"Let's get some fresh batteries while we're in town," Rick suggested. "Then we can check these out tonight."
"Okay. And remind me to pick up a new mouthpiece for the lung Jan uses. She says the one that's on it now is too big and uncomfortable. It hurts her mouth."
Jan had become proficient under water with only a few hours practice. Rick had led the girls through the entire series of underwater maneuvers with the lungs, including practice in sharing one lung between them. He was satisfied that they both had a thorough understanding of team swimming and enough sense to stay out of at least the more obvious troubles novices can get into. He was content now to let them go off on their own, which they did fairly often.
After Rick's estimated hour the girls were ready—except that Barby had to make a phone call. She spent another fifteen minutes arranging a small get-together at a friend's home to introduce Jan to her chums.
"Now," she said brightly. "We're ready. Are you?"
Rick wisely refrained from comment.
Ten minutes later the four were in the Brants' car, en route to Barby's destination. Rick dropped the girls off and arranged to pick them up in two hours, then he turned the car toward town.
"Let's visit Duke and Jerry," he suggested.
Scotty looked at him. "Still bothered, aren't you?"
Rick shrugged. It was hard to pinpoint the way he felt. He tried to put it into words. "I've talked to the scientists, including Parnell Winston. None of them has ever heard of an ailment like the thing that struck the team scientists. Winston especially knows a lot, because he's studied the human brain extensively. He doesn't even know of anything similar."