He looked it over. He knew vaguely that Alua was an island somewhere near Bohol.
"Naturally a fish-driving paddle is used to drive fish," she said. "To—herd them, you might say. People go out in shallow water and form a line. Then they whack paddles like these on the surface of the water. Fish try to get away from the sound and the people herd them where they want them—into fish-traps, usually. I've tried this, while wearing a bathing suit. It makes your skin tingle—smart, rather. It's a sort of pins-and-needles sensation. Fish would swim away from an underwater noise like that!"
Terry examined the carving.
"Well?"
"Of course we think there's something special about the noise these paddles make. Maybe a special wave-form?"
"Possibly," he admitted. "But—"
"We want something else to do the same trick on a bigger scale. Directional, if possible. Not a paddle, of course. Better. Bigger. Stronger. Continuous. We want to drive fish and this paddle's limited in its effect."
"Why drive fish?" asked Terry.
"Why not?" asked the girl. She watched his face.
He frowned a little, considering the problem the girl posed.