delayed, but would arrive by Navy plane around noontime. Long before noon, Rick and Scotty had moved Rick's four-passenger Sky Wagon off the grassy runway that ran along the seaward side of the island, then settled down to the rock-throwing session.
Barby said, "I'm pretty good with a slingshot. Let me try."
Scotty handed her the sling. She looked at it dubiously. "What's this? It isn't a slingshot."
"It's a sling," Rick explained. "Not a slingshot. You know—like David and Goliath."
Barby looked her disbelief. "You mean David killed Goliath with two pieces of string and a piece of canvas?"
"He probably used leather thongs and a leather pouch," Scotty said, "but the idea is the same."
"Show her," Rick suggested.
Scotty picked up another of the larger stones and let fly. It dropped short of the earlier throw, but the effect was enough to make Barby's blue eyes open wide.
"Where did you get it?" she asked excitedly.